Publication 52 - Hazardous, Restricted, and Perishable Mail

Summary of Changes

Publication 52, Hazardous, Restricted, and Perishable Mail

Effective September 7, 2023, Publication 52, Hazardous, Restricted, and Perishable Mail, has been updated

with the following changes:

The chapter,

subchapter,

part, appendix,

or section…

titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

Chapter 2, General Guidelines

214 Appeals Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

221.2 Ancillary Endorsements Revised to delete references to First-

Class Mail, Parcel Select Ground,

and USPS Retail Ground.

22632 9-7-23

228 Shipping Papers Revised to delete references to First-

Class Mail and First-Class Package

Service.

22632 9-7-23

23 Handling Hazardous

Materials

Revised to include information on

procedures for handling nonmailable

hazardous materials found in the

mailstream.

22632 9-7-23

Chapter 3, Hazardous Materials

323 Mailer Responsibility Revised to incorporate new

requirements, which became

effective July 9, 2023, for mailers to

use unique Service Type Codes and

Extra Service Codes for package

shipments containing hazardous

material or dangerous goods.

22632 9-7-23

325 DOT Hazardous Materials

Warning Labels and

Markings

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

327 Transportation

Requirements

Revised to delete references to First-

Class Mail, Parcel Select Ground,

and USPS Retail Ground, and to

replace references to First-Class

Package Service with references to

USPS Ground Advantage.

22632 9-7-23

336 USPS Limited Quantity

Surface Materials

Revised to delete a reference to

First-Class Package Service and to

reformat the text to improve

comprehension and readability.

22632 9-7-23

338 Small Quantity Added as new 338, including text

containing small-quantity provisions.

22632 9-7-23

339 Packaging Requirements

for Hazardous Materials

Renumbered from 338, with

quotation marks added before and

after “PG II” in 339.1, “DOT Packing

Groups.”

22632 9-7-23

341.2 Mailability, Packaging,

and Marking

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

341.22 Mailable Explosives Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

342.2 Mailability Revised to add section and title

“342.21 General” above the text

immediately under 342.2 and

renumber 342.21 and 342.22 as

342.22 and 342.23. Also revised to

reflect a title change to director for

the Postal Service Product

Classification and the Pricing and

Classification Service Center (PCSC)

manager.

22632 9-7-23

343.25 Lighters Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

343.27 Authorization to Mail

Ethanol-Based

Flammable Liquids or

Solids

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager, and to

delete references to First-Class Mail

and First-Class Package Service.

22632 9-7-23

346.212 Division 6.2, Infectious

Substances

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager, and to

replace references to products in

item b. with references to USPS

Packaging Instructions.

22632 9-7-23

346.321 Category B Infectious

Substances

Revised to delete a reference to

First-Class Mail.

22632 9-7-23

The chapter,

subchapter,

part, appendix,

or section… titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

346.322 Sharps Waste and Other

Mailable Regulated

Medical Waste

Revised to replace a reference to

merchandise returns service with a

reference to USPS Returns; to delete

a reference to First-Class Mail; and

to reflect a title change to director for

the Postal Service Product

Classification and the Pricing and

Classification Service Center (PCSC)

manager.

22632 9-7-23

346.323 Used Health Care

Products

Revised to delete a reference to

First-Class Mail.

22632 9-7-23

346.324 Forensic Material in

Category B

Revised to delete a reference to

First-Class Mail.

22632 9-7-23

346.325 Nonregulated Materials Revised to delete references to

Postal Service products via which

nonregulated materials are or were

mailable.

22632 9-7-23

346.326 Exempt Human or Animal

Specimens

Revised to delete references to

Postal Service products via which

exempt human or animal specimens

are or were mailable.

22632 9-7-23

Chapter 4, Restricted Matter

434 Replica or Inert Explosive

Devices

Revised to delete references to

Postal Service products via which

registered mail is or was available.

22632 9-7-23

453.36 Return of Prescription

Drugs

Revised to replace references to

merchandise returns service with

references to USPS Returns, and to

delete a reference to First-Class Mail.

22632 9-7-23

453.7 Mail-back Programs Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager, and to

delete a reference to First-Class

Return Package Service.

22632 9-7-23

Chapter 5, Perishable Matter

Exhibit 526.6 Requirements for Mailing

Small, Harmless, Cold-

Blooded Animals (Except

Snakes, Turtles, and

Turtle Eggs)

Revised to clarify that water is

allowed when mailing fish.

22632 9-7-23

Chapter 6, International Mail

621.5 Extra Service Codes and

Shipping Service Files

Added to incorporate new

requirements, which became

effective July 9, 2023, for mailers to

use unique Service Type Codes and

Extra Service Codes for package

shipments containing hazardous

material or dangerous goods.

22632 9-7-23

The chapter,

subchapter,

part, appendix,

or section… titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

622.2 Biological Substances,

Division 6.2

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Chapter 7, Air Transportation Requirements

71 General Revised to delete a reference to

First-Class Mail, and to replace a

reference to First-Class Package

Service with a reference to First-

Class Package International Service.

22632 9-7-23

72 Hazardous Materials: Air

Transportation

Revised to delete a reference to

First-Class Mail, and to replace a

reference to First-Class Package

Service with a reference to First-

Class Package International Service.

22632 9-7-23

726.1 Acceptance Personnel Revised to delete references to First-

Class Mail and First-Class Package

Service and to add a reference to

First-Class Package International

Service.

22632 9-7-23

Appendix C, USPS Packaging Instructions for Mailable Hazardous Materials

USPS

Packaging

Instructions 1A:

Toy Propellant

Devices

Required Authorization Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Documentation Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

USPS

Packaging

Instructions 1B:

Safety Fuse

Required Authorization Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Documentation Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

The chapter,

subchapter,

part, appendix,

or section… titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

USPS

Packaging

Instructions 3C:

Flammable

Liquid or Gas

Lighters

Required Authorization Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Marking Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

USPS

Packaging

Instructions 3D:

Ethanol-based

Flammable

Liquids and

Solids

Ethanol-based Flammable

Liquids and Solids

Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

USPS

Packaging

Instruction 6C:

Category B

Infectious

Substances

Required Authorization Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Mailability Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager, and to

delete references to First-Class Mail

and First-Class Package Service.

22632 9-7-23

USPS

Packaging

Instruction 6D:

Sharps Waste

and Other

Regulated

Medical Waste

Required Authorization Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager.

22632 9-7-23

Mailability Revised to replace a reference to

merchandise returns service with a

reference to USPS Returns, delete a

reference to First-Class Mail, and to

replace a reference to Priority Mail

with a reference to Priority Mail

Return Service.

22632 9-7-23

Marking Revised to replace references to

merchandise returns service with

references to USPS Returns Service.

22632 9-7-23

USPS

Packaging

Instruction 6F:

Forensic

Material

Mailability Revised to reflect a title change to

director for the Postal Service

Product Classification and the

Pricing and Classification Service

Center (PCSC) manager, and to

delete references to First-Class Mail

and First-Class Package Service.

22632 9-7-23

The chapter,

subchapter,

part, appendix,

or section… titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

USPS

Packaging

Instruction 10A:

Small Quantity

Provision

Small Quantity Provision Revised to include a hyphen between

the words “small” and “quantity” in

the title and text.

22632 9-7-23

Required Packaging:

Inner Receptable

Revised to add inner-receptable

quantity limits in the associated

small-quantity packaging

instructions.

22632 9-7-23

Appendix D, Hazardous Materials Definitions

Appendix D Air transportation Revised to update the definition of

“Air transportation.”

22632 9-7-23

Appendix G, Hazardous Materials Service Type Codes (STCs) and Extra Service Codes (ESCs)

Appendix G Hazardous Materials

Service Type Codes

(STCs) and Extra Service

Codes (ESCs)

Added to to incorporate new

requirements, which became

effective July 9, 2023, for mailers to

use unique Service Type Codes and

Extra Service Codes for package

shipments containing hazardous

material or dangerous goods.

22632 9-7-23

Index

Index Revised the section number

references of several entries to

reflect revisions in this Pub 52

edition.

22632 9-7-23

The chapter,

subchapter,

part, appendix,

or section… titled… was…

in Postal

Bulletin

issue

number…

with an

issue

date of…

Transmittal Letter

Hazardous, Restricted, and Perishable Mail

Publication 52 September 7, 2023

Transmittal Letter

A. Purpose. Publication 52, Hazardous, Restricted, and Perishable Mail, provides

important information to help mailers determine what may be mailed and how certain

items must be packaged to keep the mail safe. It also provides guidance to Postal

Service™ employees accepting this mail.

Publication 52 is available on Postal Explorer

at http://pe.usps.com.

Customers may also consult their local postmaster or manager of business mail entry

for additional information about hazardous materials in the mail.

B. Effective Date. This edit

ion is effective September 7, 2023. All previous issues of

Publication 52 are obsolete.

C. Availability.

Public: The public can access Publication 52 in PDF and

HTML formats on Postal

Explorer at

http://pe.usps.com.

Postal Service: Postal Service employees can access Publication 52 in PDF and HTML

formats on the USPS Web site.

D. How to Use This Book. An in

troduction is located at the beginning of the book. It

explains the purpose and scope of the book, as well as the need to protect Postal

Service employees and customers from potentially dangerous materials in the mail. In

the appendices, we have included a hazardous materials table, packaging instructions

for mailable materials, and a glossary of terms.

E. Comments. Contact

your local Post Office

™

, business mail entry office, or the Pricing

and Classification Service Center (PCSC) with comments or questions about our mailing

standards (see DMM 608.8.4 for addresses and telephone numbers of business mail

entry offices and the PCSC).

Steven W. Monteith

Chief Customer and Marketing Officer

and Executive Vice President

September 7, 2023 iii

Contents

Summary of Changes

Transmittal Letter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

11 Purpose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

111 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

112 Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

113 Other Reference Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

12 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

121 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

122 Hazardous, Restricted, and Perishable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

123 Mailability Premise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

123.1 Basic Premise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

123.2 Restricted Matter — General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

123.3 Harmful Matter — General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

123.4 Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

123.5 Other Nonmailable Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

13 Additional Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

14 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

15 Protecting Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

16 Military Postal System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

17 Statutory System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

18 Trademarks of the USPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

181 Use of USPS Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

182 Common Law Marks or USPS Marks with Pending Trademark Applications . . . . . . . . 8

2 General Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

21 Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

211 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

212 Mailer Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

213 Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

214 Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

215 Requests for Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

215.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

215.2 Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

215.3 Restricted Matter or Perishable Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

216 Nonmailable Matter Found in the Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Hazardous, Restricted, and Perishable Mail

iv Publication 52

22 Marking Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

221 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

221.1 Address Side of Mailpiece. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

221.2 Ancillary Endorsements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

222 Matter Excepted From Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

223 Hazardous Materials Warning Labels and Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

224 Tag 44 for Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

225 Other Postal Service Labels and Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

226 Package Orientation Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

227 Old Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

228 Shipping Papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

23 Handling Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

231 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

232 Nonmailable Hazardous Materials Found in the Mailstream . . . . . . . . . . . . . . . . . . . . . 16

24 Emergency Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

241 General Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

242 Hazard Duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

243 Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

244 Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

245 Hazardous Chemical Emergencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

246 Emergency Telephone Numbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

25 Basic Guidelines for Postal Service Personnel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

251 Guidelines for Acceptance Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

252 Guidelines for Dispatch Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

253 Guidelines for Delivery and Collection Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

3 Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

31 Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

32 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

321 U.S. Department of Transportation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

322 Postal Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

323 Mailer Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

323.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

323.2 Service Type Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

323.3 Extra Service Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

323.4 Additional GS1 DotMatrix (2D) IMpb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

323.5 Shipping Service File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

323.6 Legacy Postage and Hard-Copy Postage Statements . . . . . . . . . . . . . . . . . . . . . . 23

323.7 USPS-Generated Shipping Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

324 Mailability Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

325 DOT Hazardous Materials Warning Labels and Markings . . . . . . . . . . . . . . . . . . . . . . . 24

325.1 General Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

325.2 Nonmailable Warning Labels and Marks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Contents

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325.3 Mailable Warning Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

325.4 Limited Quantity Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

325.5 Excepted Quantity Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

326 Shipping Papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

327 Transportation Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

327.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

327.2 Air Transportation Prohibitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

328 Postal Service Hazardous Materials Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

329 Presentation of Hazardous-Materials Mailings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

33 Hazard Classes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

331 Nine Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

332 Limited Quantity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

333 Consumer Commodity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

334 USPS Limited Quantity Air Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

335 ID8000 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

336 USPS Limited Quantity Surface Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

337 Excepted Quantity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

337.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

337.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

337.3 Additional Restrictions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

337.4 Quantities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

337.5 Packaging and Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

338 Small Quantity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

338.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

338.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

338.3 Additional Restrictions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

338.4 Packaging and Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

339 Packaging Requirements for Hazardous Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

339.1 DOT Packing Groups. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

339.2 Postal Service Packaging Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

34 Mailability by Hazard Class. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

341 Explosives (Hazard Class 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

341.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

341.2 Mailability, Packaging, and Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

342 Gases (Hazard Class 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

342.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

342.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

342.3 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

342.4 Marking and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

342.5 Mailability Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

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343 Flammable and Combustible Liquids

(Hazard Class 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

343.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

343.2 Mailability and Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

343.3 Marking and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

344 Flammable Solids (Hazard Class 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

344.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

344.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

344.3 Packaging, Marking, and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

345 Oxidizing Substances, Organic Peroxides

(Hazard Class 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

345.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

345.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

345.3 Packaging, Marking, and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

346 Toxic Substances and Infectious Substances (Hazard Class 6). . . . . . . . . . . . . . . . . . . 54

346.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

346.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

346.3 Packaging, Marking, Labeling, and Documentation . . . . . . . . . . . . . . . . . . . . . . . . 62

346.4 Damaged Parcels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

347 Radioactive Materials (Hazard Class 7). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

347.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

347.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

347.3 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

347.4 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

347.5 Emergency Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

348 Corrosives (Hazard Class 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

348.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

348.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

348.3 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

348.4 Marking and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

349 Miscellaneous Hazardous Materials

(Hazard Class 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

349.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

349.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

349.3 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

349.4 Marking and Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

4 Restricted Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

41 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

411 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

412 Mailer Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

413 Rulings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

414 Nonmailable Matter Found in the Mails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

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42 Intoxicating Liquors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

421 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

422 Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

422.1 Nonmailable Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

422.2 Mailable Liquors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

423 Packaging and Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

423.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

423.2 Denatured Flammable or Combustible Liquor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

43 Firearms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

431 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

431.1 Firearm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

431.2 Handguns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

431.3 Antique Firearm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

431.4 Rifles and Shotguns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

431.5 Federal Firearms Licensee (FFL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

431.6 Air Guns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

432 Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

432.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

432.2 Handguns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

432.3 Rifles and Shotguns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

432.4 Indemnity Claims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

433 Legal Opinions on Mailing Firearms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

434 Replica or Inert Explosive Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

435 Nonmailable Firearms Found in the Mails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

44 Knives and Sharp Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

441 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

441.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

441.2 Switchblade Knife . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

442 Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

443 Packaging and Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

443.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

443.2 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

444 Nonmailable Knives in the Mails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

45 Other Restricted Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

451 Liquids, Powders, and Odor-Producing Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

451.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

451.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

451.3 Packaging and Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

452 Motor Vehicle Master Keys and Locksmithing Devices . . . . . . . . . . . . . . . . . . . . . . . . . 108

452.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

452.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

452.3 Packaging and Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

452.4 Nonmailable Matter Found in the Mails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

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453 Controlled Substances and Drugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

453.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

453.2 Mailer Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

453.3 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

453.4 Packaging and Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

453.5 Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

453.6 Nonmailable Matter Found in the Mails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

453.7 Mail-back Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

453.8 Undeliverable Medicines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

454 Unsolicited Promotional Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

454.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

454.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

454.3 Certificate Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

454.4 Customer Objection to Unsolicited Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

454.5 Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

455 Building Construction Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

455.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

455.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

455.3 Rulings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

455.4 Nonmailable Matter Found in the Mails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

456 Lottery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

456.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

456.2 Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

456.3 Nonmailable Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

46 Animal-Fighting Ventures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

461 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

461.1 Animal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

461.2 Animal-Fighting Venture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

461.3 Animal-Fighting Accessory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

461.4 Animal-Fighting Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

462 Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

47 Cigarettes, Smokeless Tobacco, and Electronic Nicotine Delivery Systems. . . . . . . . . . . . . 120

471 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.1 Cigarette . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.2 Smokeless Tobacco . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.3 Cigar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.4 Roll-Your-Own Tobacco . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.5 Electronic Nicotine Delivery System (ENDS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.6 Covered Product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

471.7 Consumer Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

471.8 State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

471.9 Minimum Age. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

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472 Covered Products Generally Nonmailable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

472.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

472.2 Treatment of Nonmailable Covered Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

472.3 Reasonable Cause to Suspect Covered Products . . . . . . . . . . . . . . . . . . . . . . . . . 122

472.4 Applicability of Other Laws and Regulations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

472.5 Recordkeeping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

473 Mailability Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

473.1 Scope of Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

473.2 Intra-Alaska and Intra-Hawaii Shipments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

473.3 Exception for Business/Regulatory Purposes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

473.4 Exception for Certain Individuals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

473.5 Consumer-Testing Exception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

473.6 Public Health Exception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

473.7 Suspension or Revocation of Eligibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

474 Additional Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

474.1 Interpretative Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

474.2 Exclusion of Products Approved for Tobacco Cessation or

Therapeutic Purposes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

5 Perishable Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

51 Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

511 General Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

512 Federal Statutes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

52 Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

521 General Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

522 Packaging and Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

522.1 Container Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

522.2 Security and Ventilation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

522.3 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

523 Acceptance for Mailing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

524 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

525 Nonmailable Live Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

525.1 Live Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

525.2 Live, Warm-Blooded Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

525.3 Reptiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

525.4 Poisonous Insects and Spiders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

526 Mailable Live Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

526.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

526.2 Live Bees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

526.3 Live, Day-Old Poultry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

526.4 Adult Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

526.5 Live Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Hazardous, Restricted, and Perishable Mail

x Publication 52

526.6 Small, Harmless, Cold-Blooded Animals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

526.7 Dead Animals or Parts of Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

53 Fresh Foods and Other Perishables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

54 Eggs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

55 Meats and Meat Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

56 Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

561 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

562 Quarantines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

562.1 Types of Quarantines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

562.2 Specific Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

562.3 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

562.4 Penalties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

563 Packaging and Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

563.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

563.2 Securing Tops of Bundles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

564 Further Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

57 Nonmailable Plant Pests, Injurious Animals, and Illegally Taken Fish or Wildlife . . . . . . . . . . 146

571 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

572 Criminal Penalties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

6 International Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

61 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

611 Refusal by Air Carrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

62 Hazardous Materials: International Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

621 General Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

621.1 Mailing Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

621.2 Hazard Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

621.3 Limited Quantity Air and Limited Quantity Ground . . . . . . . . . . . . . . . . . . . . . . . . . 148

621.4 APO/FPO/DPO Mail. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

621.5 Extra Service Codes and Shipping Service Files . . . . . . . . . . . . . . . . . . . . . . . . . . 149

622 Mailable Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

622.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

622.2 Biological Substances, Division 6.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

622.3 Radioactive Materials, Class 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

622.4 Magnetized Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

622.5 Lithium and Lithium-ion Cells and Batteries — General . . . . . . . . . . . . . . . . . . . . . 151

623 Nonmailable Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

63 Restricted Matter: International Mail. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

631 APO/FPO/DPO Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

632 Firearms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

632.1 Export to APOs/FPOs/DPOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

632.2 Import . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

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633 Inert Replica and Explosive Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

634 Knives and Sharp Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

635 Drugs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

636 Controlled Substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

637 Other Restricted Matter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

64 Perishable Matter: International Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

641 APO/FPO/DPO Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

642 Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

643 Eggs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

643.1 Fresh Eggs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

643.2 Dried Whole Eggs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

644 Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

645 Fresh Foods and Other Perishables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

7 Air Transportation Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

71 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

711 Refusal by Air Carrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

711.1 Air Carrier Policy or Pilot’s Decision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

711.2 Handling of Mailpieces Refused by an Air Carrier. . . . . . . . . . . . . . . . . . . . . . . . . . 162

72 Hazardous Materials: Air Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

721 General Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

722 Additional Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

722.1 APO/FPO/DPO Mail. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

722.2 ZIP Codes Served Only by Air Transportation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

722.3 Air Transportation Prohibitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

723 Hazardous Materials Warning Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

724 Consumer Commodity and Mailable Limited Quantity Materials . . . . . . . . . . . . . . . . . . 165

725 Mailer Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

725.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

725.2 Warning Labels and Marking Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

725.3 Shipping Papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

725.4 Addressing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

726 Postal Service Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

726.1 Acceptance Personnel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

726.2 Dispatch Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

727 Refusal by Air Carrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

727.1 Nonmailable or Improperly Prepared Mailpieces . . . . . . . . . . . . . . . . . . . . . . . . . . 168

728 Spills and Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

73 Restricted Matter: Air Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

731 Refusal by Air Carrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

Hazardous, Restricted, and Perishable Mail

xii Publication 52

74 Perishable Matter: Air Transportation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

741 General Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

742 Live Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

742.1 Basic Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

742.2 Bees. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

742.3 Refusal by Air Carrier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

743 Perishable Matter with Dry Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Appendix A — Hazardous Materials Table: Postal Service Mailability

Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

Appendix B — Numerical Listing of Proper Shipping Names by

Identification (ID) Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Appendix C — USPS Packaging Instructions for Mailable Hazardous

Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337

Appendix D — Hazardous Materials Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . 403

Appendix E — References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413

Appendix F — Alaska Routes Serviced by Air Transportation Only . . . . . . . . . . 415

Appendix G — Hazardous Materials Service Type Codes (STCs) and

Extra Service Codes (ESCs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421

September 7, 2023 xiii

Exhibits

Exhibit 226

Package Orientation Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Exhibit 227

Reused Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Exhibit 325.2

DOT Hazardous Materials Warning Labels: PROHIBITED IN THE MAIL . . . . . . . . . . . . . . . . . . . . . . 25

Exhibit 325.3a

DOT Hazardous Materials Warning Labels: PERMITTED ON MAILABLE HAZARDOUS

MATERIALS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Exhibit 325.3b

DOT Hazardous Material Warning Labels: PERMITTED FOR MAILABLE LIMITED QUANTITIES

ONLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Exhibit 325.4

DOT Hazardous Material Warning Labels: PERMITTED FOR LIMITED QUANTITY

SQUARE-ON-POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Exhibit 325.5

Excepted Quantity Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Exhibit 326

Shipper’s Declaration for Dangerous Goods (Sample Form) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Exhibit 331

DOT Hazard Classes and Postal Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Exhibit 343.21

Flammable Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Exhibit 343.22

Combustible Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Exhibit 346.12a2

Mailpiece Symbol and Marking for Mailpieces Containing Biological Substance, Category B

Substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Exhibit 346.321

International Biohazard Symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Exhibit 346.322c3

Shipping Paper for Regulated Medical Waste and Sharps Waste Containers . . . . . . . . . . . . . . . . . . 68

Exhibit 346.327

Packaging References for Mailable Materials, Infectious Substances

(Hazard Class 6, Division 6.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Exhibit 347.22

Activity Limits for Mailable Instruments, Articles, and Limited Quantity Radioactive Materials . . . . . 78

Exhibit 347.5c(1)

DOE Regional Coordinating Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Exhibits

September 7, 2023 xiv

Exhibit 349.222

Domestic Lithium Battery Mailability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Exhibit 349.242b

Warning Label for Magnetized Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Exhibit 432.25

Mailability Requirements for Handguns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Exhibit 526.21

Requirements for Mailing Live Bees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Exhibit 526.33

Requirements for Mailing Live, Day-Old Poultry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Exhibit 526.5

Restrictions on Mailing Live Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Exhibit 526.6

Requirements for Mailing Small, Harmless, Cold-Blooded Animals (Except Snakes, Turtles,

and Turtle Eggs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Exhibit 526.7

Requirements for Mailing Dead Animals or Parts of Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Exhibit 621.1

DOT Hazard Classes and Mailability for International Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Exhibit 622.5

International Lithium Battery Mailability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

Exhibit 643.22

Certificate of Mailing Dried Whole Eggs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Domestic Lithium Battery Mailability Exhibit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392

International Lithium Battery Mailability Exhibit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395

September 7, 2023 1

1 Introduction

11 Purpose

111 General

The purpose of this publication is to provide information and guidance when

mailing potentially hazardous, restricted, or perishable matter to domestic

and international destinations.

Certain potentially undesirable, harmful, or dangerous matter is nonmailable

by statute or regulation. The standards for nonmailable articles and

substances and the special conditions under which some of these articles

and substances may be mailed can be found in this publication.

These regulations apply to the military postal system, its employees, and

undelivered mail that is or has been in the official custody of this system and

its employees.

The regulations for nonmailable matter in written, printed, or graphic form are

covered in DMM 601.8.0, 508.9.0, and 508.10.0.

112 Use

This publication is designed for use by mailers and for employees in business

mail entry, retail units, marketing, and other functional areas that are involved

with providing mailability information to Postal Service customers.

Follow the standards contained in this publication when deciding whether

and under what conditions hazardous materials, restricted matter, and

perishable matter are permitted to be mailed.

The content of this publication is based on former DMM standards which

have been incorporated into this publication, as well as regulations of federal

agencies in effect at the time of publication. Future changes to the federal

regulations may supplement, amend, or supersede the content of this

publication.

113 Other Reference Sources

Note: No single guide could provide all the details necessary for the safe

acceptance and handling of every item that is classified as hazardous

material, restricted matter, or perishable matter. This publication

provides specific mailability requirements, where possible, for those

categories of harmful materials that present significant danger or which

are frequently presented for mailing.

113 Hazardous, Restricted, and Perishable Mail

2 Publication 52

Particular matter may be mailable under postal statutes and regulations, but

customers may have responsibilities under nonpostal statutes and

regulations concerned with possession, treatment, transmission, or transfer

of such matter (e.g., 49 CFR 100-185 [Department of Transportation

Regulations]; the Comprehensive Drug Abuse Prevention and Control Act of

1970 [Public Law 91-513], 21 U.S.C. 801, et seq.; and the Gun Control Act of

1968 [Public Law 90-618], 18 U.S.C. 921, et seq.).

In writing this publication, the following sources were used:

Postal Service

 Mailing Standards of the United States Postal Service, Domestic Mail

Manual (DMM).

 Mailing Standards of the United States Postal Service, International

Mail Manual (IMM).

 Postal Operations Manual (POM).

 Administrative Support Manual (ASM).

 Publication 14, Prohibitions and Restrictions on Mailing Animals,

Plants, and Related Matter.

 Handbook EL-812, Hazardous Materials and Spill Response.

 Aviation Mail Security, Management Instructions.

 Notice 107, Let’s Keep the Mail Safe.

 Poster 298, DOT Hazardous Materials Warning Labels and Markings.

Other Sources

 Title 18 of the United States Code (U.S.C.) 921, 1715, 1716

(18 U.S.C. 921, 1715, 1716).

 39 U.S.C. 3001-3002a, 3005, 3008-3010, 3012, 3014, 3015, 3017,

3018.

 21 U.S.C. 801–830 (drugs).

 7 U.S.C. 7701 (plant pests).

 7 U.S.C. 7760 (plants).

 Title 29 Code of Federal Regulations (29 CFR), Occupational Safety

and Health Administration (OSHA), U.S. Department of Labor.

 42 CFR, Department of Health and Human Services (HHS), Centers for

Disease Control and Prevention (CDC).

 49 CFR, Parts 100–185, U.S. Department of Transportation (DOT).

 International Civil Aviation Organization (ICAO), Technical Instructions

for the Safe Transport of Dangerous Goods by Air.

 International Air Transport Association (IATA), Dangerous Goods

Regulations.

Where appropriate, the names and addresses of agencies where more

detailed information can be obtained are provided in this publication.

Introduction 122

September 7, 2023 3

12 Scope

121 General

The scope of this publication extends to all articles and materials that are

nonmailable because they may harm people or property or that have mailing

restrictions imposed upon them by the regulations of other governmental

agencies.

Under 18 U.S.C. 1716 all matter that is outwardly or of its own force

dangerous or injurious to life, health, or property is nonmailable. The knowing

deposit of such matter in the mail is a crime punishable by fine,

imprisonment, or other penalty. However, certain hazardous materials and

otherwise restricted and perishable matter may be mailed under the

conditions permitted in this publication.

122 Hazardous, Restricted, and Perishable

The following are examples of hazardous materials, restricted matter, and

perishable matter. These are not complete lists, but they provide an idea of

the types of articles included in each category.

a. Hazardous materials (section 3) include:

(1) Explosives.

(2) Gases.

(3) Flammable liquids and combustible liquids.

(4) Flammable solids.

(5) Oxidizers and organic peroxides.

(6) Toxic substances (poisons) and infectious substances, etiologic

agents, clinical specimens, biological products, sharps, other

used medical devices.

(7) Radioactive materials.

(8) Corrosives.

(9) Miscellaneous hazardous materials (e.g., lithium batteries, dry

ice, magnetized materials).

b. Restricted matter (section 4) includes:

(1) Intoxicating liquors.

(2) Firearms.

(3) Building construction materials.

(4) Liquids and powders.

(5) Matter emitting obnoxious odors.

(6) Cremated remains.

(7) Motor vehicle master keys.

(8) Controlled substances and drugs.

(9) Hemp and CBD products.

(10) Sharp objects (knives, switchblades, stilettos).

123 Hazardous, Restricted, and Perishable Mail

4 Publication 52

(11) Unsolicited promotional items.

(12) Tobacco products.

c. Perishable matter (section 5) includes:

(1) Dead animals or parts of animals.

(2) Eggs.

(3) Live animals.

(4) Meat and meat products.

(5) Plants and plant products.

123 Mailability Premise

123.1 Basic Premise

The basic premise of the postal mailability statutes is that anything “which

may kill or injure another, or injure the mails or other property...” is

nonmailable. Several statutory exceptions to this rule permit mailings of

otherwise nonmailable matter under specified conditions. Statutory

exceptions apply to live scorpions, poisonous drugs and medicines, poisons

for scientific use, switchblade knives, firearms, motor vehicle master keys,

locksmithing devices, and abortive and contraceptive devices. The statutes

also provide that the USPS may, by regulation, permit the mailing, under

required conditions of preparation and packing, of potentially harmful matter

not “outwardly or of [its] own force dangerous or injurious to life, health, or

property.” The regulations in this publication summarize the statutory

prohibitions and exceptions; detail the mailability standards that apply to

perishable, hazardous, and restricted matter; contain information on the

mailability of specific hazardous materials; and describe the conditions of

preparation and packaging under which the USPS accepts for mailing

potentially harmful matter that is otherwise nonmailable.

123.2 Restricted Matter — General

Restricted matter is an article or substance prohibited or limited by Title 18,

U.S. Code (liquors, abortive and contraceptive devices, odd-shaped items in

envelopes, motor vehicle master keys, and locksmithing devices). It also

includes matter not otherwise described in this publication that is restricted

by 18 U.S.C. 1716(a) because it may, under conditions encountered in the

mail, be injurious to life, health, or property (obnoxious odors, liquids,

powders, and battery-powered devices).

123.3 Harmful Matter — General

Except as provided in this publication, any article, composition, or material is

nonmailable if it can kill or injure another or injure the mail or other property.

Harmful matter includes, but is not limited to:

a. All types and classes of poisons, including controlled substances.

b. All poisonous animals except scorpions mailed for medical research

purposes or for the manufacture of anti-venom (or antivenin or

antivenene); all poisonous insects; all poisonous reptiles; and all types

of snakes, turtles, and spiders.

Introduction 14

September 7, 2023 5

c. All disease germs or scabs.

d. All explosives, flammable material, infernal machines, and mechanical,

chemical, or other devices or compositions that may ignite or explode.

123.4 Hazardous Materials

Harmful matter also includes regulated hazardous materials that are likely to

harm USPS employees or to destroy, deface, or otherwise damage mail or

postal equipment. This includes materials such as caustic poisons (acids and

alkalis), oxidizers, or highly flammable liquids, gases, or solids; or materials

that are likely, under conditions incident to transportation, to cause fires

through friction, absorption of moisture, or spontaneous chemical changes

or from retained heat from manufacturing or processing, including explosives

or containers previously used for shipping high explosives with a liquid

ingredient (such as dynamite), ammunition, fireworks, radioactive materials,

matches, or articles emitting obnoxious odors.

123.5 Other Nonmailable Matter

Matter is nonmailable also when it cannot be delivered because of an

illegible, incorrect, or insufficient address, or when it does not meet USPS

standards for mail preparation, classification, postage prices, size, or weight.

13 Additional Information

Although the Postal Service makes every effort to inform its customers of the

mailability of particular harmful matter via the DMM standards and the

information in this and other publications, it is the responsibility of the mailer

to fully meet all requirements prior to mailing. See

212 for more complete

information on the responsibilities of mailers.

The authority of Postal Service personnel to decide whether particular

articles or substances presented for mailing are nonmailable is stated in

213.

14 Safety

The handling and transport of hazardous materials, restricted matter, and

perishable matter involves added levels of risk. That risk can become even

greater if a nonmailable material is mailed or if the packaging of a mailable

material is not adequate to prevent damage or spillage during normal

handling.

Under no circumstances may any nonmailable hazardous material, restricted

matter, or perishable matter be deposited for mailing. Mailable items must be

packaged and labeled as required in the applicable DMM standards and the

regulations in this publication.

15 Hazardous, Restricted, and Perishable Mail

6 Publication 52

A Postmaster may take any step reasonable and necessary to protect USPS

employees and equipment from potentially dangerous or injurious materials

or substances found in the mail. USPS employees may refuse an article for

mailing if the content of the article is described by the mailer or otherwise

revealed to be nonmailable.

The Postal Service’s primary purpose in requiring proper packaging,

identification, and deposit of mailable hazardous materials, restricted matter,

or perishable matter is to ensure the safety of our employees and the general

public who may come into contact with these mailpieces. These

requirements also are intended to ensure the safety of Postal Service

equipment and facilities.

15 Protecting Personnel

All reasonable and necessary steps must be taken to protect Postal Service

personnel and equipment from the effects of potentially dangerous or

injurious materials or substances found in the mail, as stated in ASM 223.4.

16 Military Postal System

Unless excepted, standards in this publication apply to the military postal

system, its personnel, and undelivered mail that is or has been in the official

custody of that system and its personnel. References to the Inspection

Service refer to the Postal Inspection Service and its authorized employees,

not to military investigative services.

17 Statutory System

18 U.S.C. 2510, et seq., constitutes a statutory system of regulating

interception of wire, oral, or electronic communications. Any person

contemplating the mailing of a device primarily useful for surreptitiously

effecting such interception should consider the provisions of 18 U.S.C. 2510,

et seq., particularly section 2512. This statute makes it a crime, except as

otherwise provided in 18 U.S.C. 2510, et seq., for a person intentionally to

send through the mail any device whose design that person knows, or has

reason to know, renders the device primarily useful for surreptitious

interception of wire, oral, or electronic communications. The statute does not

declare that such a device in itself constitutes nonmailable matter but, as

indicated, provides criminal penalties for the act of intentionally mailing it.

Introduction 181

September 7, 2023 7

18 Trademarks of the USPS

181 Use of USPS Trademarks

USPS trademarks must be used in the form listed in this section. Proper use

of any USPS trademarks may require capitalizing the initial letters, or all the

letters of the acronym, to distinguish them from terms not used as

trademarks. Words and phrases that are registered trademarks may also use

the registration symbol

; words and phrases that are not registered but are

still USPS trademarks may use the ™ symbol. If the registration or ™ symbol

is not used, a reference should be placed at the beginning or end of the

document, indicating the marks that are used in the publication with the

following notation: “The following marks are among the many marks

belonging to the U.S. Postal Service and are not an exhaustive list”:

We list the marks in lieu of using the

symbol throughout Publication 52.

1-800-Ask-USPS FastForward Parcel Select Standard Mail

Air Mail First-Class Mail Parcel Select Lightweight U.S. Postage Paid

Business Reply Mail First-Class Mail

International

PC Postage The Postal Service

Certified Mail Forever PFS The Postal Store

Click-N-Ship Global Express

Gua

ranteed

Pickup on Demand U.S. Postal Service

Click-N-Ship for Business GXG Postal Explorer United States Postal

Service

Commercial Base IMb PostalPro USPS

Commercial Plus IMb Tracing Premium Forwarding

Service

USPS Delivery

Conf

irmation

Critical Mail IMM Priority Mail USPS Electronic Postmark

DMM Intelligent Mail Priority Mail Express USPS ePacket

EDDM International Surface Air

Priority Mail Flat Rate USPS Package Intercept

EDDM Retail IPA Priority Mail International USPS Returns

ePacket ISAL Priority Mail Open and

Dist

ribute

USPS Web Tools

EVS Market Mail Priority Mail Regional Rate USPS.com

e-VS Media Mail Priority Mail Regional Rate

Box

ZIP

Express Mail International MERLIN Priority Mail Returns ZIP+4

FAST Parcel Post Return to Sender

182 Hazardous, Restricted, and Perishable Mail

8 Publication 52

182 Common Law Marks or USPS Marks with Pending

Trademark Applications

The following is a list of Common Law Marks or USPS marks with pending

trademark applications that appear throughout Publication 52. The ™ may be

used after these marks and the same trademark rules apply whenever these

services or terms appear in the DMM. Note: this list changes frequently and

some of these marks will become registered and require the

ACS M-Bag Priority Mail 3-Day Delivery Registered Mail

Carrier Pickup Open and Distribute Priority Mail 3-Day Delivery

aranteed

Signature Confirmation

CASS Parcel Select

Regional Ground

Priority Mail 3-Day USPS Retail Ground

CASS Certified P.O. Box Priority Mail Express U.S. Mail

Courtesy Reply Mail PO Box Priority Mail Express 1-Day US Postage Paid

Delivery Confirmation Post Office Priority Mail Express 2-Day US Postal Service

FCPIS Post Office Box Priority Mail Express 3-Day USPS

First-Class Postal Service Priority Mail Express DPO USPSCA

First-Class Package Postmaster General Priority Mail Express Flat

te Box

USPS Corporate Account

First-Class Package

International Service

POSTNET Priority Mail Express

International

USPS Picture Permit

First-Class Package Service Priority Mail 1-Day

livery

Priority Mail Express

Military

USPS Tracking

IMb Priority Mail 1-Day

Delivery Guaranteed

Priority Mail Express

Offshore

USPSCA

IMb Tracing Priority Mail 1-Day Priority Mail Express Open

and Distribute

ZIP Code

IMRS Priority Mail 2-Day

livery

Priority Mail International

International Business Reply Priority Mail 2-Day

Delivery Guaranteed

QBRM

International Priority Airmail Priority Mail 2-Day Qualified Business Reply

September 7, 2023 9

2 General Guidelines

21 Mailability

211 General

Under 18 U.S.C. 1716, all matter that is outwardly or of its own force

dangerous or injurious to life, health, or property is nonmailable. The knowing

deposit of such matter in the mail is a crime punishable by fine,

imprisonment, and/or other penalty.

For reasons of safety, most hazardous materials are nonmailable. However,

some hazardous materials and otherwise restricted matter, or perishable

matter are permitted to be mailed when the requirements in this publication

are fully met.

Chapter 3, Appendix A, and Appendix C of this publication provide detailed

information about hazardous materials that are permitted to be mailed and

the conditions that apply.

Chapters 4 and 5 of this publication provide information about restricted

matter and perishable matter that either is nonmailable or that may be

mailable under specified conditions, as applicable.

Chapter 6 specifies the mailing conditions that apply to hazardous materials,

restricted matter, and perishable matter in international mail, including

hazardous materials for delivery to overseas military and diplomatic Post

Office (APO/FPO/DPO) addresses.

Chapter 7 contains information regarding mailability of hazardous materials,

restricted matter, and perishable matter in domestic mail via air

transportation.

Regardless of content, a mailpiece bearing only postage stamps as the

postage payment method and weighing more than 10 ounces or measuring

more than one-half inch thick may not be deposited into a collection box,

Postal Service lobby drop, Postal Service dock, customer mailbox, or other

unattended location. A city, rural, or highway contract letter carrier may not

pick up these mailpieces for delivery, either from an individual or through

Pickup on Demand service. The sender must present such items to an

employee at a retail service counter in a Postal Service facility. Improperly

presented items will be returned to the sender for proper entry and

acceptance.

212 Hazardous, Restricted, and Perishable Mail

10 Publication 52

212 Mailer Responsibility

All mailers, including mail service providers and other mailer agents, must

comply with applicable Postal Service laws and regulations governing

mailability and preparation for mailing, as well as nonpostal laws and

regulations on the shipment of particular matter.

The Postal Service disseminates information about mailing standards by

publishing the DMM and IMM and by providing this and other publications

that give additional guidance to mailers.

Mailers need to be aware of current or new regulations adopted by the Postal

Service and other governmental agencies.

213 Authority

A Postmaster has the authority to decide whether articles and substances

other than written, printed, or graphic matter are nonmailable and, where

appropriate, is authorized to refuse to accept for mailing such matter

determined to be nonmailable. Postmasters may consult with the Pricing and

Classification Service Center (PCSC) in making these determinations.

PRICING AND CLASSIFICATION SERVICE CENTER

90 CHURCH ST STE 3100

NEW YORK NY 10007-2951

TELEPHONE: (212) 330-5300 / FAX: (212) 330-5320

214 Appeals

A mailer who receives an adverse decision from a postmaster may file a

written appeal with the PCSC (see

213 for address), which issues the final

agency decision. After the PCSC issues an initial ruling, the mailer may

appeal to the director, Product Classification, USPS Headquarters,

Washington, DC, who has the authority to render a final decision on the

appeal.

Mailers may file a written appeal of a final Postal Service agency decision

with the USPS Recorder, Judicial Officer, under the rules of procedure in

CFR 953.

DIRECTOR, PRODUCT CLASSIFICATION

U.S. POSTAL SERVICE

475 L’ENFANT PLAZA SW RM 4446

WASHINGTON DC 20260-5015

RECORDER

JUDICIAL OFFICER

U.S. POSTAL SERVICE

2101 WILSON BLVD STE 600

ARLINGTON VA 22201-3078

General Guidelines 215.2

September 7, 2023 11

215 Requests for Rulings

215.1 General

Mailability decisions are based on Postal Service statutes and regulations in

effect at the time the ruling is issued. Over time, some rulings may become

obsolete or require modification to conform to changes in applicable laws

and regulations. When rulings are issued, the requirements of other

governmental agencies (e.g., U.S. Department of Transportation, Centers for

Disease Control and Prevention) may be taken into consideration to the

extent that they are consistent with Postal Service policy and authority.

Requests for rulings must contain specific items of critical information

appropriate to the category of the material, as noted in

215.2, 215.3, and 324.

215.2 Hazardous Materials

Acceptability for mailing hazardous materials depends on many factors, such

as the container fluid/vapor capacities, the ability of the complete mailpiece

to contain the material, and the method of absorbing and containing the

material in case of accidental leakage of the primary receptacle.

To determine mailability of a specific material, a mailer must submit a

material safety data sheet (MSDS) (see Appendix

D) and the following

information to the PCSC (see 213 for address):

a. Common and proper shipping name of the material, hazard class, and

the assigned United Nations (UN) or North American (NA) identification

number.

b. Chemical composition by percentage of weight.

c. Flashpoint.

d. Toxic properties.

e. Irritant action when inhaled, swallowed, or with contact to skin or eyes.

f. Special precautions necessary to permit handling without harm to

USPS employees or damage to property or other mail.

g. Explanation of warning labels and shipping papers required by local,

state, or federal regulations.

h. Description of the proposed packaging method, including the

addressing, required markings, and documentation.

i. Volume of material per mailpiece, proposed number of pieces to be

mailed, class of mail, and post office(s) of mailing.

The hazards present with chemicals and other types of hazardous materials

may not be readily apparent. Materials classified under one hazard class can

present additional or subsidiary hazards more commonly associated with a

different hazard class. For example, swimming pool chemicals may cause

fires or release poisonous fumes or be corrosive or poisonous. Therefore, it is

essential when determining mailability to correctly identify the material based

on the mailer-supplied documentation (i.e., the MSDS and other information)

and never to assume a general designation using unsubstantiated

information.

215.3 Hazardous, Restricted, and Perishable Mail

12 Publication 52

215.3 Restricted Matter or Perishable Matter

To obtain a ruling on the mailability of restricted or perishable matter, a mailer

should provide the mailing office with following:

a. Detailed description of the restricted or perishable matter.

b. Special precautions necessary to permit handling without harm to

Postal Service employees or damage to property.

c. Proposed method of packaging.

d. Explanation of any local, state, or federal regulations that apply to

shipping such matter.

e. Quantity per mailpiece and per mailing, frequency of mailing, and post

office(s) of mailing.

When information about restricted or perishable matter is insufficient to make

a mailability determination, or when there is doubt about the mailability of a

particular item, contact the PCSC.

216 Nonmailable Matter Found in the Mail

Specific items, such as firearms, switchblade knives, controlled substances,

motor vehicle master keys, and explosive or incendiary devices, generally are

prohibited for mailing. When these types of nonmailable items are found in

the mailstream, they must be handled in accordance with POM 139.117, by

referring to the Postal Inspection Service.

Other materials found in the mail that are believed to be nonmailable must be

treated under the applicable conditions in POM 139.117-18 and ASM 223.4.

22 Marking Requirements

221 General

To avoid rejection of the mailpiece by Postal Service acceptance personnel

or air carriers, mailers must ensure that their packages meet all applicable

labeling, marking, and ancillary endorsement requirements.

221.1 Address Side of Mailpiece

Hazardous materials and restricted or perishable matter, unless specifically

excepted in

222, must be clearly marked, labeled and identified on the

address side of the mailpiece (see 325.1 and DMM section 102.1.1 and

202.1.1). Only in limited situations where sufficient space does not exist,

DOT markings may be placed on a side adjacent to the address. Markings

and labels must not be placed on the bottom of a package or envelope.

Other markings required by the Postal Service or other federal regulatory

agencies also must appear on the address side of any mailpiece containing

hazardous material, restricted matter, or perishable matter as specified in

325.1. Required markings must be applied with an insoluble material or

other material that cannot be rubbed off or smeared.

General Guidelines 223

September 7, 2023 13

221.11 Return Address

Except for diagnostic specimen mailpieces using a Business Reply Mail

format, and nonregulated materials, a return address that includes the

sender’s name and address must appear on all packaging containing

hazardous, restricted, or perishable mail.

221.12 Content Markings

When required, the contents also must be clearly identified on the address

side. The contents must be disclosed to be mailable. A mailability

determination may be required based on the mailer’s disclosure concerning

the contents at the time of mailing.

221.2 Ancillary Endorsements

A mailer endorsement may be used to request forwarding, return, or

address-correction service for items that are undeliverable as addressed (see

DMM 507).

Mailpieces containing hazardous materials mailed via surface transportation

(

327.1b) must bear one of the following endorsements:

a. “Address Service Requested;”

b. “Forwarding Service Requested;” or

c. “Return Service Requested.”

Mailers are not permitted to use the endorsement “Change Service

Requested” for mailpieces containing hazardous materials.

222 Matter Excepted From Markings

If permitted to be mailed under Chapter 4, the following materials are

excepted from the content requirements in 221 and must be mailed with no

indication or identifying marking on the outside of the parcel:

a. Controlled substances and drugs.

b. Firearms.

c. Motor vehicle master keys.

d. Switchblade knives.

223 Hazardous Materials Warning Labels and Markings

Most hazardous materials permitted in the mail fall in the Limited Quantity/

Consumer Commodity categories. Eligible Limited Quantity materials

intended for surface transport must display a Limited Quantity (square-on-

point) surface marking. Limited Quantity materials intended for air transport

must display a DOT Limited Quantity marking square-on-point with the

symbol “Y’ in the center, and may also require a specific DOT diamond-

shaped hazardous material warning label and other markings. See

Exhibit

325.4. For specific information on hazardous materials warning labels and

marking requirements, see 325.

224 Hazardous, Restricted, and Perishable Mail

14 Publication 52

224 Tag 44 for Hazardous Materials

Category B infectious substances are the only type of hazardous materials

permitted to be placed in a sack or tub. All mailpieces must be properly

marked with the proper shipping name “Biological Substance, Category B”

and “UN3373” inside a diamond marking as outlined in

346.22a. A sack or

tub containing Category B infectious substances must have attached Tag 44,

ck Contents Warning. The tag must be removed when the Category B

infectious substances are no longer in the sack or tub. See Chapter

7 for

more information.

225 Other Postal Service Labels and Tags

The Postal Service provides these labels and tags for affixing to the outside

of mailpieces containing bees, live animals, or perishable matter:

a. Label 27, Bee Ware!

b. Label 28, Live Animals.

c. Tag 9, Perishable —

Do Not Delay.

d. Label 127, Sur

face Transportation Only.

226 Package Orientation Markings

Outer packaging that contains a primary receptacle (and secondary

packaging, when required) of a liquid or other spillable material must be

packed with the closure of the primary receptacle positioned upward.

The outer packaging must be plainly and legibly marked on two opposite

sid

es with a package orientation marking consisting of two underlined

arrows that point in the correct upright position.

Optionally, the two arrows may be enclosed in a rectangle. Specifications for

ckage orientation markings are in 49 CFR 172.312. See

Exhibit 226 for

examples.

Exhibit 226

Package Orientation Markings

Note: Either design is acceptable.

227 Old Markings

Under 49 CFR 173.29, a container that previously held a hazardous material

is considered the same as a full container of the material. A container

improperly identified by content is not acceptable for mailing. Some

potentially hazardous, restricted, and prohibited matter is nonmailable by

statute or regulation. Because of safety concerns and in compliance with

laws governing the transportation of hazardous, restricted, and prohibited

materials, as well as privacy statutes, the Postal Service must assume that all

markings and labels on a package identify the actual content.

General Guidelines 228

September 7, 2023 15

Reused packaging, boxes, and containers that bear inapplicable labels or

mar

kings associated with hazardous, prohibited, or restricted materials are

prohibited in the mailstream, unless the labels or markings have been

removed or completely obliterated. If the labels or markings can still be read

or identified, they are not sufficiently obliterated. See

Exhibit 227.

Exhibit 227

Reused Packaging

Incorrect Procedure

Correct Procedure

If labels or markings have not been sufficiently obliterated, the package must

be handled as though it contains the indicated contents. Frequently, these

types of packages must be handled as nonmailable hazardous materials and

must be isolated and removed from the mailstream.

Examples of commonly reused boxes include cleaning supply boxes and

liquo

r/wine/beer boxes. Some cleaning products are hazardous materials;

although most alcoholic beverages are not hazardous materials, they are

prohibited from mailing. Packages containing alcoholic beverages or with

alcoholic beverage markings are prohibited in the mail.

Postal Service employees may not remove, cross out, or obliterate labels or

mar

kings, even if asked to do so by a mailer. Only the mailer or mailer’s

authorized representative may alter or obliterate the labels or markings.

228 Shipping Papers

Mailable hazardous materials eligible to be sent by Priority Mail Express or

Priority Mail must be packaged, labeled, and appropriately documented for

air transportation, as required by federal regulations and subchapter

22.

Mailable hazardous materials sent via air transportation (except materials

iden

tified under

346.2) must be accompanied with a shipper’s declaration for

dangerous goods (shipping paper) co

mpleted in triplicate and signed by the

mailer.

Air carriers may reject mailpieces that are not accompanied by the required

shipp

ing papers. See

326 and Exhibit 326 and Chapter 7 for more

information.

23 Hazardous, Restricted, and Perishable Mail

16 Publication 52

23 Handling Hazardous Materials

231 General

A potentially dangerous situation exists whenever hazardous materials,

restricted matter, or perishable matter is being moved from one place to

another. Careless handling can result in serious injury to the general public

and Postal Service personnel, damage to other mail and Postal Service

equipment, and delays in processing and delivering mail.

The Postal Operations Manual (POM) provides additional instructions for

handling hazardous materials in the mail.

232 Nonmailable Hazardous Materials Found in the

Mailstream

When any mailpiece containing a nonmailable hazardous material is found in

the mailstream, the procedures in POM 139.117 must be followed if the

materials present an immediate threat to persons or property. When there is

no immediate threat to persons or property, follow the procedures in POM

139.118.

24 Emergency Procedures

241 General Requirements

Incidents involving the release of hazardous materials, restricted matter, or

perishable matter may cause death, injury, and damage to property. Such

incidents can be avoided or minimized if appropriate preventive measures

are taken or correct emergency procedures are followed.

MI EL-810-2006-3, Response to Hazardous Materials Releases, and

Handbook EL-812, Hazardous Materials and Spill Response, provide

guidelines for responding to emergency situations. Postal Service employees

involved in the flow of mailpieces containing harmful matter must follow

these guidelines from the point of deposit to the point of delivery.

242 Hazard Duration

Frequently, the effects of exposure resulting from damage, spillage, or

leakage of harmful matter are not obvious or readily apparent. For example,

infectious substances, radioactive material, corrosives, and poisons can

cause illness or injury that may become known to the victim gradually and

long after the incident.

General Guidelines 244

September 7, 2023 17

243 Precautions

During any spill or leak incident, or when damage is detected involving

harmful items, Postal Service personnel must take every precaution to

protect other personnel and property from visible and invisible effects of the

material involved. These procedures are to be followed:

a. Identify harmful properties of the material (based on the markings) and

determine the precautions to be taken.

b. Provide adequate personal protection to employees who must handle

the materials.

c. Contain and transport leaking containers for disposal.

d. Clean and decontaminate facilities and machinery.

Refer to MI EL–810–2006–3, Response to Hazardous Materials Releases, and

Handbook EL–812, Hazardous Materials and Spill Response, for specific

instructions.

244 Procedures

During any incident involving harmful matter where there is actual or

suspected damage to a mailpiece or its contents, Postal Service personnel

must follow the specific procedures in Handbook EL–812, Hazardous

Materials and Spill Response, and as outlined below:

a. Isolate the damaged package immediately and restrict the area. If the

incident occurs in a facility or on the equipment of an air carrier,

immediately brief the carrier on the nature and quantity of the materials

released.

b. Contact the supervisor or designated qualified employee, who can take

prompt and appropriate measures to protect life and prevent injury,

loss, or damage. They will determine whether it is an incidental spill

that can be handled by the facility spill and leak team or an emergency

spill that will require implementation of the emergency action plan. If

mail sealed against inspection must be opened for this purpose, act in

accordance with ASM 274.

c. Remove any injured or contaminated person from the area with as little

physical contact as possible:

(1) Limit any first aid to what is absolutely necessary, until a qualified

physician is present.

(2) Direct all personnel exposed to radioactive materials to wash all

exposed body areas immediately with cold water and

immediately report to a physician for an examination.

d. If the spill is determined to be an emergency, contact the fire

department, the police, a qualified physician, and/or the appropriate

agencies equipped to handle specific situations.

e. Avoid smoke, fumes, or dust. Segregate any clothing or tools used in

fighting fires until they can be checked for contamination.

f. Do not eat, smoke, or drink in the affected area.

g. Do not place involved areas in service until the appropriate authorities

have determined that the areas are free of all contamination.

245 Hazardous, Restricted, and Perishable Mail

18 Publication 52

h. Notify the PCSC or Postal Service Inspection Service, as appropriate

under POM 139.117–118 (see

216). A report must be made for any

incident that includes damage to mail or property, or injury to

personnel. An online Mailpiece Incident Report (MIR) must be

completed and filed in accordance with the instructions in the Safety

Toolkit, based on the incident type.

245 Hazardous Chemical Emergencies

CHEMTREC (Chemical Transportation Emergency Center) is a service of the

Chemical Manufacturers Association that provides immediate information

and advice 24 hours a day, 7 days a week, for those at the scene of

transportation emergencies involving chemicals.

Postal Service personnel are authorized to telephone CHEMTREC day or

night, toll free, at 800-424-9300. For calls originating within the state of

Virginia or outside the continental United States, telephone 703-527-3887.

CHEMTREC usually can provide hazard guidance and information warnings

when given only the name of the product and the nature of the problem.

CHEMTREC also follows up by promptly contacting the shipper of the

chemicals involved for more detailed assistance. CHEMTREC does not

provide on-site emergency response.

CHEMTREC may request the following information in an emergency call:

a. Caller’s name, title and organization, and callback number at scene.

b. Description of incident and actions taken.

c. Type and number of injuries/exposures.

d. Material involved, including:

(1) Name of the product(s), preferably a trade name.

(2) Shipper and point of destination.

(3) Consignee and destination (delivery address).

e. Type or description and number of containers/packages.

f. Specific information you need right away (MSDSs, medical help, etc.)

g. Size of or amount of release.

h. Location, time, weather at the scene.

246 Emergency Telephone Numbers

Following are telephone numbers for use during normal business hours

(unless otherwise noted) for the indicated types of emergencies:

CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC)

(for etiologic agents and biohazard materials) 404-633-5313

CHEMICAL TRANSPORTATION EMERGENCY CENTER

(CHEMTREC)

(for Chemical Spills - 24 hours a day, 7 days a week)

800-424-9300 (in continental United States; outside Virginia)

703-527-3887 (within Virginia or outside the continental United

States)

CROPLIFE AMERICA

(for Herbicides, insecticides, Fungicides, and similar products)

202-296-1585

General Guidelines 251

September 7, 2023 19

U.S. DEPARTMENT OF TRANSPORTATION (DOT)

NATIONAL RESPONSE CENTER

(for Chemical and Oil Spills)

202-267-2675 (within Washington DC)

800-424-8802 (outside Washington DC)

25 Basic Guidelines for Postal Service Personnel

251 Guidelines for Acceptance Personnel

Postal Service personnel may not open mail sealed against inspection

except under the circumstances described in ASM 274. Accordingly,

knowledge of the content of such mail may be obtained directly from the

mailer (e.g., a mailer may ask questions about mailing requirements or mark

the outside of the mailpiece to indicate the contents) or indirectly through

leakage or other escape of the contents. Subject to the applicable

restrictions, acceptance personnel must:

a. Determine the mailability of all hazardous materials, perishable matter,

or otherwise restricted matter offered for mailing at a retail unit or

business mail entry unit (BMEU). This process must include a thorough

inspection of all sides of the mailpiece for evidence of hazardous

materials (e.g., markings). At retail units, mailers must be asked the

question: “Do any of your articles contain anything liquid, fragile,

perishable, or potentially hazardous, such as lithium batteries,

perfume, mercury or aerosols?”

b. If the contents are mailable, determine the specific quantity limitations,

labeling, and packaging requirements that apply.

c. With the exception of destination-entered mail entered at a destination

delivery unit (DDU), destination sectional center facility (DSCF), or

destination network distribution center (DNDC), verify that all

mailpieces containing mailable hazardous materials are presented

separately from mailpieces not containing hazardous materials.

d. Refuse (as permitted in POM 139) to accept material that does not

meet the applicable requirements for mailing and refer the

circumstances to the local postmaster or PCSC for a mailability ruling

under

213 or 215, as appropriate.

e. If a mailpiece containing a diagnostic (clinical) specimen is in a sack or

tub, PS Tag 44 must be attached to ensure that the sack or tub will be

emptied at the processing point.

f. With the exception of destination-entered mail entered at a DDU,

DSCF, or DNDC, ensure mailpieces containing hazardous materials

remain separated from other mailpieces and are placed into labeled

containers further separated by transportation type. See

327.1a and

327.1b.

g. See 253 for guidance regarding hazardous materials found in lobby

drops or retail collection boxes.

252 Hazardous, Restricted, and Perishable Mail

20 Publication 52

See Chapter 7 for guidelines Postal Service acceptance personnel must

follow when handling hazardous materials, restricted matter, or perishable

matter to be transported by air.

252 Guidelines for Dispatch Personnel

The following guidelines for Postal Service dispatch personnel are general in

nature. Specific dispatch procedures for Postal Service operational

employees are in the POM and applicable to the class and content of the

mailpiece.

a. Make sure that the hazardous material, restricted matter, or perishable

matter is given proper handling to avoid damage or danger.

b. Ensure that all mailpieces with a hazardous-materials mark or label are

separated from all other mail and are placed into labeled containers

further separated by transportation type. See

327.1a and 327.1b.

c. Tender to the air carrier only those mailpieces that are properly

packaged and marked. Before a shipment is tendered to a carrier,

make sure that:

(1) A proper and strong packaging method is used.

(2) A secure method of package closure is used, and there is no

visual evidence of leakage or damage. (If damage is detected,

isolate the damaged mailpiece and notify the appropriate

personnel in case of accident or incident and for proper spill

response.)

(3) The outer packaging bears all required markings and/or labels.

(4) A properly completed shipping paper is attached to the outside of

the mailpiece and to the dispatch document. The shipping paper

must include the information detailed in

326 and Exhibit 326.

(5) If the mailpiece contains a material believed to be nonmailable,

remove it from the mailstream and treat it in accordance with

POM 139.117-118, as appropriate.

See Chapter 7 for more information regarding the air transportation of

mailable hazardous materials, restricted matter, or perishable matter.

253 Guidelines for Delivery and Collection Personnel

Delivery and collection personnel must follow these procedures when

delivering and collecting mail:

a. Conduct a thorough examination of all sides of the mailpiece for

hazardous-material labels and markings or any nonmailable hazardous

characteristics (e.g., prohibited marks or labels). If the mailpiece is

nonmailable, leaking, or stained, do not collect it; notify the customer if

present, and contact the supervisor.

b. Ensure that mailable hazardous materials are separated from all other

mail.

September 7, 2023 21

3 Hazardous Materials

31 Definition

A hazardous material is any article or substance designated by the U.S.

Department of Transportation as being capable of posing an unreasonable

risk to health, safety, or property during transportation. In international

commerce, hazardous materials are known as “dangerous goods.” For

definitions of other terms that relate to hazardous materials, see Appendix

32 General

321 U.S. Department of Transportation

The U.S. Department of Transportation (DOT) is the federal agency

responsible for regulating the carriage of hazardous materials within the

United States via any mode of transportation (e.g., highway, rail, air, water).

The federal regulations of the DOT are codified in Title 49 Code of Federal

Regulations (49 CFR), which contains the DOT’s detailed specifications for

packaging, marking, and labeling hazardous materials. Title 49 CFR also

exempts or establishes other requirements for limited quantities and small

quantities of hazardous materials. USPS mailing standards for hazardous

materials generally adhere to 49 CFR, but also include many additional

limitations and prohibitions.

322 Postal Service

The carriage of U.S. Mail by the Postal Service is regulated by Title 39 Code

of Federal Regulations (39 CFR) and is not subject to the federal regulations

in 49 CFR that apply to commercial carriers. Unlike commercial carriers, the

Postal Service is subject to the restrictions in Title 18 United States

Code 1716 (18 U.S.C. 1716), which prohibits from mailing all matter that is

outwardly or of its own force dangerous to life, health, or property (see

211).

As a result, most hazardous materials are nonmailable.

Accordingly, for legal and safety reasons, although mailing standards for

hazardous materials in this publication closely adhere to 49 CFR, the

standards also include many additional limitations and prohibitions and often

are more restrictive than the requirements of other commercial carriers. For

example, 49 CFR allows commercial shippers to send flammable materials

by air, but the Postal Service prohibits the mailing of all flammable materials

via air transportation.

323 Hazardous, Restricted, and Perishable Mail

22 Publication 52

Postal Service standards generally limit the mailing of hazardous materials to

Limited Quantity surface materials or Limited Quantity air materials as

defined in

332 through 336, that meet USPS quantity limitations and

packaging requirements. This allowance is limited to the following:

a. Toy propellant devices and safety fuses in Division 1.4S, as permitted

341.22.

b. Toxic substances in Division 6.1 that have an LD50 for oral toxicity of

greater than 5 mg/kg but less than 50 mg/kg, as permitted in

346.231.

c. Infectious substances (etiologic agents) and medical wastes in

Division 6.2, as permitted in 346.23.

d. Radioactive materials in Class 7 that fall within the specific activity

limits permitted in

347 and Exhibit 347.22.

e. Lithium batteries, dry ice, and magnetized materials, as permitted in

349.

323 Mailer Responsibility

323.1 General

Full responsibility rests with the mailer to comply with all Postal Service and

non-Postal Service laws and regulations in mailing hazardous material.

Anyone who mails, or causes to be mailed, a nonmailable or improperly

packaged hazardous material may be subject to legal penalties (i.e., fines

and/or imprisonment), including but not limited to those specified in 18

U.S.C. Transporting hazardous materials before entry as U.S. Mail and after

receipt from the Postal Service is subject to DOT regulations.

323.2 Service Type Codes

Mailers tendering to the Postal Service packages containing hazardous

materials must use a unique Service Type Code (STC) for domestic

outbound and return packages that corresponds to the product being

shipped (e.g., Priority Mail, Parcel Select Lightweight, and USPS Ground

Advantage). The STC is required regardless of whether mailpieces are

entered at origin or for destination entry. If purchasing an eligible extra

service, mailers must use the STC indicating the product and extra service.

Extra services permitted with hazardous materials mailings are:

a. Signature Confirmation.

b. Insurance less than or equal to $500.

c. Insurance over $500.

d. Signature Requested for Priority Mail Express.

e. Adult Signature over 21 for Priority Mail Express (tobacco/Electronic

Nicotine Delivery System [ENDS] products).

f. Adult Signature over 21 for Priority Mail (ENDS products).

A list of HAZMAT STCs and ESCs is in Appendix G and Pub 199.

Hazardous Materials 324

September 7, 2023 23

323.3 Extra Service Codes

Mailers tendering to the Postal Service packages containing hazardous

materials must use ESC 857. Mailers may optionally use one of 23 unique

content-specific Extra Service Codes (ESC) for domestic outbound and

return packages that corresponds to the specific category of hazardous

material contained within the mailpiece. If one of the content-specific ESC is

used, then ESC 857 may be omitted when not enough extra-service code

fields are available for the package details. A list of ESCs is in Appendix G

and Publication 199.

Note: While using the content-specific ESC is currently a recommended

practice, the Postal Service may make this requirement mandatory in the

future.

323.4 Additional GS1 DotMatrix (2D) IMpb

Effective January 21, 2024, in addition to including the appropriate STC in

the one-dimensional GS1-128 IMpb barcode on the address label, the Postal

Service requires adding two (2) supplemental GS1-DataMatrix (2D) IMpbs to

domestic shipping labels for mailpieces containing hazardous materials —

one in the address block to the left of the delivery address and one in the

lower right corner of the shipping label. For more information on the GS1-

DataMatrix (2D) IMpbs, see GS1 (2D) information and barcode specifications

https://www.gs1.org/docs/barcodes/GS1_DataMatrix_Guideline.pdf and

https://postalpro.usps.com/shipping/impb/2d-impb-guide.

323.5 Shipping Service File

Mailers shipping hazardous materials domestically utilizing PC Postage, eVS,

USPS Ship, and/or ePostage platforms must incorporate the applicable

Service Type Code (STC) and/or Extra Service Code (ESC) listed in

Appendix

G and Publication 199 and transmit a Shipping Services File (SSF),

using Version 1.7 or higher, or Shipping Partner Event File (SPEF), using

Version 5.0 or higher, to the Postal Service before, or concurrent with

tendering any hazardous materials shipments.

323.6 Legacy Postage and Hard-Copy Postage Statements

Mailers using legacy postage meters or hard-copy postage forms must

present hazardous materials mailings to a Postal Service retail or business

mail entry unit for acceptance.

323.7 USPS-Generated Shipping Labels

At the time of label generation, mailers using a label that USPS generated

(including but not limited to USPS APIs, WebTools, Click-n-Ship, or

Merchant Returns Application) must indicate whether the shipment contains

hazardous materials.

324 Mailability Rulings

For information on how to request a mailability ruling for a specific hazardous

material, follow the procedures outlined in

215.2.

325 Hazardous, Restricted, and Perishable Mail

24 Publication 52

325 DOT Hazardous Materials Warning Labels and

Markings

325.1 General Requirements

All required hazardous materials warning labels and markings must be placed

on the address side of the package. Only in limited situations where sufficient

space does not exist, DOT markings may be placed on a side adjacent to the

address. Markings and labels must not be placed on the bottom of a package or

envelope. Other markings required by the Postal Service or other federal

regulatory agencies also must appear on the address side of any mailpiece

containing hazardous material, restricted matter, or perishable matter. Specific

text markings that are required, must be printed on the address side of the

package.

All DOT hazardous materials warning labels and markings must be:

a. Displayed on the same surface of the package and near the proper

shipping name.

b. Displayed next to each other (within six inches) when more than one

marking or label is required.

c. Printed on or affixed to a background of contrasting color or must have a

dotted or solid line outer boundary.

d. Clearly visible; and not obscured by any mark or attachment.

e. Durable and weather-resistant.

f. Oriented as a diamond (square-on-point).

g. At least 100 mm (3.9 inches) on each side, unless specified in 325.1 and

325.4.

h. Printed with solid line inner border at least 5mm inside and parallel to the

edge, and the border widths must be at least 2 mm.

Limited Quantity or UN3373 markings may be permitted to be displayed at a

reduced size with special authorization from the director, Product Classification

(see

214 for address).

325.2 Nonmailable Warning Labels and Marks

In commerce, packages containing hazardous materials must display the

appropriate DOT hazardous materials warning label and markings. Except as

provided in Exhibit 325.3, any mailpiece bearing or required to bear one of the

labels shown in Exhibit 325.2 under 49 CFR, is prohibited from mailing.

Note: The labels shown in the exhibits are not shown to size. DOT

warning labels must meet the size and color requirements in 49 CFR

§172.407 through 172.446 unless special authorization from the director,

Product Classification, is obtained as outlined in

325.1.

Hazardous Materials 325.2

September 7, 2023 25

Exhibit 325.2

DOT Hazardous Materials Warning Labels: PROHIBITED IN THE MAIL

325.3 Hazardous, Restricted, and Perishable Mail

26 Publication 52

325.3 Mailable Warning Labels

The warning labels shown in Exhibit 325.3a, Exhibit 325.3b, and Exhibit

325.4 may appear only on mailpieces containing mailable hazardous

materials that require use of the label under Postal Service requirements.

Divisio

n 5.1, 5.2, Class 8 and Class 9 labels are only permitted when used in

conjunction with a Limited Quantity air mark.

Exhibit 325.3a

DOT Hazardous Materials Warning Labels: PERMITTED ON MAILABLE

HAZARDOUS MATERIALS

Exhibit 325.3b

DOT Hazardous Material Warning Labels: PERMITTED FOR MAILABLE

LIMITED QUANTITIES ONLY

325.4 Limited Quantity Markings

Unless specified in 221.1 and 325.1, each mailpiece containing a mailable

hazardous material must be plainly and du

rably marked on the address side

with the required shipping name and UN identification numbers.

Requirements for the use of DOT Limited Quantity markings intended for air

and surface transportation are as follows:

a. Marking description: The top and bottom portions of the square-on-

poin

t marking and the border forming the square-on-point marking

must be black and the center must be white or of a suitable contrasting

background. See

Exhibit 325.4.

b. Markings must be durable, leg

ible, and readily visible.

Hazardous Materials 325.5

September 7, 2023 27

c. The border forming the square-on-point marking must be at least 2 mm

(0.

08 inch) in width and the minimum dimension of each side of the

marking must be 100 mm (3.94 inches), unless the package size

requires a reduced size marking of no less than 50 mm (1.97 inches) on

each side.

d. Applying a reduced-size (50mm or 25mm with a DOT Special Permit)

limit

ed quantity mark requires prior written approval from the director

of Product Classification (see

214 for address).

e. For transportation by aircraft, the air Limited Quantity mark must have

he symbol ‘‘Y’’ in black color inside the center of the square-on-point

mark and be clearly visible. Mailpieces intended for transport by air

must also be marked with the proper shipping name and identification

number, and display the appropriate DOT-associated marking when

required for the hazard class shipped in accordance in this publication.

f. For surface transportation, a Limited Quantity ground mark (square-on-

int) is not required to include the proper shipping name and

identification number.

Exhibit 325.4

DOT Hazardous Material Warning Labels: PERMITTED FOR LIMITED

QUANTITY SQUARE-ON-POINT

325.5 Excepted Quantity Labels

Hazardous materials eligible to be shipped under the excepted quantity provision, as

described in 49 CFR 173.4a and 337.2, must be prepared following Packaging Instruc-

tion 10B in Appendix C. Each mailpiece must be

ar a DOT-approved excepted quantity

marking, shown in Exhibit 325.4, under the following conditions:

a. The “*” must be replaced by the primary hazard class, or when

assigned, the division of each of the hazardous materials contained in

the package.

b. The “**” must be replaced by the name of the mail owner or mail

ervice provider if not shown elsewhere on the package.

c. The marking must be located on the address side of the mailpiece, not

less than 3.9 inches (100 mm) by 3.9 inches (100 mm), and must be

durable and clearly visible.

326 Hazardous, Restricted, and Perishable Mail

28 Publication 52

Exhibit 325.5

Excepted Quantity Marking

326 Shipping Papers

A shipping paper is defined as a shipping order, bill of lading, waybill,

manifest, or any other document used to identify a hazardous material being

offered for transport. A shipper’s declaration for dangerous goods (shipping

paper) prepared under 49 CFR 172.200 through 172.205 is required for

certain types of hazardous materials when mailed. A sample form is shown in

Exhibit 326. The shipping paper must be completed and signed in triplicate

by the mailer. It must be affixed to the outside of the mailpiece within an

velope or similar carrier that can be easily opened and resealed to allow

viewing of the document. Shipping papers are required as follows:

a. Air Tr

ansportation. Most mailable hazardous materials must be

accompanied by a shipper’s declaration for dangerous goods

(shipping paper). To determine which mailable hazardous materials

require a shipping paper when sent via air transportation, refer to the

appropriate sections in this chapter and the appropriate Packaging

Instruction in Appendix

b. Sur

face Transportation. Certain mailable hazardous material may

require a properly prepared shipping paper. To determine which

mailable hazardous materials require a shipping paper when sent via

surface transportation, refer to the appropriate sections in this chapter,

and the appropriate Packaging Instruction in Appendix

Neither DOT nor the Postal Service makes blank shipper’s declaration forms

ailable to shippers of hazardous materials. It is the responsibility of the

shipper to obtain forms meeting the format specifications in 49 CFR from

commercial printers, vendors, or internet retailers. The shipper is also

responsible for properly completing the form prior to mailing.

Hazardous Materials 326

September 7, 2023 29

Exhibit 326

Shipper’s Declaration for Dangerous Goods (Sample Form)

327 Hazardous, Restricted, and Perishable Mail

30 Publication 52

327 Transportation Requirements

327.1 General

a. Air Transportation. When eligibility for air transportation is sought,

mailable hazardous materials eligible for air transportation per

subchapter 34 must be sent as Priority Mail Express or Priority Mail.

Mailers must prepare mailpieces to meet all requirements that apply to

air transportation. Mailpieces must be properly packaged and labeled

within DMM requirements and the operator variations of the air carrier.

When required, a shipper’s declaration for dangerous goods must be

affixed to the outside of the mailpiece.

Note: Mailable hazardous materials that are prohibited from air

transportation may not be sent as Priority Mail Express or Priority

Mail.

b. Surface Transportation. All hazardous materials eligible to be sent as

Parcel Select Lightweight or USPS Ground Advantage must be

prepared under the requirements that apply to surface transportation.

A mailpiece containing mailable hazardous materials utilizing Parcel

Select Lightweight or USPS Ground Advantage must not, under any

circumstance, be transported on air transportation, except for items in

327.2g.

327.2 Air Transportation Prohibitions

All mailable hazardous materials sent as Priority Mail Express or Priority Mail

must meet the requirements for air transportation. The following types of

hazardous materials are always prohibited on air transportation regardless of

class of mail:

a. Explosives.

b. Anything susceptible to damage or that can become harmful because

of changes in temperature or atmospheric pressures unless protected

against the effects of such changes.

c. Magnetic material that has a field strength sufficient to cause a

compass deviation at a distance of 7 feet or more from any point on the

outer packaging.

d. Flammable materials (gases, liquids, and solids).

e. Radioactive materials.

f. UN3090 lithium metal batteries (including lithium alloy batteries) and

UN3480 lithium-ion batteries (including lithium polymer batteries).

g. Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new or

refurbished devices) containing or packaged with lithium batteries (see

349.12e). For those ZIP Codes that are air transportation only due to

the absence of ground transportation, a multimodal-transportation

solution may be used to transport used, damaged, or defective

electronic devices containing or packed with lithium batteries. See

Appendix

F for a list of 5-digit ZIP Codes where this exception applies.

h. Materials excluded from air shipment by DOT regulations (49 CFR 100-

185) or of the applicable state (country) or air carrier operator variations.

Hazardous Materials 331

September 7, 2023 31

328 Postal Service Hazardous Materials Table

Appendix A, “Hazardous Materials Table: Postal Service Mailability Guide,”

contains a modified version of the DOT Hazardous Materials Table found in

49 CFR 172.101. Appendix

A lists the hazardous materials from 49 CFR and

identifies eligibility for mailing in the domestic mail via air and surface

transportation. The table can be used to determine the mailability of a

hazardous material if the proper shipping name of the material is known.

When only the UN number is known, Appendix

B, “Numerical Listing of

Proper Shipping Names by Identification (ID) Number,” can be used to locate

a proper shipping name for cross referencing back to Appendix A.

The mailability information in Appendix A is based on the Department of

Transportation requirements in this publication and past Postal Service

mailability rulings. The table does not include specific information for

international mail because almost all hazardous materials are prohibited in

international mail. See Chapter

6 for the specific requirements that apply to

international mail.

329 Presentation of Hazardous-Materials Mailings

With the exception of destination-entered mail entered at a DDU, DSCF, or

DNDC, each mailer of mailable hazardous materials requiring a label or

marking must do the following:

a. Present mailpieces containing hazardous materials separately from any

mailpieces not containing hazardous materials. Where mailpieces are

tendered in containers, pallets, or other mail transport equipment (see

Handbook PO-502, Mail Transport Equipment), hazardous-materials

mailpieces must be presented in a separate receptacle from non-

hazardous-materials mailpieces.

b. Clearly mark an exterior side of all receptacles containing hazardous-

materials mailpieces as “HAZMAT.”

33 Hazard Classes

331 Nine Classes

Every hazardous material is assigned to one of nine hazard classes as

defined in 49 CFR 172.101 and 173. The nine hazard classes are as follows:

a. Class 1: Explosives.

b. Class 2: Gases.

c. Class 3: Flammable and Combustible Liquids.

d. Class 4: Flammable Solids.

e. Class 5: Oxidizing Substances, Organic Peroxides.

f. Class 6: Toxic Substances and Infectious Substances.

g. Class 7: Radioactive Materials.

h. Class 8: Corrosives.

i. Class 9: Miscellaneous Hazardous Materials.

331 Hazardous, Restricted, and Perishable Mail

32 Publication 52

Some of the nine hazard classes are further separated into divisions based

on their physical or chemical properties. For postal purposes,

Exhibit 331

summarizes the mailability of hazardous materials by hazard class.

Exhibit 331

DOT Hazard Classes and Postal Mailability

Class

Name of Hazard Class

(and Division when applicable)

Domestic Mail International

Mail and

APO/FPO/DPO

Mail

Air

Transportation

Surface

Transportation

1 Explosives

Division 1.1: Mass Explosive Hazard Prohibited Prohibited Prohibited

Division 1.2: Projection Hazard Prohibited Prohibited Prohibited

Division 1.3: Fire and/or Minor Blast/

Minor Projection Hazard

Prohibited Prohibited Prohibited

Division 1.4: Minor Explosion Hazard Prohibited Only with prior HQ

approval per 341.2c

Prohibited

Division 1.5: Very Insensitive With Mass

Explosion Hazard

Prohibited Prohibited Prohibited

Division 1.6: Extremely Insensitive; No

Mass Explosion Hazard

Prohibited Prohibited Prohibited

2 Gases

Division 2.1: Flammable Gases Prohibited Only Limited

Quantity Surface

material per 342

Prohibited

Division 2.2: Nonflammable Gases ID8000 material

per 342

Only Limited

Quantity Surface

material per 342

Prohibited

Division 2.3: Toxic Gases Prohibited Prohibited Prohibited

3 Flammable and Combustible Liquids

All Flammable Liquids Prohibited Only Limited

Quantity Surface

material per 343

Prohibited

All Combustible Liquids ID8000 material

per 343

Only Limited

Quantity Surface

material per 343

Prohibited

4 Flammable Solids

Division 4.1: Flammable Solids Prohibited Only Limited

Quantity Surface

material per 344

Prohibited

Division 4.2: Spontaneously Combustible Prohibited Only Limited

Quantity Surface

material per 344

Prohibited

Division 4.3: Dangerous When Wet Prohibited Only Limited

Quantity Surface

material per 344

Prohibited

5 Oxidizing Substances, Organic Peroxides

Hazardous Materials 332

September 7, 2023 33

332 Limited Quantity

A limited quantity of a hazardous material is the maximum amount of a

specific hazardous material exempted from DOT labeling or packaging

requirements in 49 CFR. To be eligible to ship under the DOT Limited

Quantity provision, a hazardous material must list an exception in column 8A

of the Hazardous Materials Table in 49 CFR 172.101. Not every hazardous

material is eligible to be shipped as a limited quantity.

Division 5.1: Oxidizing Substances Only Limited

Quantity Air

material per 345

Only Limited

Quantity Surface

material per 345

Prohibited

Division 5.2: Organic Peroxides Only Limited

Quantity Air

material material

per 345

Only Limited

Quantity Surface

material per 345

Prohibited

6 Toxic Substances and Infectious Substances

Division 6.1: Toxic Substances ID8000 material

per 346; other

poisons as

permitted in

346.231

Only Limited

Quantity Surface

material per 346;

other poisons as

permitted in

346.231

Prohibited

Division 6.2: Infectious Substances Only as permitted

in 346

Only as permitted

in 346

Only First-Class

Package

International

Service with

Registered Mail

service per 622

7 Radioactive Material Prohibited Only per 347 Only First-Class

Package

International

Service with

Registered Mail

service per 622

8 Corrosives (Liquids And Solids) Only Limited

Quantity Air

material per 348

Only Limited

Quantity Surface

material per 348

Prohibited

9 Miscellaneous Hazardous Materials

ID8000 materials, UN3077, UN3082,

UN3334, or UN3335 materials

ID8000 material

and other

materials as

permitted in 349

Only Limited

Quantity Surface

material and other

materials as

permitted in 349

Prohibited,

except for

magnetized

materials per

349 and 622.4

and lithium

batteries per

622.5

Exhibit 331

DOT Hazard Classes and Postal Mailability

Class

Name of Hazard Class

(and Division when applicable)

Domestic Mail International

Mail and

APO/FPO/DPO

Mail

Air

Transportation

Surface

Transportation

333 Hazardous, Restricted, and Perishable Mail

34 Publication 52

Under Postal Service requirements, only certain hazard classes and divisions

may be eligible to ship as a Limited Quantity. A material meeting the eligibility

criteria for shipment as a Limited Quantity material is mailable via ground

(surface) and in some instances air transportation, only if it can be further

reclassified as a Consumer Commodity material. It is the responsibility of the

mailer to know the correct DOT hazard class of a hazardous material before

mailing (see

323). When assistance is needed to determine eligibility for

mailing, the mailer may request a ruling from the PCSC as outlined in 215.

333 Consumer Commodity

Consumer commodity is a hazardous material that is packaged and

distributed in a quantity and form intended or suitable for retail sale and

designed for consumption by individuals for their personal care or household

uses. This term can also include certain drugs or medicines.

Not all hazardous material permitted to be shipped as a Limited Quantity

qualify as a consumer commodity. The Postal Service does not apply the

consumer commodity category to materials intended for air transportation in

Hazard Class 5, Class 8, and portions of Class 9. (see 334). The Consumer

Commodity category is unique to the United States, and its use is prohibited

with international mail.

It is the responsibility of the mailer to know the correct DOT hazard class of a

hazardous material before mailing (see

323).

When assistance is needed to determine eligibility for mailing, the mailer may

request a ruling from the PCSC as outlined in

215.

334 USPS Limited Quantity Air Materials

The USPS Limited Quantity Air classification applies to certain hazardous

materials within Hazard Classes 5, 8, and 9 that are permitted specifically in

the Postal Service for air transport. The Limited Quantity air category and

marking may be used in domestic mail only and is prohibited in international

mail.

It is the responsibility of the mailer to know the correct DOT hazard class of a

hazardous material before mailing (see

323).

When assistance is needed to determine eligibility for mailing, the mailer may

request a ruling from the PCSC as outlined in

215.

335 ID8000 Materials

A miscellaneous hazardous class specific to certain materials within

Classes

2, 3, 6.1, and 9 that can qualify as a mailable consumer commodity

material and are reclassed as ID8000 when intended for air transportation is

permitted for domestic mail, subject to the applicable 49 CFR requirements.

Mailpieces must bear the DOT square-on-point marking including the symbol

“Y,” Identification Number “ID8000,” the proper shipping name “Consumer

Commodity,” and an approved DOT Class 9 hazardous material warning

label.

Hazardous Materials 337.3

September 7, 2023 35

336 USPS Limited Quantity Surface Materials

This category is only applicable for materials that present a limited hazard

during transportation due to their form, quantity, and packaging. It is

intended for surface transportation and is unique to domestic Postal Service

networks. The following applies:

a. Limited Quantity Surface Materials are prohibited in Priority Mail

Express, Priority Mail and all classes of international mail.

b. Placing surface transportation labels or associated text markings on

any air-eligible mail service to circumvent air transportation is

prohibited.

c. These materials generally must also qualify as a consumer commodity

to be permitted in the Postal Service network.

d. This material includes those previously classified as ORM-D (“Other

Regulated Material”). See

332 and Appendix A.

337 Excepted Quantity

337.1 Definition

An excepted quantity is a defined amount of a specific hazardous material,

eligible for transport aboard passenger aircraft, which is not subject to any

DOT requirements (e.g., packaging, marking, labeling, etc.) other than those

in 49 CFR 173.4a. Very few hazardous materials can be shipped under the

excepted quantity provision. Additionally, for Postal Service purposes, Class

1, Class 2, Class 4, Division 6.2, and Class 7 materials are not permitted to

be sent as an excepted quantity. The excepted quantity provision is

applicable to domestic mail only, and its use is prohibited for international

shipments or APO/FPO/DPO mail. The excepted quantity provision can be

used in domestic air or surface transportation (highway, rail, or vessel).

337.2 Mailability

Only materials authorized for transport aboard passenger aircraft in

accordance with 49 CFR 172.101 and appropriately classed within one of the

following hazard classes or divisions may be mailed as an excepted quantity:

a. Class 3, Packing Groups II and III;

b. Division 5.1, Packing Groups II and III;

c. Division 5.2 materials, only when contained in a chemical kit, first aid

kit, or polyester resin kit;

d. Division 6.1, Packing Group III only;

e. Class 8, Packing Groups II and III only, except for UN2803, Gallium and

UN2809, Mercury; and

f. Class 9, except for UN1845, Carbon dioxide, solid, or Dry ice, and

lithium batteries.

337.3 Additional Restrictions

Materials identified in Appendix A as prohibited under column E, USPS

Mailability, are ineligible for mailing under the excepted quantity provision

without regard to their hazard class, division, or packing group.

337.4 Hazardous, Restricted, and Perishable Mail

36 Publication 52

337.4 Quantities

The maximum quantity of hazardous materials in each inner (primary)

packaging is limited to 30 g (1 ounce) or 30 ml (1 ounce) for solids or liquids.

The maximum aggregate quantity of hazardous material in any mailpiece

cannot exceed:

1. For Packing Group II materials and Class 9 materials, 500 g (1.1 lbs.)

for solids or 500 ml (.1 gallon) for liquids.

2. For Packing Group III materials, 1 kg (2.2 lbs.) for solids or 1 liter (0.2

gallon) for liquids.

3. For Division 5.2 materials, 500 g (1.1 lbs.) for solids or 500 ml (.1 gallon)

for liquids.

337.5 Packaging and Marking

Hazardous materials eligible to be shipped under the excepted quantity

provision, as described in 49 CFR 173.4a and 337.2, must be prepared

following Packaging Instruction 10B in Appendix C. Mailers entering

mailpieces under the USPS excepted quantity provision must meet the

requirements for packaging materials, and mailpieces must be in compliance

with the package tests regulations in 49 CFR 173.4a. Each mailpiece must

bear a DOT-approved Excepted Quantity marking (see

221.1 and 325.5). If

applicable, include documentation as provided in 49 CFR § 173.4a.

338 Small Quantity

338.1 Definition

A small quantity is the maximum amount of a specific hazardous material that

when transported by domestic highway and rail transportation is not subject

to any DOT requirements (e.g., packaging, marking, labeling, etc.) other than

those specified in 49 CFR 173.4. Not every hazardous material is eligible to

be shipped as a small quantity. Additionally, for Postal Service purposes,

Class 1, Class 2, Division 6.2, and Class 7 materials are not permitted to be

sent as a small quantity.

The small-quantity provision is applicable to domestic mail only, and its use

is prohibited for international shipments or APO/FPO/DPO mail. The small-

quantity provision must only be used for domestic surface transportation

(highway or rail).

338.2 Mailability

Hazardous materials listed in the following categories are eligible to be sent

in domestic mail under the small-quantity provision, via surface

transportation, only when each primary receptacle is limited to 30 milliliters (1

ounce) or less for liquids and 30 grams (1 ounce) or less for solids, as

applicable:

a. Class 3.

b. Division 4.1.

c. Division 4.2 (Packing Groups II and III only).

d. Division 4.3 (Packing Groups II and III only).

Hazardous Materials 341.1

September 7, 2023 37

e. Division 5.1.

f. Division 5.2.

g. Division 6.1 (Packing Group III only).

h. Class 8.

i. Class 9.

338.3 Additional Restrictions

Materials identified in Appendix A as prohibited in table columns (e),

“Domestic Mail Air,” and (f), “Domestic Mail Surface,” are ineligible for

mailing under the small-quantity provision without regard to their hazard

class, division or packing group.

338.4 Packaging and Marking

Hazardous materials eligible to be shipped under the small-quantity

provision permitted in 49 CFR and 338.2 must be prepared following

Packaging Instruction 10A in Appendix C. Each mailpiece that qualifies to be

sent under the small-quantity provision must be clearly marked on the

address side with the following words: “This package conforms to 49 CFR

173.4 for domestic highway or rail transport only.”

339 Packaging Requirements for Hazardous Materials

339.1 DOT Packing Groups

Hazardous materials in Classes 3, 4, 5, Division 6.1, Class 8 and some

Class

9 substances are assigned to a DOT packing group based on the

degree of danger presented by the material during transport. The packing

group assigned to a hazardous material is listed in column 5 of the

Hazardous Material Table in 49 CFR 172.101 and in column (d) of

Appendix

A. Packaging Group designators are always written in Roman

numerals, for example “PG II.” Packing Group I indicates a great danger,

Packing Group II a medium danger, and Packing Group III a minor danger.

339.2 Postal Service Packaging Instructions

For mailing purposes, the packaging of a mailable hazardous material must

follow the appropriate Packaging Instruction in Appendix

C. The correct

Packaging Instruction to use for a specific hazardous material can be

determined using Appendix

Mailers may not package or combine hazardous materials assigned to

different hazard classes within a single mailpiece unless permitted by Postal

Service standard.

34 Mailability by Hazard Class

341 Explosives (Hazard Class 1)

341.1 Definition

An explosive is any substance or article, including a device, that is designed

to function by explosion (an extremely rapid release of gas and heat) or that,

341.11 Hazardous, Restricted, and Perishable Mail

38 Publication 52

by chemical reaction within itself, is able to function in a similar manner even

if not designed to function by explosion, unless the substance or article is

otherwise classed under the provisions in 49 CFR.

341.11 Class 1 Divisions

Hazard Class 1 has six divisions as follows:

a. Division 1.1 consists of explosives that have a mass explosion hazard.

Examples are black powder, nitroglycerine (desensitized), dynamite,

most types of torpedoes, and mercury fulminate.

b. Division 1.2 consists of explosives that have a projection hazard but

not a mass explosion hazard. Examples are certain types of fireworks,

some types of detonating fuses, and some types of ammunition.

c. Division 1.3 consists of explosives that have a fire hazard and either a

minor blast or minor projection hazard or both, but not a mass

explosion hazard. Examples are sodium picramate, some liquid and

solid propellants, and some rocket motors.

d. Division 1.4 consists of explosives that present a minor blast hazard.

Examples are common fireworks, toy caps, empty primed grenades,

and some small arms ammunition.

e. Division 1.5 consists of very insensitive explosives that have a mass

explosion hazard. Examples are type E blasting agents, some type

blasting agents, and very insensitive explosive substances.

f. Division 1.6 consists of extremely insensitive articles that do not have a

mass explosion hazard.

341.12 Class 1 Compatibility Codes

Each division in Class 1 is further assigned a compatibility group code. The

compatibility code consists of one letter (A–H, J–L, N, or S) that is positioned

after the division number (e.g., 1.1A, 1.2C, 1.4S) and refers to the

transportation and storage controls necessary to prevent potential hazards.

See 49 CFR 173.52 for a more detailed description of the Class 1

compatibility codes.

341.2 Mailability, Packaging, and Marking

Explosives are generally prohibited from mailing under 18 U.S.C. 1716. The

following conditions apply to the mailing of explosives:

a. International Mail. All explosives are prohibited.

b. Domestic Mail via Air Transportation. All explosives are prohibited.

c. Domestic Mail via Surface Transportation. Generally, explosives are

prohibited. The only exceptions are for Division 1.4S toy propellant

devices and safety fuses that have been approved by the director,

Product Classification, USPS Headquarters, Washington, DC, before

mailing as stated in

341. A shipping paper is required.

341.21 Nonmailable Explosives

Nonmailable explosives found in the mailstream must be immediately

reported in accordance with POM 139.117.

Hazardous Materials 341.22

September 7, 2023 39

Nonmailable explosives include, but are not limited to, the following:

a. Common Fireworks. Fireworks are classified as Division 1.1, 1.2, 1.3, or

1.4 explosives depending on the degree of hazard. Fireworks include

roman candles, skyrockets, helicopter-type rockets, cylindrical and

cone fountains, pyrotechnic wheels, illuminating torches, firecrackers,

salutes, and combinations of items that are designed to produce any of

the aforementioned types of effects. All types of fireworks are

prohibited from mailing.

b. Fuses. Fuses are classified as Division 1.3 or 1.4 explosives depending

on the degree of hazard. All types of fuses (except safety fuses as

permitted under

341.22) are prohibited from mailing.

c. Small Arms Ammunition. Ammunition is classified as a Division 1.1, 1.2,

1.3, or 1.4 explosive, depending on the degree of hazard. Ammunition

that is regulated as a Class 1 explosive and designed to be fired from a

pistol, revolver, rifle, or shotgun, as well as associated primers and

blank cartridges (including those designed for tools) and propellant

powder for use in any firearm, is prohibited from mailing.

341.22 Mailable Explosives

The following specific types of explosives may be mailed only when the

applicable conditions are met. Full responsibility rests with the mailer to

comply with Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE)

regulations before mailing.

a. Toy Propellant Devices. The proper shipping name for a toy propellant

device is “model rocket motor” or “igniters.” A toy propellant device

assigned UN0454 or NA0323 and classed as a Division 1.4S explosive

is eligible for mailing in domestic mail via surface transportation only

when prior written permission has been obtained from the director,

Product Classification, USPS Headquarters, Washington, DC. A device

approved for mailing is subject to the following conditions:

(1) Each device must be ignitable by electrical means only; contain

no more than 30 g (1.07 oz) of propellant; and produce less than

80 newton seconds of total impulse with thrust duration not less

than 0.050 second.

(2) Each device must be constructed so that all chemical ingredients

are preloaded into a cylindrical paper or similarly constructed

nonmetallic tube that does not fragment into sharp, hard pieces;

must be designed so that it will not burst under normal

conditions of use; must be incapable of spontaneous ignition

under 500° F; and must not contain any type of explosive or

pyrotechnic warhead other than a small, activation-charge,

parachute-recovery system.

(3) Each mailpiece containing approved devices must be prepared

for mailing following Packaging Instruction 1A in Appendix

C. A

shipper’s declaration for dangerous goods is required.

b. Safety Fuses (UN0105). Safety fuses consist of a core of black powder

over-spun with yarns, waterproofing compounds, and/or tapes. Safety

fuses assigned UN0105 as a Division 1.4S explosive may be mailed in

342 Hazardous, Restricted, and Perishable Mail

40 Publication 52

domestic mail via surface transportation only when prior written

approval has been granted by the director, Product Classification,

USPS Headquarters, Washington, DC. Mailable safety fuses must be

prepared using Packaging Instruction 1B in Appendix

C. A shipper’s

declaration for dangerous goods is required.

Note: “Safety Fuses” are not to be confused with “fusees.” Fusees

are rail and highway distress signals that are nonmailable Class 4

flammable solids.

c. Shotgun Hulls, Empty Casings, Nonmetallic Shotgun Hulls, or Casings

Without Primers. These articles are not classified as explosives or

hazardous materials under 49 CFR and, therefore, are mailable subject

to the applicable mailing rules (see

227).

342 Gases (Hazard Class 2)

342.1 Definition

Hazard Class 2 consists of three divisions:

a. Division 2.1, Flammable Gases. A material that is a gas at 68° F (20° C)

or less and 14.7 psi (101.3 kPa) of pressure. Flammable gases also

include materials that have a boiling point of 68° F (20° C) or less at

14.7 psi (101.3 kPa) and that are ignitable at 14.7 psi (101.3 kPa) when

in a mixture of 13 percent or less by volume with air or that have a

flammable range at 14.7 psi (101.3 kPa) with air of at least 12 percent

regardless of the lower limit. These conditions must be established in

accordance with ASTM E681–85, Standard Test Method for

Concentration Limits of Flammability of Chemicals, or other approved

equivalent method. The flammability of aerosols must be determined

using the tests specified in 49 CFR 173.306(i).

b. Division 2.2, Nonflammable, Nontoxic Gases. A material that does not

meet the definition of Division 2.1 or 2.3 and exerts in its packaging an

absolute pressure of 40.6 psia (280 kPa) or greater at 68° F (20° C).

c. Division 2.3, Toxic Gases. A material that is poisonous by inhalation

and is a gas at 68° F (20° C) or less and a pressure of 14.7 psi (101.3

kPa), or a material that has a boiling point of 68° F (20° C) or less at

14.7 psi (101.3 kPa).

342.2 Mailability

342.21 General

The following conditions apply to the mailing of gases:

a. International Mail. All gases are prohibited.

b. Domestic Mail via Air Transportation. Flammable gases in Division 2.1

and toxic gases in Division 2.3 are prohibited. Nonflammable gases in

Division 2.2 are generally permitted if the material can qualify as a

ID8000 material (see

335) and meet the quantity limitations and

packaging requirements in 342.3 and 342.4.

Hazardous Materials 342.23

September 7, 2023 41

c. Domestic Mail via Surface Transportation. Toxic gases in Division 2.3

are prohibited. Flammable gases in Division 2.1 and nonflammable

gases in Division 2.2 are generally permitted if the material can qualify

as a Limited Quantity surface material and meet the quantity limitations

and packaging requirements in

342.3 and 342.4.

342.22 Nonmailable Gases

When any gas that is nonmailable is discovered in the mailstream, the

procedures in POM 139.117 must be followed if the materials present an

immediate threat to persons or property. The procedures in POM 139.118

are followed when there is no immediate threat to persons or property.

The following are some specific types of nonmailable gases:

a. Cigarette Lighters (NA1057). Generally, lighters charged with fuel and

having an ignition system or any similar heating, lighting, or ignition

device are a Class 3 flammable liquid and are nonmailable. However, if

an approval number is obtained from DOT, consideration for mailing

may be requested from the director, PCSC, under the provisions in

343.25.

b. Oxygen, Refrigerated Liquid. Liquid oxygen (UN1073) is prohibited

from mailing under any circumstances.

c. Fire Extinguishers. Fire extinguishers (UN0275, UN0276, UN0323, or

UN0381) that contain propellant explosives are prohibited from mailing.

Note: See 342.23 for mailable types of fire extinguishers.

d. Toxic Gases. All Division 2.3 toxic gases are prohibited from mailing.

342.23 Mailable Gases

The following are examples of mailable gases:

a. Butane. Butane (UN1011) and Receptacles, small (UN2037) with

butane or butane mixtures are Division 2.1 flammable gases. Butane

gases that qualify as a Limited Quantity surface material are

acceptable only in domestic mail via surface transportation when

properly prepared under

342.3 and Packaging Instruction 2A in

Appendix C.

b. Oxygen, Compressed. Oxygen (UN1072) is a Division 2.2

nonflammable gas and is acceptable in domestic mail only if it can

qualify as a Limited Quantity material. The requirements in

342.3 and

Packaging Instruction 2B in Appendix C must be followed.

c. Propane. Propane is a Division 2.1 flammable gas and is acceptable in

domestic mail via surface transportation only if it can qualify as a

Limited Quantity ground material. The requirements in

342.3 and

Packaging Instruction 2A in Appendix C must be followed. Propane is

nonmailable in domestic mail via air transportation.

d. Fire Extinguishers. Extinguishers that contain a Division 2.2

nonflammable compressed gas and are assigned UN1044 are mailable

if they do not contain methyl bromide gas mixtures and the contents

are held in DOT specification 2P or 2Q containers. Only one

extinguisher per mailpiece is permitted, and the compressed gas

contained within the fire extinguisher must be nonflammable,

342.3 Hazardous, Restricted, and Perishable Mail

42 Publication 52

nonpoisonous, or noncorrosive as required under 49 CFR 173.309(a).

The requirements in Packaging Instruction 2B in Appendix

C must be

followed.

Note: Fire extinguishers assigned UN1774 are mailable as Class 8

corrosives subject to the limitations for corrosives in

348.

e. Empty Compressed Gas Containers. Empty used containers of

compressed gas are mailable subject to the same restrictions that

applied when the container was filled (because residual amounts of the

hazardous material might remain present). Empty, unused (i.e., new)

containers are mailable without restriction.

f. Aerosol Paint Products. Aerosol paint products that are defined as

flammable compressed gases are acceptable in the domestic mail via

surface transportation only if they can qualify as a Limited Quantity

ground material and meet the quantity limitations and applicable

packaging requirements in

342.3 and 342.4.

g. Other Mailable Gases. Materials whose contents are under pressure,

such as carbonated beverages, biological/medical products,

cosmetics, foodstuffs and soaps, electronic tubes, and audible fire

alarm systems (except for any that may contain poisonous gases or

others that may be specifically excluded by 49 CFR 173.306), are

acceptable in the domestic mail as follows:

(1) Carbonated Beverages. These items are not regulated as

hazardous materials and are acceptable without restriction.

Carbonated beverages must be properly packaged under

DMM

601.1-7.

(2) Biological Products or Medical Preparations. A product or

preparation in a nonrefillable metal primary receptacle charged

with a nonflammable solution (containing a biological product or

a medical preparation that heat could deteriorate) may be

accepted for domestic surface mail only, provided the conditions

in Packaging Instruction 2F in Appendix

C are followed.

(3) Foodstuffs and Soaps. These materials are mailable provided the

conditions in Packaging Instruction 2D in Appendix

C are met.

(4) Electronic Tubes. These materials are mailable without restriction

if the volume is 30 cubic inches or less and the tube is charged

with gas to a pressure of 35 psig or less. Such tubes must be

packed in a strong outer container and meet the general

packaging requirements in DMM 601.1-7.

(5) Audible Fire Alarm Systems. An audible fire alarm system

mail via surface transportation provided the conditions in

Packaging Instruction 2E in Appendix

C are followed.

342.3 Packaging

Mailable compressed gases must be packaged to protect valves and fittings

and to ensure integrity of the primary receptacle during transport. Containers

must use recessed valves, screw thread caps, tap closures, or other means

to prevent accidental discharge.

Hazardous Materials 342.4

September 7, 2023 43

The following conditions apply:

a. Nonmetal Containers. A mailable gas is acceptable in an

other-than-metal primary receptacle if the water capacity is 4 fluid

ounces (7.22 cubic inches) or less. Packaging Instruction 2A or 2B, as

applicable, must be followed.

b. Metal Containers. Mailable nonflammable and flammable compressed

gases are acceptable in metal primary receptacles that have a water

capacity up to 33.8 fluid ounces (1 liter or 61.0 cubic inches). The liquid

content of the material and the gas must not completely fill the primary

receptacle at 130° F (55° C). Additionally, the following apply:

(1) A DOT 2P container must be used if the internal pressure is from

140 psig to 160 psig at 130° F (55° C).

(2) A DOT 2Q container must be used if the pressure is from 161

psig to 180 psig at 130° F (55° C).

(3) Packaging Instruction 2A or 2B, as applicable, must be followed.

c. A container with an internal pressure over 180 psig at 130° F (55° C) is

prohibited from mailing.

d. Flammable Gases. A mailable flammable compressed gas is restricted

to 4 fluid ounces in a nonmetal primary receptacle or 33.8 fluid ounces

(1 liter) in a metal primary receptacle per mailpiece Packaging

Instruction 2A must be followed.

e. Nonflammable Gases. A mailable nonflammable gas is permitted in

individual 4 fluid ounce nonmetal primary receptacles or 33.8 fluid

ounce (1 liter) metal primary receptacles. Multiple primary receptacles

may be securely packed within a single, strong outer packaging. Each

mailpiece must not exceed a total weight of 25 pounds. Packaging

Instruction 2B must be followed.

342.4 Marking and Documentation

All labels and text markings must be placed on the address side of the

mailpiece unless specified in

221.1 and 325.1. Parcels containing mailable

gases must be marked as follows:

a. For air transportation, parcels must bear the DOT square-on-point

marking. The top and bottom portions of the square-on-point and the

border forming the square-on-point must be black, and the center

must be white or of a suitable contrasting background. The symbol “Y”

must be black, located in the center of the square-on-point, and clearly

visible. Mailpieces must also be marked with the proper shipping name

“Consumer Commodity” and identification number “ID8000.” Each

mailpiece must also bear an approved DOT Class 9 hazardous material

warning label (see

Exhibit 325.3b). A properly completed shipper’s

declaration for dangerous goods prepared in triplicate must be affixed

to the outside of the mailpiece.

b. For surface transportation, parcels must be plainly and durably marked

on the address side with an approved DOT Limited Quantity marking

(see

325.4). Surface shipments bearing the Limited Quantity ground

marking are not required to include the proper shipping name and

342.5 Hazardous, Restricted, and Perishable Mail

44 Publication 52

identification number. A shipper’s declaration for dangerous goods is

not required for mailable gases sent via surface transportation.

c. Markings must be durable, legible, and readily visible, and must be

applied on at least one side or one end of the outer packaging. The

border forming the square-on-point must be at least 2 mm in width,

and the minimum dimension of each side must be 100 mm, unless the

package size requires a reduced size marking of no less than 50 mm

on each side.

342.5 Mailability Rulings

In addition to the information required in 215.2 and 324, requests for

mailability rulings on gases and products containing compressed gases need

to include the following information:

a. Documentation indicating whether or not the contents are a flammable

mixture when dispersed.

b. The internal pressure within the primary receptacle at 70° F (21° C) and

130° F (55° C).

c. Documentation as to whether or not the liquid contents completely fill

the container at 70° F (21° C) and 130° F (55° C).

d. The bursting strength of the primary receptacle.

e. The capacity of the primary receptacle and the number of primary

receptacles proposed to be packed within a single mailpiece.

f. The design methods intended to prevent accidental discharge of the

contents.

343 Flammable and Combustible Liquids

(Hazard Class 3)

343.1 Definition

The terms used in the standards that apply to Hazard Class 3 are defined as

follows:

a. Flammable Liquid means a liquid that has a flashpoint of not more than

140° F (60° C), or any material in a liquid phase that has a flashpoint at

or above 100° F (38° C).

b. Combustible Liquid means any liquid that does not meet the definition

of any other hazard class and has a flashpoint above 140° F (60° C)

and below 200° F (93° C). A flammable liquid with a flashpoint at or

above 100° F (38° C) that does not meet the definition of any other

hazard class may be reclassified as a combustible liquid per 49 CFR

173.120(b).

Note: A liquid with a flashpoint above 200° F (93° C) is not

regulated as a hazardous material and may be mailed subject to

the general packaging requirements in DMM 601.1-7, provided it

possesses no characteristics of another hazard class.

Hazardous Materials 343.22

September 7, 2023 45

343.2 Mailability and Packaging

343.21 Requirements for Flammable Liquids

The following conditions apply:

a. International Mail. Flammable liquid

is prohibited.

b. D

omestic Mail via Air Transportation. Flammable liquid is prohibited.

c. D

omestic Mail via Surface Transportation. Flammable liquid with a

flashpoint of 20° F (–7° C) or below is prohibited. Other flammable

liquids are permitted if the material qualifies as a Limited Quantity

ground material and meets the criteria in

Exhibit 343.21. A mailable

flammable liquid must be prepared according to Packaging Instruction

3A in Appe

ndix

C, as applicable.

Exhibit 343.21

Flammable Liquids

Flashpoint Mailability

° F (-7° C) or below

Not acceptable for mailing.

Above 20

° F (-7° C)

but not more than 73

° F

(23

° C)

Acceptable (with restrictions) for domestic mail via

surface transportation only. Follow requirements for

Packaging Instruction 3A in Appendix C, as applicable.

Above 73

° F (23° C)

but less than 100

° F

(38

° C)

Acceptable (with restrictions) for domestic mail via

surface transportation only. Follow requirements for

Packaging Instruction 3A in Appendix C, as applicable.

100

° F (38° C) and up

to 140

° F (60° C)

Acceptable (with restrictions) for

domestic mail via

surface transportation only. Follow requirements for

Packaging Instruction 3A or 3B in Appendix C, as

applicable.

Note: If

the flashpoint is between 100° F (38° C)

and 140° F (60° C), the liquid may be eligible to

be reclassed as a combustib

le liquid.

Over 140

° F (60° C)

See combustible liquids in

343.22. Follow

requirements for Packaging Instruction 3B in

Appendix C.

343.22

Requirements for Combustible Liquids

The following conditions apply:

a. International Mail. Combus

tible liquid is prohibited.

b. D

omestic Mail via Air Transportation. Combustible liquid is permitted if

the material can qualify as an ID8000 material (see

335) and meets the

criteria in

Exhibit 343.22. Packaging Instruction 3B in Appendix C must

be followed, as applicable.

c. D

omestic Mail via Surface Transportation. Combustible liquids are

permitted if the material qualifies as a Limited Quantity and a consumer

commodity material, and meets the criteria in

Exhibit 343.22.

Packaging Instruction 3B in Appendix

C must be followed, as

applicable.

Exhibit 343.22

Combustible Liquids

Flashpoint Mailability

Below 100

° F (38° C)

Not a combustible liquid. See flammable l

iquids in

343.21.

100

° F (38° C) but not

more than 140

° F (60° C)

A flammable liquid that may be el

igible to be

reclassified as a combustible liquid under

49 CFR 173.120(b). See

343.1. Acceptable (with

restrictions) in domestic mail via surface

transportation only. Follow requirements for

Packaging Instruction 3B in Appendix C, as

applicable.

Above 140

° F (60° C)

but not more than

200° F (93° C)

Acceptable (with restrictions) for domestic

mail via

air transportation or surface transportation. Follow

requirements for Packaging Instruction 3B in

Appendix C, as applicable.

Above 200°F (93°C) The material is not regulated as a hazardous

mate

rial. Such nonregulated materials must be

properly and securely packaged to prevent leakage

under the general packaging requirements in

DMM 601.3.4.

343.23 Hazardous, Restricted, and Perishable Mail

46 Publication 52

343.23 Nonmailable Flammable and Combustible Liquids

When flammable liquids and combustible liquids that are nonmailable under

343.21 or 343.22 are found in the mailstream, the procedures in POM

139.117 must be followed if the materials present an immediate threat to

person

s or property.

The following materials are nonmailable:

a. All flammable liquids having a flashpoint of 20° F (-7° C) or below are

prohibited from mailing.

b. G

asoline (UN1203) is a flammable liquid that normally has a flashpoint

of -50° F. Gasoline is nonmailable under any circumstances.

c. Acetone (UN1090) normally has a flashpoint of 0° F, Benzene (UN1114)

rmally has a flashpoint of 12° F, and Hexane(s) (UN1208) normally

have flashpoints in the vicinity of -15° F. All are nonmailable unless

diluted with less flammable or nonflammable materials sufficient to

raise the flashpoint to 20° F or higher.

343.24 Mailable Flammable and Combustible Liquids

The following are mailable:

a. Paint o

r a related item (UN1263) classified as a flammable or

combustible liquid is generally acceptable for mailing provided it can

qualify as a Limited Quantity surface material and is sent within the

quantity limitations and packaging requirements stated in

343.21 or

343.22, as applicable. Also see 343.26. Mailpieces must be prepared

following Packaging Instruction 3A

or 3B in Appendix C, as applicable.

b. Latex Paint or a

similar water-based paint product that is not

flammable or combustible is not regulated as a hazardous material,

and therefore is not restricted. Also see

343.26. Mailpieces must be

properly packaged under DMM 601.1-7.

Hazardous Materials 343.24

September 7, 2023 47

c. Canned Heat (Sterno) is a flammable liquid that normally has a

flashpoint from 40° F (4° C) to 80° F (27° C). It is permitted if it can

qualify as a Limited Quantity surface material and is sent within the

quantity limitations and packaging requirements stated in

343.21.

Mailpieces must be prepared following Packaging Instruction 3A in

Appendix

d. Lighter Fluid is a flammable liquid that normally has a flashpoint

between 20° F (-7° C) and 55° F (13° C). It is permitted only in domestic

mail via surface transportation provided the fluid can qualify as a

Limited Quantity surface material and is sent within the quantity

limitations and packaging requirements stated in

343.21. Mailpieces

must be prepared following Packaging Instruction 3A in Appendix C.

e. Diesel Fuel (NA1993) is a combustible liquid that normally has a

flashpoint between 110° F (43° C) and 190° F (88° C). It is acceptable

for mailing provided the fluid can qualify as a Limited Quantity surface

material, and the liquid is sent within the conditions stated in

343.22.

Mailpieces must be prepared following Packaging Instruction 3B in

Appendix

f. Fuel Oil (NA1993) is a flammable liquid that normally has a flashpoint

below 100° F (38° C). The specific flashpoint must be accurately

identified by the mailer before a mailability determination can be made.

Fuel oil is mailable if it can qualify as a Limited Quantity surface

material and is sent within the quantity limitations and packaging

requirements stated in

343.21 or 343.22, as applicable. Mailpieces

must be prepared following Packaging Instruction 3A or 3B in

Appendix

g. Adhesives and Cements (UN1133) that are classified as flammable or

combustible liquids are mailable only if they can qualify as Limited

Quantity surface materials and the applicable conditions in

343.21 or

343.22 are met. Mailpieces must be prepared following Packaging

Instruction 3A or 3B in Appendix C, as applicable.

Note: Some adhesives and cements are extremely toxic and may

be classified as Division 6.1 toxic substances. Division 6.1

materials are mailable only as permitted in

346.21.

h. Cleaning Agents and Solvents that are classified as flammable liquids

are mailable only if they can qualify as Limited Quantity surface

materials, and the applicable conditions in

343.21 can be met.

Mailpieces must be prepared following Packaging Instruction 3A in

Appendix

Note: Some cleaning agents and solvents are extremely toxic or

corrosive and may be classified as either a Division 6.1 toxic

substance or a Class 8 corrosive. Division 6.1 toxic materials and

Class 8 corrosives are permitted only within the conditions of

343.21 and 348.2 respectively.

i. Model Fuel (for glow–plug engines) is a flammable liquid that has a

flashpoint ranging from 65° F to 75° F. It is mailable only if it can qualify

as Limited Quantity surface material, and is sent within the quantity

343.25 Hazardous, Restricted, and Perishable Mail

48 Publication 52

limitations and packaging requirements stated in 343.21. Mailpieces

must be prepared following Packaging Instruction 3A in Appendix C.

j. Waxes and Polishes have a wide range of flashpoints. The flashpoint

and toxicity must be accurately identified by the mailer before

mailability can be determined. Any waxes or polishes that are

flammable or combustible liquids are permitted to be mailed, provided

they can qualify as a Limited Quantity surface material and the

applicable conditions in

343.21 and 343.22 are met. Mailpieces must

be prepared following Packaging Instruction 3A or 3B in Appendix C,

as applicable.

343.25 Lighters

A lighter equipped with an ignition element and containing liquid fuel is

classified as a Class 3 flammable liquid. A lighter containing a flammable gas

is classed as a Division 2.1 flammable gas. A lighter that contains either

flammable liquid or flammable gas is permitted only in the domestic mail via

surface transportation with prior written approval and within these

conditions:

a. The design of the lighter is certified by a lighter testing agency

authorized by the DOT Associate Administrator for Hazardous

Materials Safety, per 49 CFR 173.21(i) and 173.308, and an Approval

Number (LAA****) is issued.

b. The prospective mailer of the lighter submits to the PCSC director a

written request for authorization to mail the lighter, accompanied by a

legible copy of the official DOT notice conveying the approval

described in

343.25a, along with a specimen of the actual lighter, the

packaging materials in which each lighter is to be mailed, and the

number of mailpieces and mailing location; the mailer receives from the

PCSC director a letter approving the requested authorization for

mailing.

c. The packaging must be designed to protect the lighter’s sparking

mechanism from accidental ignition caused by friction or external

pressure during transport. Packaging Instruction 3C in Appendix

must be followed.

d. When the mailpiece is presented for mailing, the address side of the

mailpiece must prominently display the proper shipping name

“Lighter(s)” or “Lighter Refill(s)” followed by the Approval Number

(LAA****) and the marking “Surface Only” or “Surface Mail Only,” and all

preparation and packaging requirements in the PCSC director’s

approval letter must be met. A legible copy of the PCSC director’s

approval letter must be presented at the time of the first mailing at each

Postal Service facility.

e. A shipper’s declaration for dangerous goods is not required.

343.26 Paints, Paint-Related Materials, and Inks

The following definitions apply:

a. Paint (UN1263) is the proper shipping name and description for paint,

lacquer, enamel, stain, shellac, varnish, liquid aluminum, liquid bronze,

liquid gold, liquid wood filler, and liquid lacquer base. Paint-related

Hazardous Materials 343.27

September 7, 2023 49

material (UN1263) is the proper shipping name and description for a

paint-thinning, paint-drying, paint-reducing, or paint-removing

compound. See

343.24a and 343.24b for mailability.

b. Inks are defined as colored liquids used for writing, drawing, etc., and

liquids and pastes used in printing. Printing inks usually are mixtures of

finely divided pigments, such as carbon black suspended in a drying

oil. Inks classified as combustible or flammable liquids are generally

mailable, provided they qualify as Limited Quantity surface material,

and meet the applicable requirements in

343.21 or 343.22. Mailpieces

must be prepared using Packaging Instruction 3A or 3B in Appendix C,

as applicable. The following conditions apply:

(1) Regardless of the size or type of container, the primary

receptacle(s) containing inks must be cushioned with sufficient

absorbent material to take up all liquid contents in case of

leakage.

(2) The primary receptacle(s) and the absorbent cushioning material

must be packed within a sealed, leakproof outer packaging.

(3) Inks that are flammable or combustible liquids must meet the

quantity restrictions, packaging requirements, and air or surface

transportation conditions that apply under

343.2.

Note: Inks that do not possess any hazardous characteristics are

not regulated as hazardous materials and are mailable if properly

prepared under the standards for packaging liquids in

451.3 and

DMM 601.3.4.

343.27 Authorization to Mail Ethanol-Based Flammable Liquids or Solids

Flammable liquids or solids that contain ethyl alcohol are eligible to be

mailed via domestic air transportation only with prior written authorization.

Mailers must submit a letter of request to the director, Product Classification

(see

214 for address). The request must include a list of each specific

product to be mailed under the authorization, an SDS for each product, the

office of mailing, and expected frequency and quantity of mailings.

Approvals are initially provided for the duration of one year. Subsequent

approvals are performance-based and will be extended in one- to three-year

increments.

If approved, the mailer must:

a. Present a copy of their authorization letter from the director, Product

Classification, (to be kept on file at the office of mailing) at the time of

the mailer’s first mailing at any given Postal Service facility. Mailings

not supported by an authorization letter will be refused.

b. For content containing not more than 70% ethyl alcohol by volume,

tender only parcels weighing 25

pounds or less. Each non-glass

primary receptacle must not exceed 16 ounces of flammable liquid or

pound of solids. Each glass primary receptacle must not exceed 8

ounces of flammable liquid or 1/2

pound of solids. Total volume of

flammable material per mailpiece must not exceed 96 ounces for

flammable liquids or 16 pounds for flammable solids.

343.3 Hazardous, Restricted, and Perishable Mail

50 Publication 52

c. For content containing more than 70% ethyl alcohol by volume, tender

only parcels weighing 16 pounds or less. Each primary package

receptacle must not exceed 8 ounces of flammable liquid or 1/2 pound

of solids. Total volume of flammable material per mailpiece must not

exceed 48 ounces for flammable liquids or 8 pounds for flammable

solids.

d. Enter parcels using Priority Mail Express or Priority Mail.

e. Label each parcel on the address side with the mailer’s company name

and return address.

f. Label each parcel on the address side with the marking “Contains Air-

Eligible Ethyl Alcohol — Authorization Number #,” using at least 14-

point type.

g. Ensure that the addressee of each parcel is notified that the addressee

is not authorized to re-mail the contents of the parcel via air

transportation. The mailer must include the following written notice:

“Flammable liquids or solids contained in these packages may be

mailed only by consumers (the addressee) via surface transportation in

accordance with USPS Publication 52, section 343. Full responsibility

rests with the mailer to comply with all postal and nonpostal statutes

and regulations regarding mail. Information regarding postal statutes,

regulations, and mailing requirements is available from your local

Postmaster or district manager, Business Mail Entry, and at the Postal

Service’s mailing standards website, Postal Explorer, at

pe.usps.com.”

h. Comply with the warning and labeling requirements set forth in 21 CFR

700, 701.3, and 740.1 when mailing each parcel.

i. Comply with all quantity, packaging, and marking requirements in

Packaging Instruction 3D in Appendix

343.3 Marking and Documentation

All labels and text markings must be placed on the address side of the

mailpiece unless specified in

221.1 and 325.1. Parcels containing mailable

flammable or combustible liquids must be marked as follows:

a. For air transportation, parcels containing mailable Class 3 materials

must bear the DOT square-on-point marking. The top and bottom

portions of the square-on-point and the border forming the square-on-

point must be black, and the center must be white or of a suitable

contrasting background. The symbol “Y” must be black, located in the

center of the square-on-point, and clearly visible. Mailpieces must also

be marked with the proper shipping name “Consumer Commodity”

and identification number “ID8000.” Each mailpiece must also bear an

approved DOT Class 9 hazardous material warning label (see

Exhibit 325.3b). A properly completed shipper’s declaration for

dangerous goods prepared in triplicate must be affixed to the outside

of the mailpiece.

b. For surface transportation, parcels containing mailable Class 3

materials must be plainly and durably marked on the address side with

an approved DOT Limited Quantity marking (see

Exhibit 325.4).

Surface shipments bearing Limited Quantity ground markings are not

Hazardous Materials 344.2

September 7, 2023 51

required to include the proper shipping name and identification

number. A shipper’s declaration for dangerous goods is not required

for mailable Class 3 materials sent via surface transportation.

c. Markings must be durable, legible, and readily visible, and must be

applied on at least one side or one end of the outer packaging. The

border forming the square-on-point must be at least 2 mm in width,

and the minimum dimension of each side must be 100 mm, unless the

package size requires a reduced size marking of no less than 50 mm

on each side.

d. Lighters containing flammable liquids or gases must be marked as

specified in

343.25.

e. Ethanol-based flammable liquids or solids must be marked as

specified in

343.27 and Appendix C, Packaging Instruction 3D.

344 Flammable Solids (Hazard Class 4)

344.1 Definition

Hazard Class 4 consists of three divisions:

a. Division 4.1, Flammable Solids. Any solid material other than one

classed as an explosive that, under conditions normally incident to

transportation, is likely to cause fires through friction or retained heat

from manufacturing or processing, or that can be ignited readily and,

when ignited, burns so vigorously and persistently as to create a

serious transportation hazard.

b. Division 4.2, Spontaneously Combustible. A liquid or solid pyrophoric

material that even in small amounts and without an external ignition

source can ignite within 5 minutes after coming in contact with air, or a

self-heating material that when in contact with air and without an

energy supply is liable to self heat.

c. Division 4.3, Dangerous When Wet. A material that, by contact with

water, is likely to become spontaneously flammable or to give off

flammable or toxic gas at a rate greater than 1 liter per kilogram of the

material per hour.

Examples of flammable solids include certain metallic hydrides, metallic

sodium and potassium, oily fabrics, processed metals, matches, and

nitrocellulose products.

344.2 Mailability

The following conditions apply:

a. International Mail. All flammable solids are prohibited.

b. Domestic Mail via Air Transportation. All flammable solids are

prohibited.

c. Domestic Mail via Surface Transportation. Flammable solids that can

qualify as a Limited Quantity surface material are permitted.

344.21 Hazardous, Restricted, and Perishable Mail

52 Publication 52

344.21 Nonmailable Flammable Solids

When flammable solids that are nonmailable under 344 are found in the

mailstream, the procedures in POM 139.117 must be followed if the

materials present an immediate threat to persons or property.

Strike-anywhere matches are nonmailable in international mail and domestic

mail. Safety matches (book, card, or strike-on-box) are nonmailable in

international and domestic mail via air transportation.

344.22 Mailable Flammable Solids

The following are mailable:

a. Flammable solids that qualify as Limited Quantity surface materials are

permitted in the domestic mail via surface transportation.

b. Safety matches (book, card, or strike-on-box) are permitted only in

domestic mail via surface transportation.

344.3 Packaging, Marking, and Documentation

All labels and text markings must be placed on the address side of the

mailpiece unless specified in

221.1 and 325.1. The following conditions

apply:

a. Mailable Flammable Solids. The conditions in Packaging Instruction 4A

in Appendix C must be followed. Mailpieces containing mailable Class

4 materials must be plainly and durably marked on the address side

with an approved DOT Limited Quantity ground marking (see

325.4).

Shipments bearing the Limited Quantity surface marking are not

required to be marked with the proper shipping name and identification

number. A shipper’s declaration for dangerous goods is not required

for mailable Class 4 materials sent via surface transportation.

b. Safety Matches. The conditions in Packaging Instruction 4B in

Appendix

C must be followed. Mailpieces must be plainly and durable

marked on the address side with “Surface Only” or “Surface Mail Only”

and, as applicable, “Book Matches,” “Strike-on-Card Matches,” or

“Card Matches.” A shipper’s declaration for dangerous goods is not

required.

345 Oxidizing Substances, Organic Peroxides

(Hazard Class 5)

345.1 Definition

Hazard Class 5 consists of two divisions:

a. Division 5.1, Oxidizing Substances. A material that may, generally by

yielding oxygen, cause or enhance the combustion of other materials.

b. Division 5.2, Organic Peroxides. Any organic compound that contains

oxygen in the bivalent structure and that may be considered a

derivative of hydrogen peroxide, where one or more of the hydrogen

atoms have been replaced by organic radicals.

Hazardous Materials 345.3

September 7, 2023 53

Examples of Class 5 materials (not all of which are mailable) include ferric

nitrate, hydrogen peroxide, lead perchlorate, lithium nitrate, organic peroxide

solids or liquids, and some swimming-pool chemicals.

345.2 Mailability

The following conditions apply:

a. International Mail. All oxidizing substances and organic peroxides are

prohibited.

b. Domestic Mail via Air or Surface Transportation. An oxidizing

substance or an organic peroxide that can qualify as Limited Quantity

air or Limited Quantity surface is permitted.

345.21 Nonmailable Class 5 Materials

When nonmailable Class 5 materials are found in the mailstream, the

procedures in POM 139.117 must be followed if the materials present an

immediate threat to persons or property. The procedures in POM 139.118

are followed when there is no immediate threat to persons or property.

The following Class 5 materials are nonmailable:

a. Division 5.1, Oxidizing Substances.

(1) Chlorine dioxide hydrate, frozen.

(2) Hydrogen peroxide solution (more than 20 percent).

(3) Perchloric acid.

(4) Potassium peroxide.

(5) Sodium chlorite.

(6) Tetranitromethane.

(7) Zinc ammonium nitrate.

b. Division 5.2, Organic Peroxides. Organic peroxides are nonmailable

unless they can qualify as Limited Quantity air or Limited Quantity

surface.

345.22 Mailable Class 5 Materials

The following Class 5 materials are mailable:

a. A division 5.1 or 5.2 material that can be reclassified as a Limited

Quantity air or Limited Quantity surface are mailable within the

requirements in

345.2b.

b. Hydrogen Peroxide. There are no restrictions on Division 5.1 hydrogen

peroxide solutions with 8 percent or less hydrogen peroxide content.

Solutions of hydrogen peroxide more than 8 percent but no more than

20 percent are permitted if they can qualify as Limited Quantity air or

Limited Quantity surface.

345.3 Packaging, Marking, and Documentation

All labels and text markings must be placed on the address side of the

mailpiece unless specified in

221.1 and 325.1. Parcels containing mailable

oxidizing substances or organic peroxides must be marked as follows:

a. All mailable Division 5.1 and 5.2 materials must be prepared following

the conditions for Packaging Instruction 5A in Appendix

346 Hazardous, Restricted, and Perishable Mail

54 Publication 52

b. For air transportation, parcels containing mailable Division 5.1 or 5.2

materials must bear the DOT square-on-point marking. The top and

bottom portions of the square-on-point and the border forming the

square-on-point must be black, and the center must be white or of a

suitable contrasting background. The symbol “Y” must be black,

located in the center of the square-on-point, and clearly visible.

Mailpieces must also be marked with the proper shipping name and

identification number. Each mailpiece must also bear an approved DOT

Class 5.1 or 5.2 hazardous material warning label (see

Exhibit 325.3b).

A properly completed shipper’s declaration for dangerous goods

prepared in triplicate must be affixed to the outside of the mailpiece.

c. For surface transportation, parcels containing mailable Division 5.1 or

5.2 materials must be plainly and durably marked on the address side

with an approved DOT Limited Quantity surface marking (see

325.4).

Shipments bearing the Limited Quantity surface marking are not

required to include the shipping name and identification number. A

shipper’s declaration for dangerous goods is not required for mailable

Division 5.1 or 5.2 materials sent via surface transportation.

d. When DOT square-on-point markings are used, markings must be

durable, legible, and readily visible, and must be applied on at least

one side or one end of the outer packaging. The border forming the

square-on-point must be at least 2 mm in width, and the minimum

dimension of each side must be 100 mm, unless the package size

requires a reduced size marking of no less than 50 mm on each side.

346 Toxic Substances and Infectious Substances

(Hazard Class 6)

346.1 Definitions

Hazard Class 6 consists of two divisions:

a. Division 6.1 includes toxic substances, poisons, and irritating material.

Examples of Division 6.1 materials (not all of which are mailable)

include bromobenzyl cyanide, methyl bromide, motor fuel anti-knock

mixtures, and tear gas.

b. Division 6.2 includes infectious substances. Examples of Division 6.2

materials include infectious substances, biological products, regulated

medical waste, sharps medical waste, used health care products, and

forensic materials.

346.11 Division 6.1

The following terms are used in the standards for Division 6.1 materials:

a. Toxic Substance is a poisonous material, other than a gas, that is

known to be so toxic to humans as to cause death, injury, or harm to

human health if swallowed, inhaled, or brought into contact with skin.

b. Oral Toxicity refers to a liquid or solid with a lethal dose (LD

) for acute

oral toxicity of not more than 300 mg/kg that, when administered by

mouth, is likely to cause death within 14 days in half of the test animals.

Hazardous Materials 346.12

September 7, 2023 55

c. Dermal Toxicity refers to a material with an LD

for acute dermal

toxicity of not more than 1,000 mg/kg that, when administered by

continuous contact with bare skin, is likely to cause death within 14

days in half of the test animals.

d. Inhalation Toxicity applies to a dust or mist with a lethal concentration

(LC

) for acute inhalation toxicity of not more than 4 mg/L, or a

saturated vapor concentration in air at 68° F (20° C) greater than or

equal to more than one-fifth of the LC

for acute toxicity on inhalation

of vapors and with an LC

for acute inhalation toxicity of vapors of not

more than 5,000 ml/m

that, when administered by continuous

inhalation for 1 hour, is likely to cause death within 14 days in half of

the test animals.

e. Irritating Material is any liquid or solid substance (such as tear gas) that

gives off intense fumes and causes extreme but reversible localized

irritant effects on the eyes, nose, and throat, temporarily impairing a

person’s ability to function.

346.12 Division 6.2, Infectious Substances

Division 6.2 materials include infectious substances, biological products,

regulated medical waste, sharps medical waste, used health care products,

and forensic materials. Division 6.2 materials are not permitted in

international mail or domestic mail, except when they are intended for

medical or veterinary use, research, or laboratory certification related to the

public health; and only when such materials are properly prepared for mailing

to withstand shocks, pressure changes, and other conditions related to

ordinary handling in transit. Unless otherwise noted, all mailable Division 6.2

materials must meet the mail preparation requirements for air transportation.

The following terms are used in the standards for Division 6.2 materials:

a. Infectious substance means a material known or reasonably expected

to contain a pathogen. A pathogen is a microorganism that can cause

disease in humans or animals. Examples of pathogens include

bacteria, viruses, fungi, and other infectious agents. An infectious

substance must be assigned to one of the following two packaging

categories:

(1) Category A: An infectious substance transported in a form

capable of causing permanent disability or life-threatening or

fatal disease in otherwise healthy humans or animals when

exposure occurs. Category A infectious substances are

nonmailable. A Category A infectious substance is assigned the

identification number UN2814 or UN2900, based on the known

medical history or symptoms of the source patient or animal,

endemic local conditions, or professional judgment concerning

the individual circumstances of the source human or animal.

(2) Category B: An infectious substance that does not meet the

criteria for inclusion in Category A. A mailpiece known or

suspected to contain a Category B infectious substance must

bear the proper shipping name “Biological Substance,

Other Than the Postal

Service (If Different

From Destination

Facility)

a. Name.

b. Complete address (not a Post Office box).

c. Printed or typewritten name of transporter

or intermediate handler.

d. Signature of transporter or intermediate handler and

date signed.

6. Serialized Waste

Shipping Papers

Each waste shipping paper or mail disposal service shipping record must be

serialized using a unique numbering system for identification purposes.

7. Comment Area Each shipping paper must contain an area designated for entering comments or

noting discrepancies.

8. Completion and

stribution of Waste

Shipping Paper

Each shipping paper must contain instructions for properly completing the four-

part form. Copies of the form must be distributed as follows:

a. One copy must be kept by generator (mailer).

b. One copy must be kept by transporter

or intermediate handler for 90 days.

c. One copy must be kept by destin

ation facility for 90 days.

d. One copy must be mailed to gen

erator by destination facility.

9. Emergency Telephone

Number

Each shipping paper must bear the following statement with appropriate

information:

“IN CASE OF EMERGENCY, OR THE DISCOVERY O

F DAMAGE OR LEAKAGE,

CALL 1-800-###-####.”

346.322 Hazardous, Restricted, and Perishable Mail

68 Publication 52

Hazardous Materials 346.322

September 7, 2023 69

d. Package Testing. Vendors must submit to the director, Product

Classification, (see

214 for address) package-testing results from an

independent testing facility for each package for which the vendor is

requesting authorization. In addition, vendors must submit package

testing results from an independent testing facility when the design of a

container system changes or every 24 months, whichever occurs first.

The test results must show that, if every mailpiece prepared for mailing

were subject to the environmental and test conditions in 49 CFR and

the additional test requirements in

346.322e, no contents would be

released into the environment and the effectiveness of the packaging

would not be significantly reduced. The Postal Service may require

proof of accreditation or other documentation to support the

credentials of an independent testing facility.

Packages tested for approval as medical professional packages may

not be tested using pre-primary containers that are currently or have

previously been approved as Postal Service primary containers. In

addition, test reports must identify by brand name the pre-primary

containers that were used during testing.

e. Testing Criteria. Each mailpiece must pass each of the tests described

below:

(1) Leakproof Test. The test must be conducted on one primary

receptacle with the lid in place, without the secondary and outer

packaging. The test duration must be at least 5 minutes and

must be conducted at 20 kPa (3 psi). The pass/fail criterion is as

follows: no air leakage from anywhere other than the closure of

the primary receptacle. Air leakage at the closure is not

considered a failure if the primary receptacle passes the test for

watertightness as determined by placing 50 ml of deionized

water into the primary receptacle, securing the closure, and then

turning the container on its side and observing for any evidence

of leakage. Any evidence of water leaking from the primary

receptacle is a failure.

(2) Stacking Test. One mailpiece must withstand the test in 49 CFR

178.606. The dynamic compression test must be conducted on

the empty, unsealed mailpiece assembled for mailing, without

the primary receptacle(s). The test mass is the vendor-identified

maximum weight, not to exceed 25 pounds, as indicated on the

outer shipping container and on the assembly and closing

instructions. A compensation factor of 1.5 must be used to

compute the test load, based on the vendor-identified weight.

The pass/fail criteria are as follows: no buckling of the sidewalls

sufficient to cause damage to the contents in the primary

receptacle, and in no case does the deflection exceed 1

inch.

(3) Vibration Test. One mailpiece filled with sharps or other regulated

medical waste must withstand the test in 49 CFR 178.608. The

test mailpiece is filled with sharps or other regulated medical

waste to the vendor-identified maximum weight, not to exceed

25 pounds, as indicated on the outer shipping container and on

346.322 Hazardous, Restricted, and Perishable Mail

70 Publication 52

the assembly and closing instructions. The test sample is

prepared as it would be for mailing. The pass/fail criterion is as

follows: no rupture, cracking, or splitting of any primary

receptacle.

(4) Wet Drop Test. Five mailpieces filled with sharps or other

regulated medical waste must withstand the test in 49 CFR

178.609e. Each test mailpiece is filled with sharps or other

regulated medical waste to the vendor-identified maximum

weight, not to exceed 25 pounds, as indicated on the outer

shipping container and on the assembly and closing instructions

included with each mailpiece. Each mailpiece is prepared as it

would be for mailing and subjected to a water spray as described

in the test. A separate, untested mailpiece is used for each drop

orientation: top, longest side, shortest side, and corner. The

pass/fail criteria are as follows: no rupture, cracking, or splitting

of any primary receptacle, and no contents may penetrate into or

through the body or lid of any primary receptacle.

(5) Cold Drop Test. Five mailpieces filled with sharps or other

regulated medical waste must withstand the test in

49 CFR 178.609f. Each test mailpiece is filled with sharps or

other regulated medical waste to the vendor-identified maximum

weight, not to exceed 25 pounds, as indicated on the outer

shipping container and on the assembly and closing instructions

included with each mailpiece. Each mailpiece is prepared as it

would be for mailing and chilled as described in the test. A

separate, untested mailpiece is used for each drop orientation:

top, longest side, shortest side, and corner. The pass/fail criteria

are as follows: no rupture, cracking, or splitting of any primary

receptacle, and no contents may penetrate into or through the

body or lid of any primary receptacle.

(6) Impact Test. One mailpiece filled with sharps or other regulated

medical waste must withstand the test in 49 CFR 178.609h. The test

mailpiece is filled with sharps or other regulated medical waste to

the vendor-identified maximum weight, not to exceed 25 pounds, as

indicated on the outer shipping container and on the assembly and

closing instructions included with each mailpiece. The mailpiece is

prepared as it would be for mailing. The pass/fail criteria are as

follows: no rupture, cracking, or splitting of any primary receptacle,

and no contents may penetrate into or through the body or lid of any

primary receptacle.

(7) Puncture-Resistant Test. Package testing results must show that,

during all of the previous tests, the contents did not penetrate

through the primary receptacle.

(8) Temperature Test. Package testing results must show that each

primary receptacle maintained its integrity when exposed to

temperatures as low as 0°F and as high as 120°F (–18°C to 49°C).

Hazardous Materials 346.323

September 7, 2023 71

(9) Absorbency Test. Package testing results must show that the

primary receptacle(s) contain enough absorbent material to

absorb three times the total liquid allowed within the primary

receptacle in case of leakage. Absorbency is determined by

pouring 150 ml of deionized water into the primary receptacle(s),

then turning the receptacle(s) upside down and observing for any

evidence of free liquid not absorbed on contact. Any evidence of

free liquid is a failure.

(10) Watertight Test. Package testing results must show that no

leakage occurred when 50 ml of deionized water was placed into

the secondary containment system and the entire system was

turned upside down for 5 minutes.

f. Suspension of Authorization. The Postal Service may suspend a

vendor’s authorization based on information that a mailpiece no longer

meets the standards for mailing sharps medical waste and regulated

medical waste containers, or that the mailpiece poses an unreasonable

safety risk to Postal Service employees or the public. The suspension

can be made immediately, making the mailpiece nonmailable

immediately. The vendor may contest a decision to suspend

authorization by writing to the director, Product Classification, (see

214

for address) within 7 days from the date of the letter of suspension. The

appeal should provide evidence demonstrating why the decision

should be reconsidered. Any order suspending authorization remains in

effect during an appeal or other challenge. When a vendor is notified

that its authorization to mail sharps or other regulated medical waste

containers has been suspended, the vendor must immediately do the

following:

(1) Recall all identified containers.

(2) Notify all customers that they cannot mail the identified containers.

(3) Suspend sales and distribution of all identified containers.

(4) Collect the identified containers from distributors, consumers,

and the Postal Service without using the mail and in accordance

with all federal and state regulations.

346.323 Used Health Care Products

Note: See Packaging Instruction 6E in Appendix C.

A used health care product known or reasonably suspected to contain a

Category A material is nonmailable. A used health care product not

suspected to contain an infectious material, or that is known or suspected to

contain a Category B infectious substance and is being returned to the

manufacturer or manufacturer’s designee, is mailable with Priority Mail or

Priority Mail Express service subject to the following packaging

requirements:

a. Each used health care product must be drained of liquid to the extent

possible and placed in a watertight primary receptacle designed and

constructed to ensure that it remains intact under normal conditions of

transport. For a used health care product capable of cutting or

penetrating skin or packaging material, the primary receptacle must be

346.324 Hazardous, Restricted, and Perishable Mail

72 Publication 52

capable of retaining the product without puncture of the packaging

under normal conditions of transport. The primary receptacle must be

marked with the international biohazard symbol shown in

Exhibit 346.321.

b. Each primary receptacle must be placed inside a watertight secondary

container designed and constructed to ensure that it remains intact

under normal conditions of transport. The secondary container must

also be marked with the international biohazard symbol shown in

Exhibit 346.321.

c. The secondary container must be placed inside an outer shipping

container with sufficient cushioning material to prevent movement

between the secondary container and the outer shipping container. An

itemized list of the contents of the primary receptacle and information

concerning possible contamination with a Division 6.2 material,

including its possible location on the product, must be placed between

the secondary container and the outer shipping container. A shipping

paper and a content marking on the outer shipping container are not

required.

346.324 Forensic Material in Category B

Note: See Packaging Instruction 6F in Appendix C.

Forensic material containing a biological material, such as tissue, body fluid,

excreta, or secreta, and sent on behalf of a federal, state, local, or Indian

tribal government agency must be packaged under

346.325 when it is not

known or suspected to contain a Category A or Category B infectious

substance. Forensic material known or suspected to contain a Category A

infectious substance is nonmailable. Forensic material known or suspected

to contain a Category B infectious substance as identified in

346.321 is

mailable utilizing Priority Mail or Priority Mail Express service when triple-

packaged in a primary receptacle, secondary container, and a rigid outer

shipping container as follows:

a. The forensic material must be held within a securely sealed primary

receptacle. The primary receptacle must be surrounded by sufficient

absorbent material (for liquids) and cushioning material to protect the

primary container from breakage. The absorbent material must be

capable of taking up the entire liquid contents of the primary receptacle

in case of leakage. The primary receptacle must be marked with the

international biohazard symbol shown in

Exhibit 346.321.

b. The primary receptacle and the absorbent and cushioning material

must be enclosed in a watertight and securely sealed secondary

container. The secondary container must also display the international

biohazard symbol shown in

Exhibit 346.321.

c. The secondary container must be firmly and snugly packed within a

strong outer shipping container that is securely sealed. A shipping

paper and a content marking on the outer shipping container are not

required.

Hazardous Materials 346.325

September 7, 2023 73

346.325 Nonregulated Materials

Note: See Packaging Instruction 6G in Appendix C.

Nonregulated materials as defined in 346.234 are not subject to regulation as

hazardous materials, but must be properly packaged when presented for

mailing. Regulated medical waste and sharps medical waste must be

packaged and mailed under

346.322, and used health care products must be

packaged and mailed under 346.323. Exempt human and animal specimens

must be packaged under 346.326. Nonregulated materials must be held

within a securely sealed primary receptacle. The primary receptacle must be

surrounded by sufficient absorbent material (for liquids) and cushioning

material to protect the primary receptacle from breakage. The absorbent

material must be capable of taking up the entire liquid contents of the

primary receptacle in case of leakage. Either the primary receptacle or the

inner packaging must be marked with the international biohazard symbol

shown in

Exhibit 346.321. The primary receptacle and the absorbent and

cushioning material must be snugly enclosed in a rigid outer shipping

container that is securely sealed. A shipping paper and a content marking on

the outer shipping container are not required. Nonregulated material

specimens and biological products are subject to the following packaging

standards:

a. Liquid Patient Specimens and Biological Products. Mailers must

package a liquid nonregulated patient specimen, a forensic specimen,

or a biological product (such as polio vaccine) as follows:

(1) Not exceeding 50 ml. A patient specimen or biological product

consisting of 50 ml or less per mailpiece must be packaged in a

securely sealed primary receptacle. Two or more primary

receptacles whose combined volume does not exceed 50 ml

may be enclosed within a single mailpiece. Sufficient absorbent

material and cushioning material to withstand shock and

pressure changes must surround the primary receptacle(s), or be

otherwise configured to take up the entire liquid contents in case

of leakage. The primary receptacle(s) and the absorbent

cushioning must be enclosed in a secondary container with a

leakproof barrier that can prevent failure of the secondary

container if the primary receptacle(s) should leak during

transport. The secondary container must be securely sealed, and

it may serve as the outer shipping container if it has sufficient

strength to withstand ordinary postal processing. The secondary

container must be marked with the international biohazard

symbol shown in

Exhibit 346.321, except when the secondary

container also serves as the outer shipping container. In that

case, the biohazard symbol must appear on the inner packaging

or on the primary container. A shipping paper and a content

marking on the outer shipping container are not required.

346.326 Hazardous, Restricted, and Perishable Mail

74 Publication 52

(2) Exceeding 50 ml. A liquid patient specimen, forensic material, or

biological product that exceeds 50 ml must be packaged in a

securely sealed primary receptacle. A single primary receptacle

must not contain more than 500 ml of specimen. Two or more

primary receptacles whose combined volume does not exceed

500 ml may be enclosed in a single secondary container.

Sufficient absorbent material and cushioning material to

withstand shock and pressure changes must surround the

primary receptacle(s), or be otherwise configured to take up the

entire liquid contents in case of leakage. The primary

receptacle(s) and the absorbent cushioning must be enclosed in

a secondary container with a leakproof barrier that can prevent

failure of the secondary container if the primary receptacle(s)

should leak during transport. The secondary container cannot

serve as the outer shipping container. The secondary container

must be marked with the international biohazard symbol shown

Exhibit 346.321. The secondary container must be securely

and snugly enclosed in a fiberboard box or container of

equivalent strength that serves as the outer shipping container. A

shipping paper and a content marking on the outer shipping

container are not required.

b. Solid or Dry Specimen. A solid or dry specimen, such as a saliva swab,

blood spot, fecal smear, culture or stock, or forensic material, must be

completely dried before packaging in a mailing container or envelope.

Cushioning material to withstand shock and pressure changes is

required only if the dry specimen is placed in a breakable primary

receptacle. When required, the cushioning material must surround the

primary receptacle. The primary receptacle (and cushioning material, if

required) must be enclosed in a secondary container with a siftproof

barrier that can prevent failure of the secondary container if the primary

receptacle breaks during shipment. The secondary container must be

securely sealed, and it may serve as the outer shipping container if it

has sufficient strength to withstand ordinary postal processing. The

secondary container must be marked with the international biohazard

symbol shown in

Exhibit 346.321, except when the secondary

container also serves as the outer shipping container. In that case, the

biohazard symbol must appear either on the inner packaging or on the

primary receptacle. A shipping paper and a content marking on the

outer shipping container are not required.

346.326 Exempt Human or Animal Specimens

Note: See Packaging Instruction 6H in Appendix C.

Exempt human or animal specimens as defined in 346.12d are not subject to

regulation as hazardous materials but when presented for mailing must be

triple-packaged in leakproof (for liquids) or siftproof (for solids) primary

receptacles. Sufficient cushioning and absorbent materials must surround

each primary receptacle containing liquid. Secondary containers for liquids

must be leakproof. Secondary containers for solids must be siftproof. The

primary and secondary packaging must be enclosed in a rigid outer shipping

container. A single primary receptacle must not contain more than 500 ml of

Hazardous Materials 346.327

September 7, 2023 75

a liquid specimen or 500 grams of a s

olid specimen. Two or more primary

receptacles whose combined volume does not exceed 500 ml (for liquids) or

500 grams (for solids) may be enclosed in a single secondary container. The

secondary container cannot serve as the outer shipping container. The

secondary container must be marked with the international biohazard

symbol shown in

Exhibit 346.321. The secondary container must be securely

and snugly enclosed in a fiberboard box or container of equivalent strength

at serves as the outer shipping container. A shipping paper is not required.

The outer shipping container must be marked on the address side with the

words “Exempt human specimen” or “Exempt animal specimen,” as

appropriate. In addition, at least one surface of the outer packaging must

have a minimum dimension of 3.9 inches by 3.9 inches (100 mm by 100 mm).

346.327 Proper Packaging of Mailable Materials

All mailable materials as identified in 346.212 must be properly packaged.

Exhibit 346.327 lists the specific reverence in 346 under which each type of

mailable material must be packaged.

Exhibit 346.327

Packaging References for Mailable Materials, Infectious Substances

(Hazard Class 6, Division 6.2)

Material Being Mailed

Packaging Standards

1. nm = Nonmailable.

n/a = Not applicable.

Nonregulated Category A Category B

Blood for Transfusion 346.325 nm 346.321

Biological Product

346.32

nm 346.321

Culture or Stock 346.325 nm 346.321

Patient Specimen 346.325 nm 346.321

Exempt Human or Animal

Specimen

346.326 n/a n/a

Forensic Material 346.325 nm 346.324

Regulated Medical Waste 346.322 nm 346.322

Sharps Waste 346.322 nm 346.322

Toxin

2. Toxin means a Division 6.1 material from a plant, animal, or bacterial source. A toxin containing

an infectious substance or a toxin contained in an infectious substance must be classified as

Division 6.2; described as an infectious substance; and assigned to UN2814, UN2900, or

UN3373, as appropriate. A Division 6.1 toxin that can qualify as Limited Quantity surface is

permitted when packaged in accordance with 346.231 or 346.31.

346.31 nm 346.321

Treated Medical Waste 346.325 n/a n/a

Used Health Care Product 346.323 nm 346.323

346.4 Hazardous, Restricted, and Perishable Mail

76 Publication 52

346.4 Damaged Parcels

If a mailpiece containing a Class 6 material is found to be damaged or

leaking during Postal Service handling, the incident must be reported in

accordance with POM 139.117 and 139.118 and Handbook

EL-812,

Hazardous Materials and Spill Response (in Part VII, “Response to Hazardous

Material Incidents and Emergencies,” see the section titled “Hazardous

Materials Incident Reports”), as appropriate. The local Postal Service safety

officer (or designee) must immediately initiate the spill response procedures

in Handbook

EL-812. For spills involving infectious substances (etiologic

agents), the following containment and cleanup steps must also be followed:

a. Wear rubber gloves throughout the spill cleanup procedure.

b. Surround the leaking package with absorbent material.

c. Place the leaking package in another box and seal the box.

d. Place the sealed box in a plastic bag and seal the bag.

e. Flood affected surfaces and rinse rubber gloves with household

chlorine bleach, diluted 1

ounce to 1 gallon of water, and let stand for

minutes. Use caution with the chlorine bleach because it is a mildly

corrosive oxidizer. Wipe surfaces dry with an absorbent material, place

the absorbent material in a plastic bag, and incinerate.

f. Report the damaged parcel to the Centers for Disease Control and

Prevention (CDC) at the telephone number listed in

246.

g. Never dispose of etiologic agents in the trash. Contact the area

environmental compliance specialist for specific information on the

appropriate disposal procedures.

347 Radioactive Materials (Hazard Class 7)

347.1 Definition

Radioactive material is defined in 49 CFR 173.403 as any material containing

radionuclides where both the activity concentration and the total activity in

the consignment exceed the values specified in the table in 49 CFR 173.436

or values derived according to the instructions in 49 CFR 173.433.

347.2 Mailability

The following conditions apply:

a. International Mail. Radioactive material is prohibited in international

mail if required to bear a Class 7 Radioactive White-I, Radioactive

Yellow-II, or Radioactive Yellow-III hazardous materials warning label

(see

Exhibit 325.2). See IMM 135.5 for the specific admissibility

requirements that are applicable to international shipments of

radioactive material. Mailable radioactive materials shipments may be

sent only via First-Class Package International Service with Registered

Mail service. Mailable radioactive materials may not have an activity

content that exceeds one-tenth of the limits in

Exhibit 347.22.

b. Domestic Mail via Air Transportation. All radioactive material is

prohibited in domestic air transportation.

Hazardous Materials 347.22

September 7, 2023 77

c. Domestic Mail via Surface Transportation. Radioactive material is

prohibited if it is required to bear a Class 7 Radioactive White-I,

Radioactive Yellow-II, Radioactive Yellow-III hazardous materials

warning label, or the Fissile label (see

Exhibit 325.2). Mailable

radioactive materials may not have an activity content that exceeds the

limits in

Exhibit 347.22, and must be one of the following materials

(proper shipping names and UN identification numbers in

CFR 172.101):

(1) A radioactive material eligible to be shipped as a limited quantity

under 49 CFR 172.101, Radioactive material, excepted

package — Limited quantity of material, UN2910.

(2) An excepted instrument, article, or device including an

instrument and manufactured article (such as a clock, electronic

tube, or apparatus) or a similar device that has a radioactive

material in gaseous or nondispersible solid form as a component

part, Radioactive material, excepted package — instruments or

articles, UN2911.

(3) An excepted article containing natural uranium or thorium,

including manufactured articles in which the sole radioactive

material is natural or depleted uranium or natural thorium,

Radioactive material, excepted package — articles manufactured

from natural uranium or depleted uranium or natural thorium,

UN2909.

347.21 Nonmailable Radioactive Materials

Any package bearing, or required to bear, one of the Class 7 hazardous

materials warning labels for radioactive materials shown in

Exhibit 325.2 is

nonmailable under any conditions. Report nonmailable materials found in the

mailstream to the appropriate officials in accordance with POM 139.117 and

139.118, as applicable. See 347.5 for emergency procedures.

347.22 Mailable Radioactive Materials

As stated in 347.2, the only categories of radioactive material that are

mailable in international mail or in domestic mail via surface transportation

are those that do not have an activity level exceeding the limits in

Exhibit 347.22 and are eligible under 49 CFR to be shipped as excepted

packages for limited quantities; excepted packages for instruments and

articles; and excepted packages for articles containing natural uranium or

thorium. The mailer must provide accurate documentation of the activity

limits, which must not exceed those specified in

Exhibit 347.22.

347.3 Hazardous, Restricted, and Perishable Mail

78 Publication 52

Exhibit 347.22

Activity Limits for Mailable Instruments, Articles, and Limited Quantity Radioactive Materials

1. For mixture of radionuclides, see 49 CFR 173.433(d).

2. These values also apply to tritium in activated luminous paint and tritium adsorbed on solid carriers.

347.3 Packaging

The following packaging requirements apply:

a. Limited Quantities (49 CFR 173.421). Radioactive materials whose activity

per package does not exceed the limits specified in

Exhibit 347.22 are

excepted from specification packaging, marking, and labeling

requirements. All applicable conditions for Packaging Instruction 7A in

Appendix

C must be met.

b. Instruments and Articles (49 CFR 173.424). Instruments and

manufactured articles (including clocks, electronic tubes, or apparatus)

or similar devices having radioactive materials in gaseous or

nondispersible solid form as a component part (whose activity level

does not exceed the limits specified in

Exhibit 347.22) are excepted

from specification packaging, marking, and labeling requirements. All

applicable conditions for Packaging Instruction 7A in Appendix

C must

be met.

c. Excepted Articles Containing Uranium or Thorium (49 CFR 173.426).

Manufactured articles in which the sole radioactive material is natural

or depleted uranium or natural thorium (whose activity level does not

exceed the limits specified in

Exhibit 347.22) are excepted from

specification packaging, marking, and labeling requirements. All

applicable conditions for Packaging Instruction 7A in Appendix

C must

be met.

Nature of Contents

Instruments and articles

Materials Package

Limits

Limits for Each

Instrument or Article

Package

Limits

Solids:

Special form

-2

-3

Normal form

-2

-3

Liquids:

Tritiated water:

<0.0037 TBq/liter (0.1 Ci/L)

-3

-1

37 TBq (1000 Ci)

0.0037 TBq to 0.037 TBq/L (0.1 Ci to 1.0 Ci/L) 3.7 TBq (100 Ci)

>0.037 TBq/L (1.0 Ci/L) 0.037 TBq (1.0 Ci)

Other Liquids:

-3

-1

-4

Gases:

Tritium2

2 x 10

-2

2 x 10

-1

2 x 10

-2

Special form

-3

-2

-3

Other form

-3

-2

-3

Hazardous Materials 347.5

September 7, 2023 79

d. For mailpieces intended for domestic transportation, the radiation level

at any point on the external surface of the mailpiece must not exceed

0.5 millirem per hour.

347.4 Marking

The outside of the inner receptacle or the outside of the secondary

packaging must be marked “Radioactive.” The address side of the mailpiece

must clearly and prominently display one of the following markings, as

applicable:

a. Mailable Limited Quantity Shipments. “This package conforms to the

conditions and limitations specified in 49 CFR 173.421 for radioactive

material, excepted package—limited quantity of material, UN2910, and

is within Postal Service activity limits for mailing.”

b. Mailable Instruments and Articles. “This package conforms to the

conditions and limitations specified in 49 CFR 173.424 for radioactive

material, excepted package—instruments or articles, UN2911, and is

within Postal Service activity limits for mailing.”

c. Mailable Excepted Articles Containing Uranium or Thorium. “This

package conforms to the conditions and limitations specified in 49

CFR 173.426 for radioactive material, excepted package—articles

manufactured from natural uranium (or natural thorium), UN2909, and

is within Postal Service activity limits for mailing.”

347.5 Emergency Procedures

When a nonmailable package of radioactive material is discovered intact in

the mailstream, the following procedures must be immediately followed:

a. Place the parcel at least 15 feet from other mail or personnel. Under no

circumstances may the package be dispatched.

b. Report the mailpiece to the appropriate officials in accordance with

POM 139.117 and 139.118, as applicable.

c. If a package of radioactive material is damaged or is leaking,

immediately contact the facility safety officer (or designee). The safety

officer will:

 Follow the appropriate spill-response procedures.

 Isolate the area around the damaged package to prevent contact

with people.

 Isolate any conveyor, belt, chute, or other equipment or

conveyance, including mailbags, in which the radioactive

material has leaked or may have leaked.

 Rope off or guard the isolated area whenever practical.

 Place a temporary sign indicating the presence of radioactive

materials and bearing a warning to stay beyond the edge of the

roped area.

347.5 Hazardous, Restricted, and Perishable Mail

80 Publication 52

The local postmaster or facility manager must immediately request the

assistance of qualified persons to check radiation hazards and to

supervise the salvage and decontamination. This assistance may be

received from the mailer (if known) or from one of the following

contacts:

(1) Nearest office of the Department of Energy (DOE) as listed in

Exhibit 347.5c(1) or DOE’s national emergency number and

website are:

DEPARTMENT OF ENERGY (DOE)

EMERGENCY OPERATIONS CENTER

Telephone: 202-586-8100

www.doe.gov

(2) Local health, fire, or police departments.

(3) Local civil defense authorities.

(4) Nearby military installations.

(5) Nearby scientific laboratories.

(6) The Nuclear Regulatory Commission, the Environmental

Protection Agency, and the Federal Emergency Management

Agency, whose national emergency numbers and websites are

as follows:

NUCLEAR REGULATORY COMMISSION (NRC)

Telephone: 301-816-5100

www.nrc.gov

ENVIRONMENTAL PROTECTION AGENCY (EPA)

NATIONAL RESPONSE CENTER

Telephone: 800-424-8802

www.epa.gov

FEDERAL EMERGENCY MANAGEMENT AGENCY (FEMA)

NATIONAL EMERGENCY COORDINATION CENTER

Telephone: 202-646-2400

www.fema.gov

Hazardous Materials 348.2

September 7, 2023 81

Exhibit 347.5c(1)

DOE Regional Coordinating Offices

Department of Energy

Regional Coordinating Offices for

Geographical Areas of Responsibility

Regional Coordinating Office

Telephone for

Assistance Areas Served

1. Brookhaven, NY 631-344-2200 Connecticut, Delaware, Maine, Maryland,

Massachusetts, New

Hampshire, New Jersey, New

York, Pennsylvania, Rhode Island, Vermont

2. Oak Ridge, TN 865-576-1005 Arkansas, Kentucky, Louisiana, Mississippi, Missouri,

Tennessee, Virginia, West Virginia (includes Puerto

Rico and the Virgin Islands)

3. Savannah River, SC 803-725-3333 Alabama, Florida, Georgia, North Carolina, South

Carolina

4. Albuquerque, NM 505-845-4667 Arizona, Kansas, New Mexico, Oklahoma, Texas

5. Chicago, IL 630-252-4800 Illinois, Indiana, Iowa, Michigan, Minnesota, Nebraska,

North Dakota,

Ohio, South Dakota, Wisconsin

6. Idaho Falls, ID 208-526-1515 Colorado, Idaho, Montana, Utah, Wyoming

7. Oakland, CA 925-422-8951 California, Hawaii, Nevada

8. Richland, WA 509-373-3800 Alaska, Oregon, Washington

Headquarters – Washington, DC 202-586-8100

348

Corrosives (Hazard Class 8)

348.1 Definition

A corrosive is any liquid or solid that causes visible destruction or irreversible

alteration in human skin tissue at the site of contact, or a liquid that has a

severe corrosion rate on steel. The term “corrosive” includes all items

commonly referred to as acids, as well as most batteries.

348.2 Mailability

a. International Mail. All corrosives are prohibited.

b. Domes

tic Mail. A corrosive material that qualifies as a Limited Quantity

air or Limited Quantity surface transportation is permissible. Mailable

corrosives are also subject to the following:

(1) A liquid mixture must be 1 pint (16 oz) or less and must contain

5 percent or less corrosive material, with the remainder of the

mixture not being a hazardous material, unless otherwise

specified in

348.22 for a specific corrosive material.

(2) A solid mixture must be 10 pounds

or less per primary receptacle

and must contain 10 percent or less corrosive material, with the

remainder of the mixture not being a hazardous material, unless

otherwise specified for a specific corrosive solid.

348.21 Hazardous, Restricted, and Perishable Mail

82 Publication 52

348.21 Nonmailable Corrosives

Nonmailable corrosives include the following:

a. Batteries (UN2794, UN2795) with liquid electrolyte (such as automobile

lead acid batteries), except for the nonspillable type allowed under

348.22.

b. Nitric Acid (UN2031, UN2032).

c. Fuming and Spent Sulfuric Acids (UN1831, UN1832).

d. Hydrofluoric Acid (UN1790).

e. Mercury (UN2809), and devices containing metallic mercury, such as

thermometers, barometers, and sphygmomanometers (i.e., blood

pressure meters).

348.22 Mailable Corrosives

As a rule, liquid corrosives are limited to 15 percent solution or less as stated

348.2, unless otherwise specified below. Mailable corrosives include the

following:

a. Acetic Acid (UN2790). Acceptable in solutions that can qualify as a

Limited Quantity air material or Limited Quantity surface material,

contains less than 80 percent acid, and does not exceed 1 pint.

Packaging Instruction 8A must be followed.

b. Batteries. Mailable batteries include:

(1) Common household dry-cell batteries such as sizes AA, AAA, C,

D, etc. are generally not regulated as hazardous materials and

are therefore mailable. For nickel-metal hydride batteries in sea

transportation, see 49 CFR 122.102, Special Provision 130.

Packaging requirements in DMM 601.1-7 apply.

(2) A nonspillable wet battery containing liquid electrolyte is

permitted to be mailed only if the battery casing is completely

sealed to prevent the liquid corrosive from spilling during Postal

Service handling. Nonspillable batteries with UN2800 are

prohibited in international mail but may be sent as domestic mail

via air or surface transportation when prepared within the

conditions of Packaging Instruction 8B in Appendix

(3) For lithium and lithium-ion batteries, see 349.22.

c. Hydrochloric Acid (UN1789). Acceptable only in solutions not

exceeding 10 percent acid that can qualify as a Limited Quantity air

material or Limited Quantity surface material. Packaging Instruction 8A

in Appendix

C must be followed.

d. Sulfuric Acid (UN2796). Acceptable only in solutions of 25 percent or

less acid that can qualify as a Limited Quantity air or Limited Quantity

surface material. Packaging Instruction 8A in Appendix

C must be

followed.

e. Dyes (UN2801, UN3147). Acceptable if the dyes can qualify as Limited

Quantity air material or Limited Quantity surface material. Mailable

dyes must be packaged as required in

348.3 and Packaging Instruction

8A in Appendix C.

Hazardous Materials 348.4

September 7, 2023 83

f. Photographic Mixtures. Acceptable if the corrosive liquid solutions for

preparing photographic processing mixtures can qualify as a Limited

Quantity air material or Limited Quantity surface material. Packaging

Instruction 8A in Appendix

C must be followed. When these liquids are

in securely closed and sealed bottles that are properly cushioned, they

may be packed in the same outside shipping container with required

amounts of packaged dry chemicals not classified as hazardous

materials (provided no dangerous reaction would occur should the

contents of the bottles be mixed with the dry chemicals).

g. Manufactured devices that contain small amounts of mercury

(UN3506). Compact Fluorescent Lamps (CFL) and similar consumer

devices containing minute amounts of mercury are mailable by air or

surface only when each device, article, or apparatus contains

100

milligrams (mg) (0.0035 ounce) or less of mercury (less than a grain

of salt) and each mailpiece contains no more than 1 gram (g)

(0.035

ounce) of mercury. Mercury contained in devices categorized

under UN3506 typically exists in a vaporized state — no metallic

mercury will be visible in UN3506 devices. See Packaging Instruction

8C in Appendix

C for mailing details.

348.3 Packaging

Mailable corrosives, both liquids and solids, must meet the applicable

requirements in 348.2b and be prepared as required in Packaging Instruction

8A in Appendix

C, or as permitted in 348.22.

348.4 Marking and Documentation

All labels and text markings must be placed on the address side of the

mailpiece unless specified in

221.1 and 325.1. Parcels containing mailable

corrosive material must be marked as follows:

a. For air transportation, a mailpiece containing a mailable corrosive

material must bear the DOT square-on-point marking. The top and

bottom portions of the square-on-point and the border forming the

square-on-point must be black, and the center must be white or of a

suitable contrasting background. The symbol “Y” must be black,

located in the center of the square-on-point, and clearly visible.

Mailpieces must also bear the appropriate approved DOT Class 8

hazardous material warning label, the identification number, and the

proper shipping name. A properly completed shipper’s declaration for

dangerous goods must be affixed to the outside of the mailpiece.

b. For surface transportation, parcels containing mailable Class 8

materials must be plainly and durably marked on the address side with

an approved DOT Limited Quantity surface mark (see

325.4). Surface

shipments bearing the Limited Quantity surface marking are not

required to include the proper shipping name and identification

number. A shipper’s declaration for dangerous goods is not required

for mailable Class 8 corrosives sent via surface transportation.

c. When the DOT square-on-point markings are used, markings must be

durable, legible, and readily visible, and must be applied on at least

one side or one end of the outer packaging. The border forming the

349 Hazardous, Restricted, and Perishable Mail

84 Publication 52

square-on-point must be at least 2 mm in width, and the minimum

dimension of each side must be 100 mm, unless the package size

requires a reduced size marking of no less than 50 mm on each side.

349 Miscellaneous Hazardous Materials

(Hazard Class 9)

349.1 Definition

A miscellaneous hazardous material is a substance or article that presents a

hazard during transportation, but does not meet the definition of any other

hazard class. Examples of miscellaneous hazardous materials (not all of

which are mailable) include solid dry ice, lithium batteries, magnetized

materials, elevated temperature substances, environmentally hazardous

substances, life-saving appliances (i.e., automobile air–bags, self-inflating life

vests), and asbestos. Miscellaneous hazardous materials include:

a. Any material that has an anesthetic, noxious, or other similar property

that could cause extreme annoyance or discomfort to a flight crew

member.

b. Any elevated temperature material, hazardous substance, hazardous

waste (other than Division 6.2 medical waste), or marine pollutant.

349.11 Lithium Battery — Classifications:

a. Lithium-ion cell or battery means a rechargeable electrochemical cell

or battery in which the positive and negative electrodes are both lithium

compounds constructed with no metallic lithium in either electrode.

These batteries are also referred to as secondary or rechargeable

lithium cells or batteries, and are typically used in cell phones and

laptop computers.

b. Lithium-ion polymer cell or battery means a rechargeable cell or battery

that uses lithium-ion chemistries and is regulated as a lithium-ion cell

or battery.

c. Lithium metal cell or battery means an electrochemical cell or battery

utilizing lithium metal or lithium alloys as the anode. The lithium content

of a lithium metal or lithium alloy cell or battery is measured when the

cell or battery is in an undischarged state. The lithium content of a

lithium metal or lithium alloy battery is the sum of the grams of lithium

content contained in the component cells of the battery. These

batteries are also referred to as primary or nonrechargeable lithium

cells or batteries, and are often used in consumer products such as

cameras and flashlights.

d. Button cell battery means a small single cell round battery with the

overall height less than the diameter. Button cells are used to power

small portable electronic devices such as wrist watches, pocket

calculators, and hearing aids, and are often installed in electronic

devices as auxiliary power sources. For the purposes of mailability as

button cell batteries, lithium metal batteries must contain no more than

0.3 gram of lithium content and lithium-ion batteries must be 2.7 watt-

hours or less.

Hazardous Materials 349.2

September 7, 2023 85

e. Lithium cell means a single encased electrochemical unit with a single

positive electrode (anode) and single negative electrode (cathode),

which exhibits a voltage differential across its terminals. For the

purpose of mailability, marking, and documentation requirements, a

single cell lithium battery is classified as a lithium cell.

f. Lithium battery means one or more lithium cells which are electrically

connected together by a permanent means, including case, terminals,

and markings.

349.12 Lithium Battery — Definitions

a. Equipment means the device or apparatus for which the lithium cells or

batteries will provide electrical power for its operation.

b. Lithium battery consignment means one or more mailpieces containing

lithium batteries, entered into USPS networks by one mailer or mail

service provider within a single mailing or retail transaction, or included

in the same manifest or shipping services file, and intended for delivery

to a single consignee at a single destination address.

c. Short circuit means a direct connection between positive and negative

terminals of a cell or battery that provides an abnormally low resistance

path for current flow.

d. Watt-hour (Wh) means a unit of energy equivalent to one watt (1 W) of

work acting for one hour (1 h) of time. The watt-hour rating of a lithium-

ion cell or battery is determined by multiplying the rated capacity of a

cell or battery in ampere-hours, by its nominal voltage. Therefore, watt-

hour (Wh) = ampere-hour (Ah) x volts (V).

e. Used, damaged, or defective electronic device means an electronic

device containing or packaged with one or more lithium cells or

batteries, and the electronic device:

(1) Is not new in original packaging;

(2) Is not manufacturer-certified new or refurbished; and/or

(3) Has some form of damage or defect.

349.2 Mailability

a. International Mail. All miscellaneous hazardous materials are

prohibited, except for certain magnetized materials as permitted in

349.242a and IMM 136.1g, and small consumer-type lithium batteries

(installed in the equipment they operate) as permitted in 622.5 and IMM

135.6.

b. Domestic Mail. A miscellaneous hazardous material that can qualify as

a mailable air-eligible consumer commodity material (ID8000) when

intended for air transportation, or limited quantity surface material

when intended for surface transportation, is permitted in domestic

mail, subject to the applicable 49 CFR requirements. Only certain

materials within Classes 2, 3, 6.1, and 9 are mailable by air

transportation; mailpieces including eligible quantities of these

materials must be marked with the proper shipping name “Consumer

349.21 Hazardous, Restricted, and Perishable Mail

86 Publication 52

Commodity.” Additionally, lithium batteries, dry ice, and magnetized

materials are permitted within the specified limits provided in

349.221,

349.222, 349.23, and 349.24.

349.21 Nonmailable Class 9 Materials

The following materials are prohibited:

a. All Class 9 materials that cannot qualify as a Limited Quantity air or

Limited Quantity ground material, except for lithium batteries, dry ice,

and magnetized materials.

b. All magnetized materials that have a measurable magnetic field

strength greater than 0.00525 gauss at 15 feet.

c. For air transportation, all magnetized materials that can cause a

compass deviation at a distance of 7 feet or more.

d. In domestic mail via air transportation, dry ice in quantities exceeding

pounds per mailpiece.

e. All lithium batteries in international mail, unless they are within the

specified limits and only when properly installed in the equipment they

operate.

f. All lithium batteries in domestic air transportation, unless they are

within the specified limits and only when properly installed in, or

packed with, the equipment they are intended to operate.

g. Damaged, defective, or recalled batteries unless approved by the

director, Product Classification (see

214 for address).

h. All used, damaged, or defective electronic devices in international mail

or domestic air transportation. This excludes devices that are new in

original packaging, and manufacturer-certified new or refurbished

devices.

349.22 Mailable Class 9 Materials

349.221 Lithium Metal (Nonrechargeable) Cells and Batteries — Domestic

For domestic mailings only, small consumer-type lithium metal cells or

batteries (also called primary lithium cells or batteries) like those used to

power cameras and flashlights are mailable domestically under the following

conditions. See

622 or IMM 136 when mailing batteries internationally or to

APO/FPO/DPO destinations.

a. General. The following restrictions apply to the mailability of all lithium

metal (or lithium alloy) cells and batteries:

(1) Each cell must contain no more than 1.0 gram (g) of lithium

content per cell.

(2) Each battery must contain no more than 2.0 g aggregate lithium

content per battery.

(3) Each cell or battery must meet the requirements of each test in the

UN Manual of Tests and Criteria, part III, and subsection 38.3 as

referenced in DOT’s hazardous materials regulation at 49 CFR 171.7.

(4) All outer packages must have a complete delivery and return

address.

Hazardous Materials 349.221

September 7, 2023 87

(5) All packaging must meet applicable requirements specified in 49

CFR 173.185. Except for mailpieces containing button cell

batteries properly installed in the equipment they are intended to

operate, mailpieces containing lithium metal batteries must be

rigid, sealed, and of adequate size, so the mark can be affixed to

the address side without the mark being folded. The use of

padded and poly bags as outer packaging is permitted only when

the mailpieces contain button cell batteries meeting the

classification criteria in 349.11d, the batteries are properly

installed in the equipment they are intended to operate, and the

batteries are afforded adequate protection by that equipment.

(6) Except for mailpieces containing button cell batteries installed in

equipment (including circuit boards), or no more than 4 lithium

metal cells or 2 lithium metal batteries installed in the equipment

they operate, mailpieces containing lithium metal batteries must

bear a DOT-approved lithium battery mark, as specified in

CFR 173.185(c)(3)(i) and Exhibit 325.2a, applied to the

address side of the mailpiece. Marks must not be applied in such

a manner that parts of the mark appear on different sides of the

mailpiece.

(7) The mark must indicate UN3090 for lithium metal cells or

batteries. UN3091 must be indicated where the lithium cells or

batteries are contained in or packed with the equipment they are

intended to operate. The mark must also include a telephone

number for those who need to obtain additional information.

(8) All used, damaged, or defective lithium metal cells or batteries or

electronic devices contained in or packed with lithium metal cells

or batteries (excluding electronic devices that are new in original

packaging, and manufacturer-certified new or refurbished

devices) must be marked with the text “Restricted Electronic

Device” and “Surface Transportation Only” on the address side

of the mailpiece.

b. Installed in Equipment. The following additional restrictions apply to the

mailing of lithium metal cells or batteries properly installed in the

equipment they operate:

(1) The batteries installed in the equipment must be protected from

damage and short circuit.

(2) The equipment must be equipped with an effective means of

preventing it from being inadvertently turned on or activated.

(3) The equipment must be cushioned to prevent movement or

damage and, unless excepted under 349.221a(5), must be

contained in rigid outer packaging, sealed and strong enough to

prevent crushing of the package or exposure of the contents

during normal handling in the mail.

349.221 Hazardous, Restricted, and Perishable Mail

88 Publication 52

(4) For lithium metal cells and batteries containing no more than 0.3

gram of lithium content, no mailpiece may exceed 2.5 kilograms

(5.5 pounds). There is no maximum number of cells or batteries

per mailpiece.

(5) For lithium metal cells containing more than 0.3 gram but no

more than 1.0 gram of lithium content, and batteries containing

more than 0.3 gram but no more than 2.0 grams of lithium

content, no mailpiece may exceed 5 kilograms (11 pounds). Each

mailpiece may contain a maximum of 8 cells or 2 batteries, with

no more than 1.0 gram of lithium content per cell or 2.0 grams of

lithium content per battery.

(6) When required or optionally applied, mailpieces must display a

DOT-approved lithium battery mark on the address side.

(7) DOT-approved lithium battery markings must be applied to all

mailpieces when there are more than two mailpieces in a single

consignment as defined in 349.12b.

c. Mailed With Equipment. The following additional restrictions apply to

the mailing of lithium metal cells or batteries shipped with (but not

installed in) the device or equipment being mailed:

(1) The shipment cannot contain more batteries than the number

needed to operate the device.

(2) The lithium metal cells and batteries must be packaged

separately and cushioned to prevent movement or damage.

(3) The shipment must be cushioned to prevent movement or

damage, and must be contained in rigid outer packaging, sealed

and strong enough to prevent crushing of the package or

exposure of the contents during normal handling in the mail.

(4) For lithium metal cells and batteries containing no more than 0.3

gram of lithium content, no mailpiece may exceed 2.5 kilograms

(5.5 pounds). There is no maximum number of cells or batteries

per mailpiece.

(5) For lithium metal cells containing more than 0.3 gram but no

more than 1.0 gram of lithium content, and batteries containing

more than 0.3 gram but no more than 2.0 grams of lithium

content, no mailpiece may exceed 5 kilograms (11 pounds). Each

mailpiece may contain a maximum of 8 cells or 2 batteries, with

no more than 1.0 gram of lithium content per cell or 2.0 grams of

lithium content per battery.

(6) Mailpieces must display a DOT-approved lithium battery mark on

the address side.

d. Mailed Without Equipment. The following additional restrictions apply

to the mailing of lithium metal cells or batteries without equipment

(individual batteries):

(1) The lithium metal cells and batteries must be mailed in “the

originally sealed packaging.”

(2) The sealed packages of batteries must be separated and

cushioned to prevent short circuit, movement, or damage.

Hazardous Materials 349.222

September 7, 2023 89

(3) The shipment must be cushioned to prevent movement or

damage, and must be contained in rigid outer packaging, sealed

and strong enough to prevent crushing of the package or

exposure of the contents during normal handling in the mail.

(4) Mailpieces must be sent by surface transportation only.

(5) Mailpieces must display a DOT-approved lithium battery mark on

the address side, in addition to the text “Surface Mail Only,

Primary Lithium Batteries — Forbidden for Transportation Aboard

Passenger Aircraft” or “Surface Mail Only, Lithium Metal

Batteries — Forbidden for Transportation Aboard Passenger

Aircraft.”

(6) The mailpiece must not exceed 5 pounds.

349.222 Lithium-ion (Rechargeable) Cells and Batteries — Domestic

Small consumer-type lithium-ion cells and batteries (also called secondary

lithium cells or batteries) like those used to power cell phones and laptop

computers are only mailable domestically under the following conditions.

See

622 or IMM 135.6 when mailing batteries internationally or to and from

APO/FPO/DPO destinations.

a. General. The following additional restrictions apply to the mailability of

all secondary lithium-ion or lithium polymer cells and batteries:

(1) The watt-hour rating must not exceed 20 Wh per cell.

(2) The watt-hour rating must not exceed 100 Wh per battery.

(3) Each battery must bear the “Watt-hour” or “Wh” marking on the

battery to determine if it is within the limits defined in items

and 2.

(4) Each cell or battery must meet the requirements of each test in the

UN Manual of Tests and Criteria, part III, and subsection 38.3 as

referenced in DOT’s hazardous materials regulation at 49 CFR 171.7.

(5) All outer packages must have a complete delivery and return

address.

(6) All packaging must meet applicable requirements specified in 49

CFR 173.185. Except for mailpieces containing button cell

batteries properly installed in the equipment they are intended to

operate, mailpieces containing lithium-ion batteries must be

rigid, sealed, and of adequate size, so the mark can be affixed to

the address side without the mark being folded. The use of

padded and poly bags as outer packaging is permitted only when

the mailpieces contain button cell batteries meeting the

classification criteria in 349.11d, the batteries are properly

installed in the equipment they are intended to operate, and the

batteries are afforded adequate protection by that equipment.

(7) Except for mailpieces containing button cell batteries installed in

equipment (including circuit boards), or no more than 4 lithium-

ion cells or 2 lithium-ion batteries installed in the equipment they

operate, mailpieces containing lithium-ion batteries must bear a

DOT-approved lithium battery mark, as specified in 49 CFR

173.185(c)(3)(i) and Exhibit 325.2a, applied to the address side of

349.222 Hazardous, Restricted, and Perishable Mail

90 Publication 52

the mailpiece. Marks must not be applied in such a manner that

parts of the mark appear on different sides of the mailpiece.

Where the lithium cells or batteries are shipped separately from

equipment, the mark must indicate UN3480. Where the lithium

cells or batteries are contained in, or packed with, equipment,

UN3481 must be indicated. The mark must also include a

telephone number for those who need to obtain additional

information.

(8) All used, damaged, or defective lithium-ion cells or batteries or

electronic devices contained in or packed with lithium-ion cells or

batteries (excluding electronic devices that are new in original

packaging, and manufacturer-certified new or refurbished

devices) must be marked with the text “Restricted Electronic

Device” and “Surface Transportation Only” on the address side

of the mailpiece.

b. Installed in Equipment. The following additional restrictions apply to the

mailing of lithium-ion cells or batteries properly installed in equipment

they operate:

(1) The batteries installed in the equipment must be protected from

damage and short circuit.

(2) The equipment must be equipped with an effective means of

preventing it from being inadvertently turned on or activated.

(3) The equipment must be cushioned to prevent movement or

damage and, unless excepted under 349.222a(6), must be

contained in rigid outer packaging, sealed and strong enough to

prevent crushing of the package or exposure of the contents

during normal handling in the mail.

(4) For lithium-ion cells and batteries with a watt-hour rating of not

more than 2.7 Wh, no mailpiece may exceed 2.5 kilograms

(5.5

pounds). There is no maximum number of cells or batteries

per mailpiece.

(5) For lithium-ion cells with a watt-hour rating of not more than

Wh, and batteries with a watt-hour rating of not more than

100

Wh, each mailpiece must contain no more than 8 cells or

batteries. Each cell must have a watt-hour rating of no more

than 20 Wh, and each battery must have a watt-hour of no more

than 100 Wh.

(6) When required or optionally applied, mailpieces must display a

DOT-approved lithium battery mark on the address side.

(7) DOT-approved lithium battery markings must be applied to all

mailpieces when there are more than two mailpieces in a single

consignment as defined in 349.12b.

c. Mailed With Equipment. The following additional restrictions apply to

the mailing of lithium-ion cells or batteries shipped with (but not

installed in) the device or equipment being mailed:

(1) For lithium-ion cells and batteries with a watt-hour rating of not

more than 2.7 Wh, no mailpiece may exceed 2.5 kilograms

Hazardous Materials 349.222

September 7, 2023 91

(5.5 pounds). There is no maximum number of cells or batteries

per mailpiece.

(2) For lithium-ion cells with a watt-hour rating of not more than

Wh, and batteries with a watt-hour rating of not more than

100

Wh, each mailpiece must contain no more than 8 cells or

batteries. Each cell must have a watt-hour rating of no more

than 20 Wh, and each battery must have a watt-hour of no more

than 100 Wh.

(3) The shipment must be cushioned to prevent movement or

damage, and must be contained in rigid outer packaging, sealed

and strong enough to prevent crushing of the package or

exposure of the contents during normal handling in the mail.

(4) Mailpieces must display a DOT-approved lithium battery mark on

the address side.

d. Mailed Without Equipment. The following additional restrictions apply

to the mailing of lithium-ion cells or batteries without equipment

(individual batteries):

(1) The lithium-ion cells and batteries must be mailed in “the

originally sealed packaging.”

(2) The sealed packages of batteries must be separated and

cushioned to prevent short circuit, movement, or damage.

(3) The shipment must be cushioned to prevent movement or

damage, and must be contained in rigid outer packaging, sealed

and strong enough to prevent crushing of the package or

exposure of the contents during normal handling in the mail.

(4) Unless both mailed from, and intended for delivery to, the state

of Alaska under 349.222d(7), mailpieces must be sent by surface

transportation only.

(5) The mailpiece must not exceed 5 pounds.

(6) Mailpieces must display a DOT-approved lithium battery mark on

the address side, in addition to the text “Surface Mail Only,

Secondary Lithium Batteries — Forbidden for Transportation

Aboard Passenger Aircraft” or “Surface Mail Only, Lithium-ion

Batteries — Forbidden for Transportation Aboard Passenger

Aircraft.”

(7) Cells having a watt-hour rating of not more than 20 Wh, and

batteries having a watt-hour rating of not more than 100 Wh may

be mailed via air transportation only when both mailed from, and

intended for delivery within, the state of Alaska. Each mailpiece

must contain no more than 8 cells or 2 batteries.

(8) Mailpieces must display a DOT-approved lithium battery mark on

the address side.

349.23 Hazardous, Restricted, and Perishable Mail

92 Publication 52

Exhibit 349.222

Domestic Lithium Battery Mailability

Surface

Transportation

Air

Transportation

Mailpiece

Limitations

Lithium Metal or Lithium Alloy Batteries

3, 4

Small, non-rechargeable, consumer-type batteries

Contained in (properly installed in

equipment)

Mailable Mailable 8 cells or 2 batteries

11 lbs.

Packed with equipment, but not installed in

e equipment

Mailable Mailable 8 cells or 2 batteries

11 lbs.

Without the equipment they operate

(individual batteries in originally sealed

packaging)

Mailable Prohibited 5 lbs.

Lithium-ion or Lithium Polymer Batteries

5, 6

Small, rechargeable, consumer-type batteries

Contained in (properly installed in

equipment)

Mailable Mailable 8 cells or 2 batteries

Packed with equipment, but not installed in

e equipment

Mailable Mailable 8 cells or 2 batteries

Without the equipment they operate

(individual batteries in originally sealed

packaging)

Mailable Prohibited

5 lbs.

Very Small Lithium Metal or Lithium-ion Batteries

8, 9

Exception for very small consumer-type batteries in USPS air transportation

Contained in (properly installed in

equipment)

Mailable Mailable No limit on cells/

batteries

5.5 pounds

Packed with equipment, but not installed in

the equipment

Mailable Mailable No limit on cells/

batteries

5.5 pounds

Damaged, Defective, or Recalled

Batteries

Prohibited, unless approved by the director, Product Classification.

1. Used, damaged, or defective electronic devices are prohibited from air transportation. This excludes devices that are new in

original packaging, and manufacturer-certified new or refurbished devices.

2. When a mailpiece limitation of 8 cells or 2 batteries is applicable, a mailpiece may co

ntain either 8 cells or 2 batteries, not both.

3. Each cell must not contain

more than 1 g (gram) of lithium content.

4. Each battery must not con

tain more than 2 g aggregate lithium content.

5. Each cell must not exceed more than 20

Wh (watt-hour rating).

6. Each battery must not exceed 100 Wh.

7. Mailable intra-Alaska via air transportation is limited to 8

cells or 2 batteries.

8. Each lithium metal or lithium alloy cell or batter

y must not exceed 0.3 g of lithium content.

9. Each lithium-ion or lithium polymer cell or

battery must not exceed 2.7 Wh.

349.23 Dry Ice

349.231 General

Dry ice is primarily used to keep other items cool. The items being cooled

can be either mailable hazardous materials or nonhazardous items, such as

medical specimens or foods.

Hazardous Materials 349.241

September 7, 2023 93

349.232 Characteristics and Precautions

Dry ice (carbon dioxide solid) is produced by expanding liquid carbon dioxide

to vapor and compacting the material into blocks. When dry ice converts

(dissipates) to a gaseous form, it takes in heat from its surroundings. The

resulting gas is heavier than air and can cause suffocation in confined areas

as air is displaced. When dry ice is enclosed in a thick metal or other

restrictive type of container, internal pressure builds up and could cause the

container to rupture or explode. Mailpieces containing dry ice must be

handled with care because its very low temperature (about –110° F

or –79° C) can cause severe burns to skin upon direct contact.

349.233 Dry Ice Mailability

Dry ice is permitted to be mailed when it is used as a refrigerant to cool the

content of a mailable hazardous or nonhazardous material. Packages

containing dry ice must be packed in containers that permit the release of

carbon dioxide gas and conform to 49 CFR 173.217 and 175.10(a)(10).

Mailpieces containing dry ice are subject to the following conditions, as

applicable:

a. International Mail. Dry ice is prohibited.

b. Domestic Mail via Air Transportation. Dry ice is permitted in quantities

of up to 5 pounds per mailpiece. Mailpieces containing dry ice are

subject to the conditions for Packaging Instruction 9A in Appendix

as applicable.

c. Domestic Mail via Surface Transportation. A mailpiece sent via surface

transportation may contain more than 5

pounds of dry ice. Mailpiece

preparation is subject to the conditions for Packaging Instruction 9A in

Appendix

Note: A mailpiece that is prepared for surface transportation must

not, under any circumstances, be routed via air transportation.

349.24 Magnetized Materials

A magnetized material is not classified within any of the nine hazard classes.

Such material is regulated as a hazardous material only if offered for carriage

on air transportation and when it has a magnetic field strength capable of

causing the deviation of aircraft instruments.

349.241 Definition

A magnetized material is any article that has a magnetic field strength

capable of causing the deviation of aircraft instruments. A magnetized

material is regulated as a hazardous material when it is presented for air

transportation and has a measurable magnetic field strength greater than

0.00525 gauss at 15

feet. Magnetized materials include magnets and

magnetized devices such as magnetrons and light meters of sufficient

strength to possibly cause erroneous aircraft compass readings. If the

maximum field strength observed at a distance of 7 feet is less than

0.002 gauss or there is no significant compass deflection (less than

0.5 degree), the article is not restricted as a magnetized material.

349.242 Hazardous, Restricted, and Perishable Mail

94 Publication 52

349.242 Mailability

Magnetized materials that have a magnetic field strength of 0.002 gauss or

more at a distance of 7 feet from any point on the surface of the outer

packaging are mailable via air transportation if properly packaged.

Magnetized materials that have a field strength greater than 0.00525 gauss

at 15 feet are nonmailable under any conditions. The following requirements

also apply:

a. International Mail. O

nly non-regulated magnetized materials that have a

magnetic field strength less than 0.002 gauss at a distance of 7 feet

may be sent internationally. Magnetized materials which are regulated

are prohibited. See

622.4 or IMM 136.1.

b. D

omestic Mail via Air Transportation. Magnetized materials that have a

magnetic field strength greater than 0.00525 gauss at 15 feet are

prohibited. A magnetic field strength less than 0.002 gauss at a

distance of 7 feet is not regulated. Mailpiece preparation is subject to

the conditions in Packaging Instruction 9B in Appendix

C. The address

side of the outer packaging must bear the magnetized material warning

label shown in

Exhibit 349.242b and a shipping paper is required, if

regulated.

c. D

omestic Mail via Surface Transportation. Magnetized material is not

regulated as a hazardous material when transported via surface

transportation.

Exhibit 349.242b

Warning Label for Magnetized Materials

349.3 Packaging

For mailable Class 9 materials, the following packaging requirements as

detailed in the Packaging Instructions in Appendix

C apply:

a. Packaging Instruction 9A must be followed for mailable quantities of dry ice.

b. Packaging Instruction 9B must be followed for mailable types of

gnetized materials.

c. Packaging Instruction 9C must be

followed for Class 9 miscellaneous

hazardous materials that can qualify as air-eligible consumer

commodity material (ID8000) when intended for air transportation or a

Limited Quantity ground material when intended for surface

transportation.

Hazardous Materials 349.4

September 7, 2023 95

d. Packaging Instruction 9D must be followed for lithium and lithium-ion

cells and batteries.

349.4 Marking and Documentation

Parcels containing mailable Class 9 material must be marked as follows:

a. For air transportation, a mailpiece Class 9 material must bear the DOT

square-on-point marking. The top and bottom portions of the square-

on-point and the border forming the square-on-point must be black,

and the center must be white or of a suitable contrasting background.

The symbol “Y” must be black, located in the center of the square-on-

point, and clearly visible. Mailpieces intended for transport by air and

containing eligible limited quantity material of DOT Classes 2, 3, and

6.1, or eligible hazard Class 9 limited quantity material categorized in

UN3077, UN3082, UN3175, UN3334, or UN3335, must be marked with

the proper shipping name “Consumer Commodity” and identification

number “ID8000.” Each mailpiece must also display an approved DOT

Class 9 hazardous material warning label (see

Exhibit 325.3b). A

shipper’s declaration for dangerous goods that is prepared in triplicate

must be affixed to the outside of the mailpiece.

b. For surface transportation, parcels containing mailable Class 9

materials must be plainly and durably marked on the address side with

an approved DOT Limited Quantity ground marking unless specified in

221.1 and 325.1 (see 325.4). Surface shipments bearing the Limited

Quantity ground marking are not required to include the proper

shipping name and identification number.

c. When the DOT square-on-point markings are used, markings must be

durable, legible, and readily visible, and must be applied on at least

one side or one end of the outer packaging. The border forming the

square-on-point must be at least 2 mm in width, and the minimum

dimension of each side must be 100 mm, unless the package size

requires a reduced size marking of no less than 50 mm on each side.

d. The specific marking and documentation requirements for dry ice,

magnetized materials, and lithium batteries are specified in Packaging

Instruction 9A, Packaging Instruction 9B, and Packaging Instruction 9D

in Appendix C, as applicable.

349.4 Hazardous, Restricted, and Perishable Mail

96 Publication 52

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September 7, 2023 97

4 Restricted Matter

41 General

411 Definition

Restricted matter includes articles on which mailing restrictions have been

imposed for reasons other than risk of harm to persons or property involved

in moving the mail. Motor vehicle master keys and intoxicating liquors are

examples of restricted items.

412 Mailer Responsibility

The mailer is responsible for ensuring that all Postal Service requirements, as

well as all federal and state laws and local ordinances that apply to the

shipment of an article of restricted matter, have been met.

413 Rulings

Where doubt exists about mailability of any article that is considered to be

restricted matter, a request for a ruling may be made to the local postmaster

(see

215.3).

When the qualification of an addressee to receive restricted matter within the

conditions in this chapter is in question, a Postmaster may require the mailer

or addressee to furnish a written explanation of the addressee’s eligibility

and/or the item’s mailability. If the explanation is not satisfactory or when

uncertainty remains, the postmaster may forward the explanation along with

a statement of the facts to the PCSC for a ruling.

414 Nonmailable Matter Found in the Mails

All nonmailable articles of restricted matter discovered in the mailstream

must immediately be reported in accordance with the provisions in the Postal

Operations Manual (POM) 139.117 or 139.118, as appropriate.

42 Intoxicating Liquors

421 Definition

Intoxicating liquors are drinkable beverages that have 0.5 percent or more

alcoholic content by weight and are taxable under Chapter 51 of the Internal

Revenue Service (IRS) Code.

422 Hazardous, Restricted, and Perishable Mail

98 Publication 52

422 Mailability

422.1 Nonmailable Matter

422.11 Intoxicating Liquors

Intoxicating liquors having 0.5 percent or more alcoholic content are

nonmailable. Taxable liquors (as defined by Chapter 51, Internal Revenue

Service Code) with 3.2 percent or less alcohol, including those obtained

under a prescription or as a collector’s item, also are nonmailable. The

prohibition of the mailing of intoxicating liquors is contained in federal law

(18

U.S.C. 1716).

422.12 Promotional Materials

Advertising, promotional, or sales matter that solicits or induces the mailing

of intoxicating liquors also is nonmailable. See DMM 601.7.4.1.

422.2 Mailable Liquors

422.21 Products Not Categorized As Intoxicating Liquors

A product containing an intoxicating liquor is mailable if it conforms to the

applicable requirements of the IRS and the Food and Drug Administration

(FDA), and if it is not a taxable alcoholic beverage, poisonous, or flammable.

The following are examples of products that may be mailable:

a. Cold remedies.

b. Cooking wine.

c. Mouthwash.

422.22 Exempt Mailings Between Federal and State Agencies

Intoxicating liquor is exempt from the prohibition against mailing when it is

sent between employees of federal or state agencies who have an official

use for the liquor, such as for testing purposes. This exemption is based on

the intent of the law to prevent liquor from being transported to prohibited

jurisdictions for consumption and to ensure that all proper tax revenues are

paid.

423 Packaging and Marking

423.1 General

All exempt intoxicating liquors must be sent via Registered Mail service and

must meet the packaging requirements for liquids in DMM 601.3.4.

423.2 Denatured Flammable or Combustible Liquor

There are no postal requirements to denature the contents (i.e., to change

the nature or natural qualities) of intoxicating liquor. However, if contents are

denatured through the use of such elements as sodium bisulfate (a corrosive)

or mercuric chloride (a poison), the substances must meet the mailability

requirements in Chapter

3 for a Class 8 corrosive material or a Division 6.1

toxic substance, as appropriate. If the contents are flammable or

combustible, the material must meet the requirements for a Class 3

flammable or combustible liquid in Chapter

Restricted Matter 431.3

September 7, 2023 99

43 Firearms

431 Definitions

431.1 Firearm

The following definitions apply:

a. Firearm means any device, including a starter gun, which will, or is

designed to, or may readily be converted to, expel a projectile by the

action of an explosive; the frame or receiver of any such weapon; any

firearm muffler or firearm silencer; or any destructive device; but the

term shall not include antique firearms (except antique firearms

meeting the description of a handgun or of a firearm capable of being

concealed on a person).

b. Firearm frame or receiver is the part of a firearm which provides

housing for the hammer, bolt or breechblock, and firing mechanism,

and which is usually threaded at its forward portion to receive the

barrel. Frames and receivers usually (but not always) include the

firearm serial number and are usually considered to be the regulated

component of a firearm.

431.2 Handguns

Pistols, revolvers, and other firearms capable of being concealed on the

person (for example, short-barreled shotguns and short-barreled rifles) are

defined as handguns. The following definitions apply:

a. Handgun (including pistols and revolvers) means any firearm which has

a short stock, and is designed to be held and fired by the use of a

single hand and subject to

431.1, or a combination of parts from which

a handgun can be assembled.

b. Other firearms capable of being concealed on the person include, but

are not limited to, short-barreled shotguns and short-barreled rifles.

c. Short-barreled shotgun means a shotgun that has one or more barrels

less than 18 inches long. The term short-barreled rifle means a rifle that

has one or more barrels that are less than 16 inches long. These

definitions include any weapon made from a shotgun or rifle, whether

by alteration, modification, or otherwise, if such a weapon as modified

has an overall length of less than 26 inches. A short-barreled shotgun

or rifle of greater dimension may be regarded as nonmailable when it

has characteristics to allow concealment on the person.

431.3 Antique Firearm

Antique firearm means any muzzle loading rifle/shotgun/pistol, which is

designed to use black powder or a black powder substitute, and which

cannot use fixed ammunition (except those that incorporate a firearm frame

or receiver, any firearm which is converted into a muzzle loading weapon, or

any muzzle loading weapon which can be readily converted to fire fixed

ammunition by replacing the barrel, bolt, breechblock, or any combination

431.4 Hazardous, Restricted, and Perishable Mail

100 Publication 52

thereof); or any firearm (including those with a matchlock, flintlock,

percussion cap, or similar type of ignition system) manufactured on or before

1898, or any replica thereof, if such replica:

a. Is not designed or redesigned for using rimfire or conventional

centerfire fixed ammunition.

b. Uses rimfire or conventional centerfire fixed ammunition that is no

longer manufactured in the United States and is not readily available in

the ordinary channels of commercial trade.

431.4 Rifles and Shotguns

A rifle is a shoulder weapon having a barrel that is 16 inches or more in

length. A shotgun is a shoulder weapon having a barrel that is 18 inches or

more in length. Rifles and shotguns have an overall length of 26 inches or

greater and cannot be concealed on a person.

431.5 Federal Firearms Licensee (FFL)

Federal Firearms licenses are issued by the Bureau of Alcohol, Tobacco, and

Firearms (ATF), U.S. Department of the Treasury, under the Gun Control Act

of 1968, and are defined as follows:

a. Federal Firearms Licensee (FFL) manufacturer, dealer, or importer of

firearms means a manufacturer, dealer, or importer duly licensed by

the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) under

Chapter 44, Title 18, United States Code (U.S.C.).

b. Curio and relic collector means an individual licensed by ATF to

transfer or receive only those firearms defined as curios or relics by

ATF under Title 27, Code of Federal Regulations (CFR), section 478.11.

431.6 Air Guns

Air gun means a gun that fires a projectile by means of compressed air or

other gas (including paintball and pellet guns).

432 Mailability

432.1 General

Mailers must comply with the Gun Control Act of 1968, all of the provisions

of postal law in 18 U.S.C. 1715, and all other all federal and state regulations

and local ordinances affecting the movement of firearms. The following also

applies:

a. The Postal Service may require the mailer to open parcels containing

firearms or air guns or give written certification that the weapon is

unloaded and not concealable.

b. Short-barreled rifles or shotguns that can be concealed on the person

are nonmailable.

c. No markings of any kind that indicate the nature of the contents may

be placed on the outside wrapper or container of any mailpiece

containing firearms.

Restricted Matter 432.21

September 7, 2023 101

d. Mailable matter must be properly and securely packaged within the

general packaging requirements in DMM 601.1-7.

e. Except for shipments between licensed dealers, manufacturers, or

importers, all regulated firearms must be mailed using a USPS product

or Extra Service that provides tracking and signature capture at

delivery.

432.2 Handguns

Handguns and other firearms capable of being concealed on the person are

nonmailable unless mailed between the parties listed in this section, after the

filing of an affidavit or statement described in

432.22 or 432.24, and are

subject to the following:

a. Firearms meeting the definition of a handgun under 431.2 and the

definition of curios or relics under 27 CFR 478.11 may be mailed

between curio and relic collectors only when those firearms also meet

the definition of an antique firearm under

431.3.

b. Firearms meeting the definition of a handgun under 431.2, which are

certified by the curator of a municipal, state, or federal museum that

exhibits firearms to be curios or relics of museum interest, may be

accepted for mailing between governmental museums without regard

to the restrictions provided for handguns in

432.21 through 432.24 and

Exhibit 432.25.

c. Air guns (see 431.6) that do not fall within the definition of firearms

under 431.1 and are capable of being concealed on a person are

mailable, but must include Adult Signature service under DMM 503.8.

Mailers must comply with all applicable state and local regulations.

d. Parts of handguns are mailable, except for handgun frames, receivers or

other parts or components regulated under Chapter 44, Title 18, U.S.C.

e. Mailers are also subject to applicable restrictions by governments of a

state, territory, or district.

432.21 Authorized Persons

Subject to 432.22, handguns may be mailed by a licensed manufacturer of

firearms, a licensed dealer of firearms, a licensed importer of firearms, or an

authorized agent of the federal government or the government of a state,

territory, or district, only when addressed to a person in one of the following

categories for use in the person’s official duties, and upon filing the required

affidavit or certificate:

a. Officers of the Army, Coast Guard, Air Force, Navy, Marine Corps, or

Organized Reserve Corps.

b. Officers of the National Guard or militia of a state, territory, or district.

c. Officers of the United States or of a state, territory, or district, whose

official duty is to serve warrants of arrest or commitment.

d. USPS employees authorized by the Chief Postal Inspector.

e. Officers and employees of enforcement agencies of the United States.

f. Watchmen engaged in guarding the property of the United States, a

state, territory, or district.

432.22 Hazardous, Restricted, and Perishable Mail

102 Publication 52

g. Purchasing agent or other designated member of agencies employing

officers and employees included in

432.21c through e.

432.22 Affidavit of Addressee

Any person proposing to mail a handgun under 432.21 must file with the

Postmaster, at the time of mailing, an affidavit signed by the addressee

setting forth that the addressee is qualified to receive the firearm under a

particular category of

432.21a through 432.21g, and that the firearm is

intended for the addressee’s official use. The affidavit must also bear a

certificate stating that the firearm is for the official duty use of the addressee,

signed by one of the following, as appropriate:

a. For officers of Armed Forces, by the commanding officer.

b. For officers and employees of enforcement agencies, by the head of

the agency employing the addressee to perform the official duty with

which the firearm is to be used.

c. For watchmen, by the chief clerk of the department, bureau, or

independent branch of the government of the United States, the state,

the territory, or the district by which the watchman is employed.

d. For the purchasing agent or other designated member of enforcement

agencies, by the head of such agency, that the firearm is to be used by

an officer or employee included in

432.21c through 432.21e.

432.23 Manufacturers, Dealers, and Importers

Handguns may also be mailed between licensed manufacturers of firearms,

licensed dealers of firearms, and licensed importers of firearms in customary

trade shipments, or for repairing or replacing parts.

432.24 Certificate of Manufacturers, Dealers, and Importers

A federal firearms licensee manufacturer, dealer, or importer need not file the

affidavit under

432.22, but must file with the Postmaster a statement on

PS Form 1508, Statement by Shipper of Firearms, signed by the mailer that

he or she is a licensed manufacturer, dealer, or importer of firearms. The

mailer must also state that the parcels containing handguns, or parts and

components of handguns under

432.2d, are being mailed in customary trade

shipments or contain such articles for repairing or replacing parts, and that to

the best of their knowledge the addressees are licensed manufacturers,

dealers, or importers of firearms. Registered Mail service is recommended.

Postmasters may forward an unsatisfactory mailer statement to the PCSC for

a ruling.

432.25 Federal and Other Law Enforcement Agencies

Handguns may be mailed without regard to 432.21 through 432.24 if the item is:

a. Addressed to a scientific laboratory or crime detection bureau of any

federal, state, or local law enforcement agency whose members are

authorized to serve warrants of arrest or commitment.

Restricted Matter 432.3

September 7, 2023 103

b. Sent by an authorized agent of the federal government as an official

ipment to any qualified addressee in

432.21, or to a licensed

manufacturer, dealer, or importer of firearms, or to a federal agency.

Exhibit 432.25

Mailability Requirements for Handguns

Addressee Affidavit or Certificate Requirements

Officer of Air Force, Army, Coast

Guard,

Marine Corps, Navy, or Organized Reserve

Corps.

Affidavit signed by the addressee and certificate signed by the

commanding officer.

Officer of National Guard or militia of a state,

territory, or district.

Affidavit signed by the addressee and certificate signed by the

commanding officer.

Officer of the federal government or a state,

district, or territory whose official duty is to

serve warrants of arrest or commitment.*

Affidavit signed by the addressee and certificate signed by the

head of the agency employing the addressee.

Postal Service employees specifically

authorized by the Chief Postal Inspector.*

Affidavit signed by the addressee and certificate signed by the

head of the agency employing the addressee.

Officer or employee of a U.S. enforcement

agency.*

Affidavit signed by the addressee and certificate signed by the

head of the agency employing the addressee.

Purchasing agent or other designated member

of a

n enforcement agency employing officers

and personnel included in (*) above.

Affidavit signed by the addressee and certificate signed by the

head of agency stating the firearm is to be used by an officer or

employee included in addressee column marked with an (*).

Watchman engaged in guarding federal, state,

district, or territory property.

Affidavit signed by the addressee and certificate signed by chief

clerk of department, bureau, or independent branch of the

government agency employing the addressee.

Licensed manufacturers, importers, and

dealers of firearms.

Signed statement on PS Form 1508, Statement by Shipper of

Firearms. The mailer must be a licensed manufacturer, importer,

or dealer mailing to another licensed manufacturer, importer, or

firearms dealer.

432.3

Rifles and Shotguns

Except under 431.2, unloaded rifles and shotguns are mailable. Mailers must

comply with the rules and regulations un

der 27 CFR, Part 478, as well as

state and local laws. The mailer may be required by the USPS to establish,

by opening the parcel or by written certification, that the rifle or shotgun is

unloaded and not ineligible for mailing. The following conditions also apply:

a. Subject to state, territory, or district regulations, rifles and shotguns

may be mailed without

restriction when intended for delivery within the

same state of mailing. These items must:

(1) Bear a “Return Service Requested” endorsement.

(2) Be mailed using a class of mail, pr

oduct, or Extra Service that

provides tracking and signature capture at delivery.

b. A rifle or shotgun owned by a non-FFL may be mailed outside the

owne

r's state of residence by the owner to himself or herself, in care of

another person in the other state where he or she intends to hunt or

engage in any other lawful activity. These mailpieces must:

(1) Be addressed to the owner.

(2) Include the “in the care of” endorsement immediately preceding

e name of the applicable temporary custodian.

432.4 Hazardous, Restricted, and Perishable Mail

104 Publication 52

(3) Be opened by the rifle or shotgun owner only.

(4) Be mailed using a class of mail, product, or Extra Service that

provides tracking and signature capture at delivery.

c. Mailing of rifles and shotguns between licensed FFL dealers,

manufacturers, or importers are not restricted. The Postal Service

recommends that these items be mailed using a class of mail, product,

or Extra Service that provides tracking and signature capture at

delivery.

d. Rifles and shotguns may be mailed by a non-FFL owner domestically to

a FFL dealer, manufacturer, or importer in any state. These items must

be mailed using a class of mail, product, or Extra Service that provides

tracking and signature capture at delivery.

e. Except as described in 432.3a, licensed curio and relic collectors may

mail firearms meeting the definition of curios or relics under 27 CFR

478.11 domestically to licensed FFL curio and relic collectors in any

state. These items must be mailed using a class of mail, product, or

Extra Service that provides tracking and signature capture at delivery.

f. Firearms meeting the definition of a rifle or shotgun under 431.4 which

are certified by the curator of a municipal, state, or federal museum,

which exhibits firearms to be curios or relics of museum interest, may

be accepted for mailing without restriction when mailed between

governmental museums.

g. Air guns (see 431.6) that do not fall within the definition of firearms

under 431.1a are mailable. A shipment containing an air gun with a

muzzle velocity of 400 or more feet per second (fps) must include an

adult signature service under DMM 503.8. Mailers must additionally

comply with all applicable state and local regulations.

432.4 Indemnity Claims

When indemnity claims pertaining to regulated firearms are filed for loss or damage to

contents, claims will only be paid for complete loss under either of the following con-

ditions:

a. The regulated firearm has been lost, or

b. When the mailer has provided reasonable estimates of the firearm’s

value and of repair cost from a reputable dealer, and the repair cost

exceeds the declared and/or actual value of the firearm at the time of

mailing.

433 Legal Opinions on Mailing Firearms

Postmasters are not authorized to give opinions on the legality of any

shipment of firearms. Mailers requesting additional information should be

referred to the ATF. Further advice and ATF contact information is available

http://atf.gov/firearms/faq/licensing.html.

Restricted Matter 442

September 7, 2023 105

434 Replica or Inert Explosive Devices

Replica or inert explosive devices that are not dangerous, but that bear a

realistic appearance to explosive devices such as simulated grenades, are

permitted in the mail when all of the following conditions are met:

a. The package is presented by the mailer at a retail counter.

b. Registered Mail service is used.

c. The address side of the package is labeled with “REPLICA EXPLOSIVE”

using at least 20-point type or letters at least 1/4-inch high.

435 Nonmailable Firearms Found in the Mails

Nonmailable firearms discovered in the mailstream must be immediately

reported to the Inspection Service in accordance with POM 139.117.

44 Knives and Sharp Instruments

441 Definitions

441.1 General

Sharp instruments include all sharp-pointed or sharp-edged implements

such as knives, tools, ice picks, razor blades, stilettos, or similar devices.

When uncertain about the mailability of a sharp instrument or a switchblade

knife, a ruling may be requested from the local postmaster (see

215.3).

441.2 Switchblade Knife

A switchblade knife has a blade that opens automatically by hand pressure

applied to a button or other device in the handle, or by operation of inertia,

gravity, or both.

442 Mailability

A switchblade knife, as defined in 441.2, is mailable only to the following

categories of addressees:

a. Certain designated supply or procurement officers and employees

ordering, procuring, or purchasing them for use in connection with their

respective governments or organizations, such as:

(1) Civilian or armed forces supply or procurement officers, and

employees of the federal government.

(2) Supply or procurement officers of the National Guard, the Air

National Guard, or the militia of a state, territory, or the District of

Columbia.

(3) Supply or procurement officers or employees of the municipal

government of the District of Columbia, or of the government of

any state or territory, or of any county, city, or other political

subdivision of a state or territory.

Note: Addressee Identification. Before delivering a shipment (or

parcel) that contains an article or articles described in

441.2, a

443 Hazardous, Restricted, and Perishable Mail

106 Publication 52

USPS employee may require that the recipient identify himself or

herself as being in one of the categories in

442a.

b. Manufacturers or bona fide dealers of such knives in connection with a

shipment made to an address in one of the above categories.

443 Packaging and Marking

443.1 General

All sharp-pointed or sharp-edged instruments such as knives, tools, ice

picks, razor blades, etc., that are otherwise mailable, must be securely

packaged in a strong container. An inner and outer packaging container is

recommended. Sufficient cushioning material must be used to protect the

sharp points and edges from cutting through the outer packaging during

normal Postal Service handling.

443.2 Marking

No marking of any kind that indicates the nature of the contents may be

placed on the outside of any mailpiece containing a switchblade knife.

444 Nonmailable Knives in the Mails

Nonmailable knives or sharp instruments discovered in the mailstream must

be reported to the Inspection Service in accordance with POM 139.117.

45 Other Restricted Materials

451 Liquids, Powders, and Odor-Producing Materials

451.1 Definitions

A liquid is any substance that flows readily and assumes the form of the

container, but retains an independent volume. For the purposes of

mailability, a liquid may be a cream or paste or any other nonhazardous

substance (except a gas) that may liquify under existing conditions.

An odor is any matter that is a source of an obnoxious odor.

451.2 Mailability

a. Liquids and powders that are nonhazardous (i.e., not regulated as

hazardous materials) are mailable provided they are properly packaged

as specified in

451.3.

b. Any matter that is a source of an obnoxious odor is nonmailable.

451.21 Restrictions

Liquids and powders that are corrosive, explosive, flammable, toxic, or

otherwise hazardous are subject to the mailing conditions for hazardous

materials in Chapter

3, as applicable.

Restricted Matter 451.3

September 7, 2023 107

451.22 Cremated Remains

The following applies when mailing cremated remains (ashes):

a. Domestic:

(1) Permitted for cremated remains (human or animal) only when

sent via Priority Mail Express service. The item must be

packaged as required in

451.3b and Packaging Instruction 10C.

(2) The Priority Mail Express mailpiece (USPS-produced or customer

supplied) must be marked with Label 139, Cremated Remains,

affixed to all sides (including top and bottom), or a mailer may

use the special Priority Mail Express cremated remains branded

box (BOX-CRE) available on

usps.com.

(3) Mailers may have a shipping label printed and affixed at a Post

Office location or mailers may generate single-ply Priority Mail

Express labels through Click-N-Ship or other USPS-approved

methods. Mailer generated labels must bear an Intelligent Mail

package barcode (IMpb) with the proper cremated remains

service type code and include the proper Extra Services code in

the Shipping Services File (see Publication

199 on PostalPro at

postalpro.usps.com).

(4) Priority Mail Express mailpieces containing cremated remains are

limited to additional insurance and return receipt extra services.

b. International:

(1) When permitted by the destination country, cremated remains

(human or animal) may only be sent via Priority Mail Express

International service. Mailers must verify that the destination

country accepts Priority Mail Express International and cremated

remains before mailing. The contents must be indicated on the

applicable customs declaration form. The item must be

packaged as required in

451.3b and Packaging Instruction 10C.

(2) The Priority Mail Express International mailpiece (USPS-

produced or customer supplied) must be marked with a

Label

139, Cremated Remains, affixed to all sides (including top

and bottom), or a mailer may use the special Priority Mail Express

cremated remains branded box (BOX-CRE) available on

usps.com.

451.3 Packaging and Marking

The following conditions apply:

a. L

iquids. Nonhazardous liquids, creams, and pastes, particularly those

in 1-gallon paint cans with only friction-top closures (push-down tops),

are often a source of damage to other mail and postal equipment. The

proper packaging of liquids is critical to ensuring the integrity of the

mailpiece during handling. Mailers must mark the outer container of a

mailpiece containing liquid to indicate the nature of the contents, and

include orientation arrows in accordance with

226. All liquids are

452 Hazardous, Restricted, and Perishable Mail

108 Publication 52

subject to the general packaging requirements in DMM 601.3.4 and the

following:

(1) Containers having friction-top closures are not acceptable by

themselves. Such containers must be packed within a strong and

securely sealed outer packaging.

(2) The use of locking rings or similar devices is encouraged when

mailing containers with friction-top closures (push-down tops).

(3) Screw caps with a minimum of one and one-half turns, soldering

clips, or other effective means must be used to ensure a secure

closure.

(4) All nonmetal containers of liquid more than 4 ounces, including

plastic containers, and metal containers with friction top

closures, must be triple-packaged, and include absorbent

material capable of absorbing all of the liquid in the container(s)

in case of breakage, a leakproof secondary container, such as a

watertight can or plastic bag surrounding the primary

container(s), and an outer mailing container that is securely

sealed, strong enough to protect the contents, and durable

enough to withstand normal processing in Postal Service

networks.

(5) Steel pails and drums with carrying handles and positive closures

(e.g., locking rings or recessed spouts under screw-cap closures)

may be accepted without additional packaging.

(6) As an alternative to 451.3a(4) above, mailers may use containers

certified by the International Safe Transit Association (ISTA) to

have passed ISTA‘s Test Procedure 3A. Mailers must, upon

request, provide written test results verifying that sample

mailpieces passed each test outlined in the standard and that no

liquids were released.

b. Powders and Cremated Remains. Dry materials that could cause

damage, discomfort, destruction, or soiling upon escape (leakage)

must be packed in siftproof containers or other containers that are

sealed in durable siftproof outer containers.

452 Motor Vehicle Master Keys and Locksmithing

Devices

452.1 Definitions

452.11 Motor Vehicle Master Keys

A motor vehicle master key is any of the following:

a. Motor vehicle master keys, as defined in 452.11, and any

advertisement for the sale of such items, are nonmailable unless sent

to any of the following categories of addressees:

b. The key (or an exact duplicate) furnished with a replacement lock.

Restricted Matter 452.4

September 7, 2023 109

c. Any key or manipulation device designed to operate two or more motor

vehicle ignition, door, or trunk locks of different combinations,

including any pattern, impression, or mold from which a master key or

manipulation device can be made (18 U.S.C. 1716 and

39 U.S.C. 3002).

452.12 Locksmithing Devices

A locksmithing device is any of the following:

a. A device or tool (other than a key) designed to manipulate the tumblers

in a lock into the unlocked position through the keyway of such lock.

b. A device or tool (other than a key or a device or tool under 452.12a)

designed for bypassing a lock or similar security device, or for opening

it by a method normally not used by consumers to open such locks or

security devices.

c. A device or tool designed for making an impression of a key or similar

security device in order to duplicate such key or device.

452.2 Mailability

The following conditions apply:

a. Motor vehicle master keys, as defined in 452.11, and any

advertisement for the sale of such items, are nonmailable unless sent

to any of the following categories of addressees:

(1) Lock manufacturers.

(2) Professional locksmiths.

(3) Motor vehicle manufacturers or dealers.

(4) Federal, state, or local government agencies.

b. Locksmithing devices, as defined in 452.11, are nonmailable except

when sent to any of the following categories of addressees:

(1) Lock manufacturers or distributors.

(2) Bona fide locksmiths.

(3) Bona fide repossessors.

(4) Motor vehicle manufacturers or dealers.

(5) Bona fide automotive repair shops or businesses.

452.3 Packaging and Marking

No marking of any kind that indicates the nature of the contents may be

placed on the outer wrapper or packaging of any mailpiece containing motor

vehicle master keys or locksmithing devices. Mailable matter must be

properly and securely packaged within the general requirements in

DMM

601.1-7.

452.4 Nonmailable Matter Found in the Mails

All nonmailable motor vehicle master keys and locksmithing devices

discovered in the mailstream must be reported in accordance with

POM

139.117.

453 Hazardous, Restricted, and Perishable Mail

110 Publication 52

453 Controlled Substances and Drugs

453.1 Definitions

453.11 Controlled Substances

A controlled substance is any anabolic steroid, narcotic, hallucinogenic,

stimulant, or depressant drug identified in Schedules I through V of the

Controlled Substances Act in 21 U.S.C. 801 and the implementing

regulations in 21 CFR 1300.

Controlled substances include poisons, compositions containing poisons,

poisonous drugs and medicines, or materials that may kill or injure within the

intent and meaning of 18 U.S.C. 1716.

453.12 Drugs

The term “drug” refers to:

a. Prescription drugs which are licensed medicines that require a written

order by a medical doctor or pharmacist before they can be obtained.

Certain poisonous (toxic) drugs and medicines may be subject to the

requirements for Division 6.1 materials in Chapter

b. Over-the-counter drugs which are medicines that can be obtained

without a prescription. This includes patent medicines and related

items such as aspirin, antiseptics, cold remedies, diet pills, and

cosmetic medicines that do not contain a controlled substance and are

not poisonous drugs or medicines.

453.13 Drug Paraphernalia

The term “drug paraphernalia” refers to any equipment, product, or material

primarily intended or designed for use in manufacturing, compounding,

converting, concealing, producing, processing, preparing, injecting,

ingesting, inhaling, or otherwise introducing into the human body a

controlled substance.

Examples of drug paraphernalia are items primarily intended or designed for

use in ingesting, inhaling, or otherwise introducing marijuana, cocaine,

hashish, hashish oil, PCP, or amphetamines into the human body, such as

metal, wooden, acrylic, glass, stone, plastic, or ceramic pipes with or without

screens, permanent screens, hashish heads, or punctured metal bowls;

water pipes, chamber pipes, carburetor pipes, electric pipes, ice pipes or

chillers, and air-driven pipes; carburetion tubes and devices; smoking and

carburetion masks; roach clips (i.e., objects used to hold burning material

that is too small or short to be held in the hand); miniature spoons with level

capacities of 1/10 cubic centimeter or less; chillums; bongs; wired cigarette

papers; and cocaine freebase kits.

453.131 Determination

In determining whether an item constitutes drug paraphernalia, in addition to

all other logically relevant factors, these factors may be considered:

a. Oral or written instructions or other descriptive materials provided with

the item that explain or depict its use.

b. National and local advertising on its use.

c. The manner in which the item is displayed for sale.

Restricted Matter 453.31

September 7, 2023 111

d. Whether the owner, or anyone in control of the item, is a legitimate

supplier of like or related items to the community, such as a licensed

distributor or dealer of tobacco products.

e. Direct or circumstantial evidence of the ratio of sales of the items to the

total sales of the business enterprise.

f. The existence and scope of legitimate uses of the item in the

community.

g. Expert testimony on its use.

453.132 Exceptions

The standards in 453.13 and 453.131 apply neither to any person authorized

by local, state, or federal law to manufacture, possess, or distribute items

described in

453.13 and 453.131; nor to any item that, in the normal lawful

course of business, is sold through the mail and traditionally intended for use

with tobacco products, including any pipe, paper, or accessory.

453.2 Mailer Responsibility

The mailer is fully responsible for the following:

a. Ensuring compliance not only with Postal Service regulations, but also

with all other federal laws and regulations, such as the Poison Prevention

Packaging Act and the Consumer Product Safety Act, and with all local

laws and regulations governing distribution of unsolicited samples.

b. Being aware of other characteristics of an article or substance, such as

its flammable, toxicity, or corrosive characteristics that may affect

mailability.

453.3 Mailability

453.31 Controlled Substances

If the distribution of a controlled substance is unlawful under 21 U.S.C. 801–971

or any implementing regulation in 21 CFR Chapter II, then the mailing of the

substance is also unlawful under 18 U.S.C. 1716.

Controlled substances and drugs that contain controlled substances are

acceptable in the domestic mail only under the following conditions:

a. For mailable controlled substances, generally both the mailer and

addressee must meet either of the following conditions:

(1) Be registered with the Drug Enforcement Administration (DEA).

(2) Be exempted from DEA registration, such as military, civil

defense, and law enforcement personnel, in performing official

duties.

b. For mail-back programs conducted in accordance with 453.7.

c. For prescription medicines containing mailable narcotic drugs

(controlled substances), when mailed by drug manufacturers or their

registered agents, pharmacies, medical practitioners, or other

authorized dispensers as permitted by 21 CFR 1307.11 or in

compliance with any regulation of the Food and Drug Administration or

other applicable law.

453.32 Hazardous, Restricted, and Perishable Mail

112 Publication 52

453.32 Drugs (Other Than Controlled Substances)

All prescription, nonprescription, and patent medicines and related items,

including solicited and unsolicited samples of such items, that are not

considered to be controlled substances under

453.11, are permitted to be

mailed as follows:

a. For prescription medicines containing a nonnarcotic drug(s), only a

pharmacist or medical practitioner, etc., who dispenses the medicine

may mail such substances to the patients under their care.

b. For nonprescription medicines, the mailer must meet all applicable

federal, state, or local laws that may apply (such as the Poison

Prevention Packaging Act of 1970 in 15 U.S.C. 1471(2) and the

Consumer Product Safety Commission requirements in 16 CFR 1700).

453.33 Poisonous Drugs and Medicines

Poisonous drugs and medicines may be sent only from the manufacturer or

dealer to licensed physicians, surgeons, dentists, pharmacists, druggists,

cosmetologists, barbers, and veterinarians (18 U.S.C. 1716). Some

poisonous drugs are subject to the requirements for Division 6.1 materials in

Chapter

453.34 Small Amounts for Law Enforcement Purposes

Nothing in this section precludes the mailing of small amounts of unknown

matter suspected of containing controlled substances to a federal, state, or

local law enforcement agency for law enforcement purposes. Such mailings

must comply with the applicable packaging requirements in

453.4.

453.35 Drug Paraphernalia

It is unlawful to use the mail to transport drug paraphernalia under the

Controlled Substances Act. If use of the mail to transport an article is

unlawful under the Controlled Substances Act, the article also is nonmailable

(see

453.13).

453.36 Return of Prescription Drugs

Mailers may use USPS Returns to return prescription drugs for purposes of

drug recalls; voluntary manufacturer withdrawals; and dispensing errors,

such as incorrect drug, dosage, or strength, as permitted by 21 CFR 1307.11

or other applicable law. The mailpiece must be addressed to the

manufacturer or its registered agent. Manufacturers or their registered

agents must furnish mailing containers to their customers to mail back the

identified drugs utilizing USPS Returns Service (see DMM 505.3.0) via

Priority Mail Return Service option for these mailpieces. Manufacturers or

their agents continue to be responsible for maintaining records in

compliance with any regulation of the U.S. Drug Enforcement Administration

or the U.S. Food and Drug Administration.

453.37 Hemp-based Products

For purposes of this section, “hemp” shall have the meaning provided under

federal law, including Section 10113 of the Agricultural Improvement Act of

2018, Pub. L.115-334 (7 U.S.C. § 1639o), or any successor provision.

Restricted Matter 453.5

September 7, 2023 113

Hemp and hemp-based products, including cannabidiol (CBD) with the

tetrahydrocannabinol (THC) concentration of such hemp (or its derivatives)

not exceeding a 0.3 percent limit are permitted to be mailed in domestic mail

only when:

a. The mailer complies with all applicable federal, state, and local laws,

and plans approved by the USDA under 7 CFR Part 990 pertaining to

hemp production, processing, distribution, and sales; and

b. The mailer retains records establishing compliance with such laws and

plans, including laboratory test results, licenses, or compliance reports,

for no less than 3 years after the date of mailing.

Shipments of hemp and hemp-based products, including cannabidiol (CBD),

are prohibited in international mail including items for delivery to overseas

military and diplomatic Post Office addresses (APO,

FPO, and DPO).

453.4 Packaging and Marking

Securely package all mailable drugs so that the contents cannot become

damaged or dislodged during mailing. The following conditions apply:

a. Controlled substances. The inner packaging of any mailpiece

containing a mailable controlled substance must be marked and sealed

in accordance with the applicable provisions and regulations of the

Controlled Substances Act (see

453.11). The inner packaging is also

labeled to show the prescription number and the name and address of

the pharmacy, practitioner, or other person dispensing the prescription

and must be securely held within a plain outer wrapper or packaging.

No markings of any kind that indicate the nature of the contents may

appear on the outside of the mailpiece. The general packaging

requirements in DMM 601.1-7 also apply.

b. Drugs and Medicines. Drugs and Medicines. Except for promotional

samples as described in

453.4c, each mailpiece containing a mailable

drug or medicine (that does not contain a controlled substance) must be

held in a plain outer wrapper or packaging.

c. Promotional Samples. A promotional sample package containing a

mailable over the counter, non-controlled, non-prescription drug or

medicine may bear a brief description of the sample as well as the

marking “Sample Enclosed” on the outside packaging of the mailpiece.

453.5 Rulings

Rulings must be based on the chemical composition of a product; the

composition of commercial products is ever-changing-e.g., the packaging

declares a “new and improved formula.”

Requests for rulings must include the trade name of the product, as well as

information regarding any known hazardous ingredients. A generic

description of the item (e.g., “tranquilizers”) is not sufficient. Requests for

rulings are directed to the local postmaster (see

215.3).

453.6 Hazardous, Restricted, and Perishable Mail

114 Publication 52

453.6 Nonmailable Matter Found in the Mails

Nonmailable controlled substances, drugs, and drug paraphernalia

discovered in the mailstream must be immediately reported in accordance

with POM 139.117.

453.7 Mail-back Programs

Effective October 9, 2014, the U.S. Department of Justice, Drug Enforcement

Administration (DEA), published the Federal Register final rule titled “Disposal

of Controlled Substances” (79 CFR 53519-53570), where it provided new

regulations specific to the collection and disposal of controlled substances.

This regulation authorized the use of DEA authorized mail-back collectors

(mailers) or law enforcement entities to conduct mail-back programs. Though

these programs authorize ultimate users who have lawfully obtained unused

or unwanted pharmaceuticals to transfer controlled substance

pharmaceuticals to authorized mail-back collectors for the purpose of

disposal, USPS authorization to conduct mail-back programs is subject to

the following conditions:

a. General

DEA registrants wishing to become controlled substances “mail-back

collectors” must obtain authorization from the DEA prior to conducting

a mail-back program, and must have the ability to destroy the returned

substances onsite. DEA-registered mail-back collectors must also

obtain an authorization from the USPS director, Product Classification,

before implementing any mail-back program. Mail-back programs may

only be authorized within the customs territory of the United States (the

50 states, the District of Columbia, and Puerto Rico).

b. Packaging

Authorized DEA registrants participating in a mail-back program must

provide users with ready-made packaging. All packaging used in mail-

back programs must:

(1) Be nondescript and must not include any markings or other

information that might indicate that the package contains

controlled substances.

(2) Be water- and spill-proof, tamper-evident, tear-resistant, and

sealable.

(3) Be preaddressed for delivery to the authorized mail-back

collector’s registered address or the participating law

enforcement’s physical address.

(4) Have postage pre-paid using one of the following products:

(a) Priority Mail Return Service; or

(b) Business Reply Mail parcels.

(5) Be accompanied by instructions for the user that describes the

process for mailing back the package, and other required

information.

Restricted Matter 454.1

September 7, 2023 115

c. Labels

Prior to requesting authorization, applicants (mailers) must:

(1) Implement a process for generating labels including unique

Intelligent Mail package barcodes, prepared in accordance with

DMM 708.5.1, Publication 199, and the Parcel Labeling Guide.

Publication 199 and the Parcel Labeling Guide are available on

PostalPro at

http://postalpro.usps.com/.

(2) Applicants must obtain written approval for their labels and

barcode quality from the National Customer Support Center

(NCSC) prior to submitting their request for authorization to

conduct a mail-back program.

d. Authorization

Mailers wishing to conduct a mail-back program must submit a letter of

request to the director, Product Classification (see DMM 608.8.1 for

address). Requests must include:

(1) The registrant’s name, address, and DEA certificate of

registration;

(2) The authorized mail-back collector’s DEA-registered location;

(3) An irrevocable $50,000 surety bond or letter of credit as proof of

sufficient financial responsibility to cover disposal costs if the

vendor ceases doing business to cover destruction costs of

residual mail-back envelopes that are in Postal Service

possession. The surety bond or letter of credit must be issued in

the name of the vendor seeking the authorization and must name

the Postal Service as the beneficiary or obligee;

(4) A letter of approval from the NCSC for each label type used to

conduct their mail-back program; and

(5) Sample mailpieces and labels intended for use with their mail-

back program.

e. Discontinuation

An authorized mail-back collector that terminates, transfers, or

discontinues business must provide the director, Product

Classification, with the name, registered address, and registration

number of the mail-back collector that will receive the remaining mail-

back packages, in accordance with DEA regulations.

453.8 Undeliverable Medicines

The disposition of undeliverable mailpieces containing drugs and medicines

is governed by POM 691.52

454 Unsolicited Promotional Samples

454.1 Definition

The term “unsolicited promotional sample” refers to any article of

merchandise that is sent through the mail free of charge and that is

unrequested by the addressee. This definition includes items such as patent

medicines, cosmetics, laundry products, and razors.

454.2 Hazardous, Restricted, and Perishable Mail

116 Publication 52

454.2 Mailability

454.21 General

The fact that an item is unsolicited by the addressee generally does not

affect its mailability unless the article is composed of hazardous materials or

restricted matter. Hazardous materials are subject to the mailing conditions

in Chapter

3 of this publication, as applicable. Unsolicited items that are not

hazardous materials may be subject to additional packaging requirements

based on the content.

454.22 Nonmailable Promotional Samples

454.221 Abortive and Contraceptive Devices or Materials

Any article or instrument designed, adapted, or intended for producing

abortion is nonmailable (18 U.S.C. 1461).

Unsolicited samples of an article or instrument designed, adapted, or

intended for preventing conception is nonmailable, except when mailed to a

manufacturer, dealer, licensed physician or surgeon, nurse, pharmacist/

druggist, or a hospital or clinic (39 U.S.C. 3001 and 18 U.S.C. 1461).

454.222 Restricted or Improperly Prepared Items

Other types of unsolicited samples may be nonmailable for other reasons,

including the following:

a. The sample is an otherwise restricted item such as a toxic substance

or poison subject to the hazardous materials requirements in

Chapter

b. The sample is improperly prepared for mailing, such as an inadequately

packaged razor blade or a household substance (39 U.S.C. 3001(f)),

i.e., any matter unsolicited by the addressee, that contains a substance

as defined by section 2 of the Poison Prevention Packaging Act of

1970 (15 U.S.C. 1471(2)), that does not comply with the child-resistant

packaging established for that substance by the Consumer Product

Safety Commission (16 CFR 1700).

c. The sample is a pesticide (18 U.S.C. 1716), i.e., any matter that

contains a pesticide as defined by section 2 of the Federal Insecticide,

Fungicide, and Rodenticide Act (7 U.S.C. 136(u)), that does not comply

with child-resistant packaging standards established by the

Environmental Protection Agency applicable to that particular matter

(40 CFR 157) and meets the applicable standards in 10.0.

d. A fragrance advertising sample (39 U.S.C. 3001(g)), i.e., any matter

normally acceptable in the mail but containing a fragrance advertising

sample, that does not comply with the requirements to be sealed,

wrapped, treated, or otherwise prepared in a manner reasonably

designed to prevent individuals from being unknowingly or involuntarily

exposed to the sample. A sample meets this requirement if it uses

paper stocks with a maximum porosity of 20 Sheffield units or

172

Gurley-Hill units treated exclusively with microencapsulated oils,

and if the sample is produced so that it cannot be activated except by

opening a glued flap or binder or by removing an overlying ply of paper.

Restricted Matter 455.2

September 7, 2023 117

e. The sample is an odd-shaped item in a letter-size envelope that is

prohibited under DMM 601.3.3.

454.3 Certificate Compliance

A mailer, who presents matter that is generally permitted in the mail, but for

compliance with the specified packaging and preparation requirements, may

submit an accompanying written statement certifying that the matter is

packaged or prepared under the applicable federal laws and postal

standards. The certifying statement may be made on the mailer’s letterhead,

on a postage statement, or as a notice on the exterior of each item presented

for mailing.

454.4 Customer Objection to Unsolicited Matter

Customers who object to receiving unsolicited matter should be advised that

the Postal Service must accept any lawfully mailable matter that is properly

prepared for mailing and bears appropriate postage. These customers may

be directed to contact the mailer or manufacturer to have their names

removed from the mailing list. Customers also may be advised they may

refuse any piece of mail, either at the time it is offered for delivery or after it is

delivered (if unopened), as provided in DMM 508.1 and POM 611.

454.5 Rulings

Rulings sometimes can be provided based on the trade name of an item, but

that is not always possible. A generic description, such as “razor blade,”

“cleaner,” “aerosol product,” or “drug,” is insufficient for determining

mailability. To request a ruling on the mailability of restricted matter, furnish

the information in

215.3 to the local postmaster.

If the matter for which the ruling is being requested has the physical

characteristics of a toxic substance, flammable liquid, compressed gas, or

other hazardous material, a ruling should be requested under the conditions

215.2.

455 Building Construction Material

455.1 Definition

The term “building construction material” refers to any material which is used

for construction purposes. Naturally occurring substances, such as clay,

rocks, sand, and wood, fit into this category and some of these substances

could be man-made products using synthetics.

455.2 Mailability

Building construction material is not permitted in the mail if the acceptance

and processing is likely to harm or injure USPS employees, mail, or

equipment. Factors considered include, but are not limited to, whether the

material may pose potential storage problems at the postal facilities that may

process the material; whether the volume of material may impede the flow of

mail in USPS transportation or mail distribution systems; whether the volume

of material may lead to security problems; and whether processing the

material may create safety hazards for USPS employees.

455.3 Hazardous, Restricted, and Perishable Mail

118 Publication 52

455.3 Rulings

Rulings must be based on the composition of the product. Requests for

rulings must include the trade name of the product, as well as information

regarding any known hazardous ingredients. A generic description of the

item is not sufficient. Requests for rulings are directed to the local

Postmaster (see

215.3).

455.4 Nonmailable Matter Found in the Mails

Nonmailable building construction material discovered in the mailstream

must be immediately reported in accordance with POM 139.117.

456 Lottery

456.1 Definition

The term “lottery” is any scheme or promotion, whether lawful under the laws

of any state, which, on paying a consideration, offers a prize dependent in

whole or in part on lot or chance. Lottery matter refers to any check, draft,

bill, money, postal note, or money order that is sent through the mail for the

purchase of any ticket or part thereof; for the purchase of any share or

chance in any such lottery, gift enterprise, or scheme; or for the payment of

prepaid taxes or fees purportedly required to collect lottery winnings.

456.2 Mailability

Mailed lottery tickets and related matter are statutorily defined as

nonmailable pursuant to 39 U.S.C. 3001, Nonmailable matter. Specifically, 39

U.S.C. 3001(a) states that matter deposited in the mail which is punishable

under 18

U.S.C. 1302, Mailing lottery tickets or related matter, is nonmailable

and subject to criminal penalties. The term “related matter” includes funds

remitted through the mail as noted in section

456.1 and DMM 601.9.3.

456.3 Nonmailable Determination

Excluding fishing contests, the Indian Gaming Regulatory Act, and lotteries,

as defined in DMM 601.9.3.3, the following, among other factors, may be

considered when determining whether a mailing constitutes nonmailable

lottery matter:

a. Statements made by the sender or recipient that the mailing contains

lottery-related material.

b. The mailing matches a pre-established profile of lottery-related

mailings based on the sender’s return address.

c. Evidence that the recipient address is used to receive lottery-related mailings.

Restricted Matter 462

September 7, 2023 119

46 Animal-Fighting Ventures

461 Definitions

461.1 Animal

For the purposes of participating in an animal-fighting venture, the term

“animal” refers to any live bird, dog, or other mammal (except human).

461.2 Animal-Fighting Venture

The term “animal-fighting venture” means any event, in or affecting interstate

or foreign commerce, that involves a fight conducted or to be conducted

between at least two animals for purposes of sport, wagering, or

entertainment (excluding any activity whose primary purpose involves using

one or more animals in hunting other animals).

461.3 Animal-Fighting Accessory

The term “animal-fighting accessory” refers to a knife, gaff, or other sharp

instrument attached to or designated or intended to be attached to the leg of

a bird in an animal-fighting venture.

461.4 Animal-Fighting Matter

Animal-fighting matter refers to written, printed, or graphic matter (e.g.,

advertisements or other commercial speech) promoting or furthering an

animal-fighting venture.

462 Mailability

a. The mailing of a live animal for the purpose of participating in an

animal-fighting venture, as defined in

461.2, is prohibited regardless of

whether such venture is permitted under a United States state, district,

commonwealth, territory, or possession in which it is conducted.

Violators can be subject to criminal penalties under 7 U.S.C. 2156 and

18 U.S.C. 49.

b. The mailing of animal-fighting accessories as defined in 461.3 is

prohibited. Violators can be subject to criminal penalties under

U.S.C. 2156.

c. The mailing of animal-fighting matter promoting or furthering an

animal-fighting venture conducted in any state, except for a venture

involving live birds permitted under the laws of the state in which they

are conducted, is nonmailable. See DMM 601.7.5.7.

47 Hazardous, Restricted, and Perishable Mail

120 Publication 52

47 Cigarettes, Smokeless Tobacco, and Electronic

Nicotine Delivery Systems

471 Definitions

471.1 Cigarette

Any roll of tobacco wrapped in paper or in any substance not containing

tobacco, and any roll of tobacco wrapped in any substance containing

tobacco, which because of its appearance, the type of tobacco used in the

filler, or its packaging and labeling, is likely to be offered to, or purchased by,

consumers as a cigarette. The term cigarette includes roll-your-own tobacco

and excludes cigars.

471.2 Smokeless Tobacco

Any finely cut, ground, powdered, or leaf tobacco that is intended to be

placed in the oral or nasal cavity or otherwise consumed without being

combusted.

471.3 Cigar

Any roll of tobacco wrapped in leaf tobacco or in any substance containing

tobacco, unless, because of its appearance, the type of tobacco used in the

filler, or its packaging and labeling, is likely to be offered to, or purchased by,

consumers as a cigarette.

471.4 Roll-Your-Own Tobacco

Any tobacco, which because of its appearance, type, packaging, or labeling,

is suitable for use and likely to be offered to, or purchased by, consumers as

tobacco for making cigarettes or cigars, or for use as wrappers thereof.

471.5 Electronic Nicotine Delivery System (ENDS)

Any electronic device that, through an aerosolized solution, delivers nicotine,

flavor, or any other substance to the user inhaling from the device. ENDS

include but are not limited to the following:

a. Electronic cigarettes (e-cigarettes).

b. Electronic hookahs (e-hookahs).

c. Electronic cigars (e-cigars).

d. Vape pens.

e. Advanced refillable personal vaporizers.

f. Electronic pipes.

Any reference to ENDS includes any component, liquid, part, or accessory of

an ENDS device, regardless of whether the component, liquid, part, or

accessory is sold or provided separately from the device, or regardless of

whether it contains or is used with nicotine.

471.6 Covered Product

For purposes of chapter 47, any cigarette, smokeless tobacco, or ENDS.

Restricted Matter 472.23

September 7, 2023 121

471.7 Consumer Testing

Testing limited to formal data collection and analysis for the specific purpose

of evaluating the product for quality assurance and benchmarking purposes

of cigarette brands or sub-brands among existing adult smokers.

471.8 State

Any of the 50 states of the United States, the District of Columbia, and any

commonwealth, territory, or possession of the United States.

471.9 Minimum Age

The minimum age to send or receive covered products (see 471.6) is

21 years old (the federally required minimum age for the sale or purchase of

covered products), or such higher age that a state or municipality may

impose for the legal sale or purchase of covered products at the place of

acceptance or delivery, as appropriate.

472 Covered Products Generally Nonmailable

472.1 General

The following are nonmailable:

a. Any shipment of covered products described in 473.1.

b. Shipments of covered products that are not described in 473.1 and do

not qualify for an exception under 473.2 through 473.6.

c. Shipments of covered products that are not described in 473.1 and

would generally qualify for an exception under 473.2 through 473.6,

but fail to meet one or more conditions for the applicable exception.

For example, a recipient may fail to be verified as being of at least the

required minimum age (see

473.35a, 473.45a, and 473.55a), or a

Return Receipt may be absent or lack the mailer’s eligibility number

(see

473.33b and 473.53c).

472.2 Treatment of Nonmailable Covered Products

472.21 Refusal of Acceptance and Transmission

The Postal Service will not accept, forward, or deliver any package that it

knows, or has reasonable cause to believe, contains nonmailable covered

products. If the Postal Service reasonably suspects that a mailer is tendering

nonmailable covered products, then the mailer bears the burden of proof in

establishing eligibility to mail.

472.22 Seizure and Forfeiture

Nonmailable covered products deposited in the mail are subject to seizure

and forfeiture. Any nonmailable covered products seized and forfeited will be

destroyed or retained by the federal government for the detection or

prosecution of crimes or related investigations, and then destroyed.

472.23 Disposition of Nonmailable Covered Products Not Seized and

Forfeited

Any nonmailable covered products not seized and forfeited will be handled in

accordance with

216 and 414.

472.24 Hazardous, Restricted, and Perishable Mail

122 Publication 52

472.24 Penalties

Persons involved in the shipment or attempted shipment of nonmailable

covered products may be subject to seizure and forfeiture of assets, criminal

fines, imprisonment, and civil penalties.

472.3 Reasonable Cause to Suspect Covered Products

Among any other potentially relevant circumstances, the Postal Service has

reasonable cause to suspect the presence of covered products based on:

a. A statement on a publicly available website, or an advertisement, by

any person that the person will mail matter which is nonmailable under

this section in return for payment;

b. The fact that the mailer or other person on whose behalf a mailing is

being made is on the U.S. Attorney General’s List of Unregistered or

Noncompliant Delivery Sellers; or

c. Any other characteristics of a package or label, individually or in

combination with other packages or labels, that reasonably indicate

the likely presence of covered products.

472.4 Applicability of Other Laws and Regulations

Shipments permitted under 473 are subject to all other applicable federal,

state, and local laws and regulations. For example, ENDS that consist of or

contain one or more of the following may be subject to prohibitions,

restrictions, or additional requirements stated elsewhere in this publication:

a. Controlled substances (including cannabis and cannabis derivatives).

b. Drug paraphernalia.

c. Lithium batteries.

d. Liquids.

e. Any toxic or flammable substance (e.g., nicotine, diacetyl

[butane-2,3-dione], propanol, and other components of ENDS liquids).

Mailers, recipients, and applicants are solely responsible for complying with

all applicable Postal Service regulations and other federal, state, and local

laws when mailing covered products.

472.5 Recordkeeping

Mailers, recipients, and applicants must maintain records to establish

compliance with the requirements in

473 for a 6-year period and must make

such records available to the Postal Service upon request.

473 Mailability Exceptions

473.1 Scope of Exceptions

Covered products are mailable if one of the conditions in 473.2 through

473.6 is met. These exceptions do not apply to the following:

a. Mail treated as domestic under DMM section 608.2.2.

b. Mail sent to Air/Army Post Office (APO), Fleet Post Office (FPO), or

Diplomatic Post Office (DPO) addresses.

Restricted Matter 473.32

September 7, 2023 123

c. Mail presented at APO, FPO, or DPO installations and destined to

addresses in the United States.

d. International mail as defined in DMM section 608.2.3.

e. Mail presented outside of a face-to-face transaction with a Postal

Service employee at a Postal Service retail or business mail

acceptance location. Examples of prohibited entry methods include,

but are not limited to the following:

(1) Pickup on Demand.

(2) Package pickup.

(3) An Approved Shipper location or other third-party acceptance

location.

(4) A Contract Postal Unit.

(5) A Village Post Office.

(6) Placement in a customer mailbox, collection box, or Postal

Service lobby drop.

473.2 Intra-Alaska and Intra-Hawaii Shipments

Intra-Alaska and intra-Hawaii shipments of covered products are mailable,

provided that such mailings:

a. Are presented in a face-to-face transaction with a Postal Service

employee within the state, and not through any entry method

prohibited under

473.1e;

b. Destinate in the same state of origin;

c. Bear a valid complete return address that is within the state of origin;

and

d. Are marked with the following exterior marking on the address side of

the mailpiece, with the relevant type of item selected: “INTRASTATE

SHIPMENT OF [CIGARETTES/SMOKELESS TOBACCO/ENDS].”

473.3 Exception for Business/Regulatory Purposes

473.31 General

Eligibility to mail and to receive mail under the business/regulatory purposes

exception is limited to federal and state government agencies and legally

operating businesses that have all applicable state and federal government

licenses or permits and are engaged in the manufacturing, distribution,

wholesale, export, import, testing, investigation, or research of covered

products.

Mailings under this exception are permitted only for business purposes

between eligible businesses or for regulatory purposes between such

businesses and eligible government agencies. Mailability is further restricted

to mailings that comply with all conditions in

473.32 through 473.35.

473.32 Application

Each customer seeking to mail covered products under the business/

regulatory purposes exception must submit a complete application

(PS

Form 4615 or 4615-E, as appropriate) and, for ENDS, complete

473.32 Hazardous, Restricted, and Perishable Mail

124 Publication 52

Worksheets 4615-EM and 4615-ER as appropriate, along with all supporting

documentation requested on those forms and worksheets.

The following conditions apply:

a. Along with any other information requested on PS Form 4615 or

4615-E and Worksheets 4615-EM and 4615-ER, the applicant must

furnish the following information:

(1) The applicant’s legal status, copies of any applicable licenses,

and authority under which the applicant operates.

(2) The recipient’s legal status, copies of any applicable licenses,

and operational authority for all recipients to which the mailings

under this exception will be addressed.

(3) All Post Office locations where mail containing covered products

will be presented.

(4) For each business mailer and/or recipient, the nature of the

relevant business activities (e.g., manufacturing, wholesale,

distribution, testing, investigation, import, and export).

(5) The brand name and a description of each product intended to

be mailed. For ENDS, descriptions must include the following

information:

(a) The source of any CBD;

(b) The concentration of any THC; and

documentation for any hazardous materials (e.g., lithium

batteries, nicotine, diacetyl [butane-2,3-dione], or

propanol).

b. The applicant is responsible for establishing the eligibility of each

sender and recipient, and for the accuracy, completeness, and

currency of all information provided in the application. Applications

must be submitted via email to [email protected] as follows:

(1) For cigarettes and smokeless tobacco: PS Form 4615.

(2) For ENDS: PS Form 4615-E and Worksheets 4615-EM and

4615-ER.

c. The director of PCSC will determine eligibility to mail under the

business/regulatory purposes exception. The following applies:

(1) The mailer bears the burden of establishing eligibility and must

furnish any additional supporting documentation requested by

the director of PCSC upon request as necessary.

(2) The director of PCSC may approve or deny an application in its

entirety or only with respect to certain mailers and/or recipients.

(3) A number is assigned to each letter of eligibility.

d. The applicant is responsible for amending the information in its

application, including any updated documentation, in a timely manner,

as necessary, at least 15 days before conducting any mailing to or from

an entity to which the information pertains.

Restricted Matter 473.34

September 7, 2023 125

e. Upon written request by a state or federal agency, the director of

PCSC may, in his or her discretion, waive certain application

requirements for mailings entered by the requesting state or federal

agency for regulatory purposes. The director of PCSC may suspend,

rescind, or modify any waiver at any time.

f. Any determination of eligibility to mail under this exception will lapse if

the authorized mailer does not tender any mail under this exception

within any 3-year period. After that time, the affected mailer must apply

for and receive new authorization for any mailings under this exception.

g. Current lists of authorized mailers will be made available to retail and

business mail acceptance personnel.

473.33 Mailing

All mailings tendered under the business/regulatory purposes exception

must:

a. Be mailed using one of the following combinations of services:

(1) Priority Mail Express with Adult Signature Required or Adult

Signature Restricted Delivery service (see DMM section 503.8.0).

(2) Priority Mail with Adult Signature Required or Adult Signature

Restricted Delivery service.

b. Be accompanied by a Domestic Return Receipt (PS Form 3811). The

sender’s address block must bear the eligibility number issued by the

PCSC and be made returnable to the following address as shown

below:

PCSC, PACT MAILING OFFICE

USPS ELIGIBILITY NO. XX-00-0000

90 CHURCH ST., STE 3100

NEW YORK, NY 10007-2951

c. Bear the following marking, with the relevant type of item and recipient

selected: “[CIGARETTE, SMOKELESS TOBACCO, or ENDS]

MAILING—DELIVER ONLY TO EMPLOYEE OF ADDRESSEE

[BUSINESS or AGENCY] UPON AGE VERIFICATION” on the address

side of the mailpiece.

d. Bear the business or government agency name and full mailing

address of both the sender and recipient. Each must match exactly

those listed on the authorized mailer’s application on file with the

Postal Service.

e. Be entered at a retail and/or business mail acceptance location

specified in the application and authorized by the PCSC.

473.34 Entry and Acceptance

Mailings under the business/regulatory purposes exception must be entered

under the following conditions:

a. Covered products must be tendered via a face-to-face transaction with

a Postal Service employee. Applicable mailings may not be tendered

through any entry method prohibited under

473.1e.

473.35 Hazardous, Restricted, and Perishable Mail

126 Publication 52

b. The mailer must present Postal Service acceptance personnel with the

following:

(1) For shipments of cigarettes and/or smokeless tobacco: A letter

from the PCSC showing that the PCSC has authorized the mailer,

addressee, and acceptance location.

(2) For shipments of ENDS:

(a) A letter from the PCSC showing that the PCSC has

authorized the mailer and has not withheld authorization as

to the addressee;

(b) A PCSC-approved Worksheet 4615-ER showing that the

PCSC has authorized the addressee; and

letter) a PCSC-approved Worksheet 4615-EM showing that

the PCSC has authorized the mailer and the acceptance

location.

c. The Postal Service employee must verify that the mailer, addressee,

and acceptance location match those authorized by the PCSC, based

on the mailer’s documentation and the current list of authorized mailers

available to the Postal Service employee.

473.35 Delivery

Mailings bearing the marking for business/regulatory purposes will only be

delivered to a verified employee of the addressee business or government

agency under the following conditions:

a. The recipient must be an adult of at least the required minimum age

(see

471.9) at the place of delivery. A Postal Service employee must

verify the recipient’s age before releasing or delivering the item to the

recipient. The recipient must furnish proof of age via a driver’s license,

passport, or other government-issued photo identification that lists age

or date of birth.

b. The recipient must demonstrate status as an employee of the business

or government agency identified as the addressee on the mailing label.

Proof of employment may take the form of one or more of the

following:

(1) An employee identification badge or card issued by the employer

and including the following:

(a) Employee’s name.

(b) Employer’s name.

(2) A signed letter on company or agency letterhead from a

supervisor or human relations office attesting to the recipient’s

current employment.

(3) Where delivery is made to a business address, employment

status may be inferred from the carrier’s observation of such

factors as the recipient’s uniform and presence at a reception

desk or retail counter.

Restricted Matter 473.43

September 7, 2023 127

(4) Any other form of identification that the postmaster deems to be

of comparable reliability.

c. Once the recipient’s age and identity as an employee of the addressee

are verified, the recipient must sign for receipt of delivery and in the

appropriate signature block of PS Form 3811.

473.4 Exception for Certain Individuals

473.41 General

The exception for certain individuals permits the mailing of small quantities of

covered products by individual adults for noncommercial purposes.

Mailability is further restricted to mailings that comply with all conditions in

473.42 through 473.45. Eligible shipments may be made to any type of

recipient (individual, business, government, or other organization).

473.42 Noncommercial Purposes

Noncommercial purposes may include, but are not limited to, the following:

a. Covered products exchanged as gifts between individual adults. For

purposes of this rule, “gifts” do not include covered products that one

individual purchased for another from a third-party vendor through a

mail-order transaction, or covered products included at no additional

charge with other matter in accordance with a commercial transaction.

b. Damaged or unacceptable covered products that a consumer returned

to the manufacturer or other business. The manufacturer or other

business may provide the consumer with a refund, credit, replacement

product, or other form of value in exchange for the damaged or

unacceptable covered product, as long as it does not exceed the

amount that the consumer paid for the damaged or unacceptable

product plus the cost of return shipping for the damaged or

unacceptable product.

c. Used covered products sent by a consumer to a manufacturer or other

business for recycling. For purposes of this rule, the consumer must

not receive anything of value (e.g., a discount, credit, or rebate) in

exchange for a returned item.

473.43 Mailing

No customer may send or cause to be sent more than 10 mailings under this

exception in any 30-day period. Each mailing under the certain-individuals

exception must:

a. Weigh no more than 10 ounces.

b. Be mailed using one of the following combinations of services:

(1) Priority Mail Express with Adult Signature Required or Adult

Signature Restricted Delivery service (see DMM section 503.8.0).

(2) Priority Mail with Adult Signature Required or Adult Signature

Restricted Delivery service.

c. The Priority Mail Express or Priority Mail label must bear the full name

and mailing address of the sender and recipient.

473.44 Hazardous, Restricted, and Perishable Mail

128 Publication 52

d. Bear the following exterior marking on the address side of the

mailpiece, with the relevant type of item selected: “PERMITTED

[CIGARETTE/ SMOKELESS TOBACCO/ ENDS] MAILING—DELIVER

ONLY UPON AGE VERIFICATION.”

473.44 Entry and Acceptance

Mailings under the certain-individuals exception must be entered under the

following conditions:

a. Covered products must be tendered via a face-to-face transaction with

a Postal Service employee. Applicable mailings may not be tendered

through any entry method prohibited under

473.1e.

b. The individual presenting the mailing must furnish a driver’s license,

passport, or other government-issued photo identification that lists age

or date of birth. The following also applies:

(1) The name on the identification must match the name of the

sender appearing in the return address block of the mailpiece.

(2) The customer must be an adult of at least the required minimum

age at the place of acceptance (see

471.9).

c. For mailings addressed to an individual, at the time the mailing is

presented the customer must orally confirm that the addressee is an

adult of at least the required minimum age at the place of delivery

(see

471.9).

473.45 Delivery

Delivery under the certain-individuals exception is made under the following

conditions:

a. The recipient receiving or signing for the article must be an adult of at

least the required minimum age at the place of delivery (see

471.9).

Postal Service employees must confirm this before releasing or

delivering the item to the recipient. The recipient must furnish proof of

age via a driver’s license, passport, or other government-issued photo

identification that lists age or date of birth.

b. Once the recipient’s age is verified, the recipient must sign for receipt

of delivery.

473.5 Consumer-Testing Exception

473.51 General

The consumer-testing exception permits a legally operating cigarette

manufacturer or a legally authorized agent of a legally operating cigarette

manufacturer to mail cigarettes to verified adult smokers solely for consumer

testing purposes. The manufacturer for which mailings are entered under this

exception must have a permit, in good standing, issued under 26 U.S.C.

5713. The consumer-testing exception applies only to cigarettes and not to

smokeless tobacco or ENDS. Mailability is further restricted to mailings that

comply with all conditions in

473.52 through 473.55.

Restricted Matter 473.52

September 7, 2023 129

473.52 Application

Each person seeking to mail cigarettes under the consumer-testing

exception must email a complete application (PS Form 4616), along with all

supporting documentation requested on that form, to [email protected]v. For

each application, the following conditions must be met:

a. The applicant must furnish the following information:

(1) A copy of the relevant manufacturer’s permit issued under 26

U.S.C. § 5713.

(2) If the applicant is an agent of a manufacturer, complete details

about the agency relationship with the manufacturer.

(3) All locations where mail containing cigarettes for consumer

testing will be presented.

b. As part of the application, the applicant must certify in writing that it will

comply with the following requirements:

(1) Any recipient of consumer-testing samples of cigarettes is an

adult established smoker.

(2) No recipient has made any payment for the cigarettes.

(3) Every recipient will sign a statement indicating that the recipient

wishes to receive the mailings.

(4) The manufacturer or the legally authorized agent of the

manufacturer will offer the opportunity for any recipient to

withdraw the recipient’s written statement at least once in every

3-month period.

(5) Any package mailed under this exception will contain no more

than 12 packs of cigarettes (maximum of 240 cigarettes) on

which all taxes levied on the cigarettes by the state and locality of

delivery have been paid, and all related state tax stamps or other

tax-payment indicia have been applied.

c. The application must be emailed to the director, PCSC, at

[email protected]. The applicant bears the burden of establishing

eligibility.

d. The applicant must provide any requested copies of records

establishing compliance to the director, PCSC, and/or the director,

Product Classification (see

214 for address), no later than 10 business

days after the date of the request.

e. The director, PCSC, will determine eligibility to mail under the

consumer-testing exception. The following applies:

(1) The director, PCSC, may approve or deny an application in its

entirety or only with respect to certain mailers and/or recipients.

(2) A number is assigned to each letter of eligibility.

f. For as long as the applicant or authorized mailer continues to mail

under the consumer-testing exception, the applicant or authorized

mailer must update the information in the application with the director,

PCSC, as necessary, in a timely manner upon becoming aware of a

change in application information. The information must be updated no

later than 15 days before conducting any mailing.

473.53 Hazardous, Restricted, and Perishable Mail

130 Publication 52

g. Any determination of eligibility to mail under this exception will lapse if

the authorized mailer does not tender any mail under this exception

within any 3-year period. After that time, the mailer must apply for and

receive new authorization for any further mailings under this exception.

h. Current lists of authorized mailers will be made available to retail and

business mail acceptance personnel.

473.53 Mailing

All mailings under the consumer-testing exception must meet the following

provisions or conditions:

a. Be limited in tobacco content to no more than 12 packs of cigarettes

(maximum 240 cigarettes) on which all taxes levied on the cigarettes by

the destination state and locality have been paid, and all related state

tax stamps or other tax-payment indicia have been applied.

b. Be mailed using one of the following combinations of services:

(1) Priority Mail Express with Adult Signature Restricted Delivery

service (see DMM section 503.8.0).

(2) Priority Mail with Adult Signature Restricted Delivery service.

c. Be accompanied by a Domestic Return Receipt (PS Form 3811). The

sender’s address block must bear the eligibility number issued by the

PCSC and be made returnable to the following address as shown

below:

PCSC, PACT MAILING OFFICE

USPS ELIGIBILITY NO. XX-00-0000

90 CHURCH ST., STE 3100

NEW YORK, NY 10007-2951

d. Bear the following marking: “PERMITTED CIGARETTE MAILING—

DELIVER ONLY TO ADDRESSEE UPON AGE VERIFICATION” on the

address side of the mailpiece.

e. Bear the name and full mailing address of both the mailer and recipient.

Each must match exactly those listed on the authorized mailer’s

application on file with the Postal Service.

f. Not be addressed to an addressee located in a state that prohibits

delivery or shipment of cigarettes to individuals in the destination state.

g. Be sent only to an addressee who meets the following requirements:

(1) Has not made any payment for the cigarettes.

(2) Is being paid a fee for participation in consumer tests.

(3) Has agreed to evaluate the cigarettes and furnish feedback to the

manufacturer in connection with the consumer test.

h. Not exceed more than one package from any one manufacturer to an

adult smoker during any 30-day period.

i. Be entered at a retail and/or business mail acceptance location

specified in the application and authorized by the PCSC.

Restricted Matter 473.6

September 7, 2023 131

473.54 Entry and Acceptance

Mailings under the consumer-testing exception must be entered under the

following conditions:

a. Covered products must be tendered via a face-to-face transaction with

a Postal Service employee. Applicable mailings may not be tendered

through any entry method prohibited under

473.1e.

b. The mailer must present Postal Service acceptance personnel with a

letter from the PCSC showing that the PCSC has authorized the mailer,

addressee, and acceptance location.

c. The Postal Service employee must verify that the mailer, addressee,

and acceptance location match those authorized by the PCSC, based

on the mailer’s documentation and the current list of authorized mailers

available to the employee.

473.55 Delivery

Mailings bearing the marking for consumer testing will only be delivered to

the named addressee under the following conditions:

a. The recipient signing for the article must be an adult at least 21 years

old. The following requirements also must be met:

(1) A Postal Service employee must verify the recipient’s age before

releasing or delivering the item to the recipient.

(2) The recipient must furnish proof of age via a driver’s license,

passport, or other government-issued photo identification that

lists age or date of birth.

(3) The name on the identification must match the name of the

addressee on the Priority Mail Express or Priority Mail label.

b. Once the recipient’s age and identity are verified, the recipient must

sign for receipt of delivery and in the appropriate signature block of

Form 3811.

473.6 Public Health Exception

Federal government agencies involved in the consumer testing of tobacco

products solely for public health purposes may mail cigarettes (this does not

apply to smokeless tobacco or ENDS) under the mailing standards of

473.5,

except as follows:

a. The federal agency is not required to have a manufacturer’s permit

issued under 26 U.S.C. § 5713.

b. The recipient is not required to be paid a fee for participation in

consumer tests.

Upon written request, the director, PCSC, may waive certain application

requirements for mailings entered by the requesting federal agency. The

director, PCSC, may suspend, rescind, or modify any waiver at any time.

473.7 Hazardous, Restricted, and Perishable Mail

132 Publication 52

473.7 Suspension or Revocation of Eligibility

Eligibility to mail under one of the exceptions in 473.2 through 473.6 may be

suspended or revoked by the director, PCSC, in the event of failure to

comply with any applicable law or regulation. The following applies to

suspensions or revocations:

a. A customer may appeal an adverse initial decision to the director,

Product Classification (see

214 for address).

b. The mailer bears the burden of proof in establishing eligibility in any

appeal of a suspension or revocation decision and of furnishing all

supporting documentation when requested.

c. Decisions by the director, Product Classification, to revoke a

customer’s eligibility under any exception may be appealed to the

Judicial Officer under 39 CFR Part 953.

474 Additional Guidance

474.1 Interpretative Guidance

The definitions in 471.1 through 471.5 and the exclusion in 474.2 are in

accordance with section 1 of the Jenkins Act (15 U.S.C. § 375), which is

administered by the Bureau of Alcohol, Tobacco, Firearms, and Explosives

(ATF). Interpretative guidance regarding these provisions may be requested

by contacting ATF at the following address, with a copy to the PCSC

(see

213 for address):

BUREAU OF ALCOHOL, TOBACCO, FIREARMS AND EXPLOSIVES

99 NEW YORK AVENUE NE

c/o 90 K ST. NE, STE. 250

WASHINGTON, DC 20226

474.2 Exclusion of Products Approved for Tobacco Cessation or

Therapeutic Purposes

A product is excluded from the definition of ENDS in 471.5 (15 U.S.C. §

375(7)(C)) if:

a. It is approved by the Food and Drug Administration for sale as a

tobacco-cessation product or any other therapeutic purpose; and

b. Is marketed and sold solely for such purposes.

Any party who believes that a product to be sent through the mail qualifies

for this exclusion should provide appropriate documentation to ATF at the

address in

474.1, with a copy to the PCSC.

September 7, 2023 133

5 Perishable Matter

51 Definition

511 General Definitions

Perishable matter is anything that can deteriorate in the mail and thereby lose

value, create a health hazard, or cause an obnoxious odor, nuisance, or

disturbance, under ordinary mailing conditions. Mailable perishable matter

may be sent at the mailer’s own risk when it is packaged as required and

when it can be delivered within appropriate and reasonable time limits to

prevent deterioration.

Examples of perishable matter include mailable types of live animals, food

items, and plants.

512 Federal Statutes

Federal statutes impose restrictions and prohibitions on the mailing of fish,

wildlife, plants, and products made from these, as well as plant pests,

injurious animals, and taken fish, wildlife, and plants. The purpose of these

restrictions and prohibitions is to protect agriculture, ecosystems, and

natural resources in the United States. Additional information on these

restrictions and prohibitions can be found in the Lacey Act and in the

Endangered Species Act, U.S. Fish & Wildlife Service, the Animal Welfare

Act, and the Plant Protection Act under the U.S. Department of Agriculture.

52 Animals

521 General Requirements

The full cooperation of the mailer is essential in order to safely and effectively

transport animals through the mail. The following factors are applied to all

shipments of mailable live or dead animals:

a. Protection of Postal Service employees and the public against harm

from dangerous or diseased animals.

b. Protection of the mail and the environment against the following:

(1) Damage to the shipping container or other mailpieces from either

the animal or the refrigerant used (e.g., moisture or condensation

from melting ice, or pressure build-up from dry ice).

(2) Obnoxious odors and noise.

522 Hazardous, Restricted, and Perishable Mail

134 Publication 52

c. Protection of animals against death, or protection of animal specimens

against spoilage, taking into account the following:

(1) Expected time in transit.

(2) Expected temperature in transit (weather conditions).

(3) Packaging, including insulation against impact, heat, cold, and

preventing suffocation.

d. Ability of an animal to survive without food or water during transport.

Live animals must be transported without food or water, because liquids,

moisture, and loose foodstuffs can cause damage to the shipping

container, other mail, and Postal Service equipment during transport.

e. The ability of the Postal Service to provide transportation and delivery

service. Mailers are urged to work with postmasters in providing

advance notification of shipments of live animals. The Postal Service

advises destination and transfer offices when any significant quantities

of animals are moving in the mail. Postal Service field personnel should

consider a 4-hour time limit on the period during which animals

(especially bees, day-old poultry, and adult birds) may move in a

regular, closed Postal Service vehicle.

522 Packaging and Markings

522.1 Container Construction

Any container used to mail perishable matter must be constructed to protect

and securely contain the contents.

Shipping containers for mailable live animals must, at a minimum, be made

of 275-pound test, double-wall, corrugated, weather-resistant fiberboard

(W5c) or equivalent. USPS-produced packaging, including Flat Rate

containers, are not eligible to be used. Additional container requirements

apply to mailable adult birds.

522.2 Security and Ventilation

Containers must be constructed to prevent escape of animals, prevent the

crushing of the container and contents during normal handling, and provide

adequate ventilation for the animals at all times.

522.3 Marking

Each mailpiece must bear a complete return address and be marked on the

address side with a description of the contents (e.g., “Live Animals,” “Live

Honey Bees,” etc.). A mailpiece marked “If Undeliverable, Abandon” may not

be accepted for mailing.

523 Acceptance for Mailing

A mailpiece containing live animals that cannot reach its destination in a

viable condition should not be accepted. Factors that can be taken into

consideration in assessing the viability of a mailpiece containing live animals

include: use of proper packaging methods that protect against suffocation

and crushing during transport; expected time in transit; and extreme weather

conditions that exceed the normal weather pattern along the transportation

route.

Perishable Matter 525.3

September 7, 2023 135

This provision does not give Postal Service personnel the authority to refuse

mailable animals that are properly packaged or to impose local black-out

periods based on temperature conditions, heavy mail volumes, etc.

Acceptance personnel must have reasonable justification to refuse a

mailpiece. Before refusing any mailpiece that contains a mailable type of

animal, acceptance personnel are to confer with the manager, business mail

entry, at their district office or with the PCSC, as appropriate.

Animals mailed to the Republic of Palau, the Republic of the Marshall

Islands, and the Federated States of Micronesia require a permit issued by

the government of the destination country. See

642.

524 Disposal

Any mailpiece containing live animals that cannot be delivered to the

addressee or returned to the sender within 72 hours (for live, day-old poultry)

or within the delivery period marked on the parcel (for other mailable animals)

must be disposed of immediately. For safety reasons, dispose of mailpieces

not marked with a delivery period when it reasonably appears the articles

cannot be delivered or returned in a viable condition. See POM 691.52 for

disposal information. Also see

742.3 for the disposition of mailpieces that are

refused by air carriers.

525 Nonmailable Live Animals

Nonmailable types of animals discovered in the mailstream must be reported

to the PCSC in accordance with the instructions in POM 139.118.

Additionally, the mailer and the Post Office of mailing must be notified to

prevent future shipments from being incorrectly accepted for mailing.

525.1 Live Birds

Day-old poultry vaccinated with Newcastle disease (live virus) is nonmailable.

Day-old birds, except those specifically permitted under

526.3 are

nonmailable.

525.2 Live, Warm-Blooded Animals

Warm-blooded animals, except for adult birds and specified day-old birds

under the specific conditions in this section, are not mailable.

a. Cats or kittens.

b. Dogs or puppies.

c. Guinea pigs.

d. Hamsters.

e. Mice.

f. Rabbits.

g. Rats.

h. Squirrels and flying squirrels.

525.3 Reptiles

All snakes, turtles, and poisonous reptiles are nonmailable.

525.4 Hazardous, Restricted, and Perishable Mail

136 Publication 52

525.4 Poisonous Insects and Spiders

All poisonous insects and all spiders, except scorpions under limited

circumstances (see

526.5), are nonmailable. Other nonpoisonous and non-

disease-conveying insects are permitted as stated in Exhibit 526.6.

526 Mailable Live Animals

526.1 General

Some animals are mailable under proper conditions. See the specific

instructions as noted for the following kinds of animals:

a. Live bees, 526.2 and Exhibit 526.21.

b. Live, day-old poultry, 526.3 and Exhibit 526.33.

c. Live adult birds, 526.4.

d. Live scorpions (only under limited circumstances), 526.5 and Exhibit

526.5.

e. Other small, harmless, cold-blooded animals, 526.6 and Exhibit 526.6.

Note: Regarding dead animals or parts of animals, see 526.7

and Exhibit 526.7.

526.2 Live Bees

526.21 Mailability Requirements

Honeybees and queen honeybees must be free of disease, as required under

federal and state regulations. The following additional conditions apply:

a. Honeybees. Honeybees are acceptable to mail only via surface

transportation. (See b. for exception.) Mailpieces must be plainly

marked on the address side with “Live Bees” and “Surface Only” or

“Surface Mail Only.”

b. Queen Honeybees. Queen honeybees may be shipped via air or

surface transportation. Each mailpiece shipped via air transportation is

limited to one queen and eight or less attendant honeybees.

All mailpieces containing queen honeybees must be plainly marked on the

address side with “Live Queen Bees.” Refer to

Exhibit 526.21 for a general

summary of the requirements for mailing live bees.

Exhibit 526.21

Requirements for Mailing Live Bees

Live Bees

Contents must be either queen honeybees or honeybees.

Bees must be securely packaged (see 522) to provide

adequate air and they must be kept within a tolerable

temperature range at 40° to 100° F.

The use of insecticides must be eliminated in Postal

Service

areas that will be occupied by bee shipments.

Air Transportation Surface Transportation

 Only queen honeybees may be

shipped by air transportation.

 Each queen honeybee may be

accompanied by up to eight

attendant honeybees.

 Alert personnel to ensure the queen

honeybees’ timely and safe dispatch

to, and arrival at, the destination.

 Equipment must be available for

transportation up to the 4th zone.

Advance arrangements must be

made for shipment to addresses

beyond the 4th zone.

 Any type of live honeybees may be

shipped in the continental United

States by surface transportation.

 Alert personnel to ensure the

honeybees’ timely and safe dispatch

to, and arrival at, the destination.

 Equipment must be available for

transportation up to the 4th zone.

Advance arrangement must be made

for shipment beyond the 4th zone.

Perishable Matter 526.32

September 7, 2023 137

526.22 Claims for Bee Shipments

Indemnity claims (see DMM 609) for damage, partial loss, and loss of insured

shipments of mailable bees are accepted only in the following situations:

a. Death of the bees resulted from Postal Service handling after

conditions

for mailability were met and when there was strong

likelihood that the shipment could have been safely transported.

b. Contents were lost because of damage to the container while in Postal

rvice custody.

c. The complete package was lost in the mail.

526.3 Live, Day-Old Poultry

526.31 General

The following live, day-old animals are acceptable for mailing when properly

packaged: chickens, ducks, emus, geese, guinea birds, partridges,

pheasants (only during April through August), quail, and turkeys. All other

types of live, day-old poultry are nonmailable. Day-old poultry vaccinated

with Newcastle disease (live virus) also is nonmailable.

526.32 Mailability Requirements

The specific types of day-old poultry named in 526.31 are mailable subject to

the following requirements:

a. Poultry that is not more than 24 hours

old and is presented for mailing

in the original, unopened hatchery box from the hatchery of origin.

b. The date and hour of hatching is not

ed on the box by a representative

of the hatchery who has personal knowledge thereof. (For Collect on

Delivery (COD) shipments made by a hatchery for the account of

526.33 Hazardous, Restricted, and Perishable Mail

138 Publication 52

others, the name or initials and address of the hatchery or the Post

Office box number and address of the hatchery must be prominently

shown for this standard.)

c. Box is properly ventilated, of proper construction and strength to bear

safe transport in the mail, and is not stacked more than 10 units high.

d. Day-old poultry is mailed early enough in the week to avoid receipt at

the office of address (in case of missed connections) on a Sunday, a

national holiday, or the afternoon before a Sunday or national holiday.

e. Day-old poultry can be delivered to the addressee within 72 hours of

the time of hatching.

f. Day-old poultry sent via air transportation must meet all provisions of

the airlines. Delivery of the mailpiece is dependent on the availability of

air carriers having available equipment to safely deliver the day-old

poultry within the specified time limit.

g. Day-old poultry that is first shipped via a commercial air express or air

cargo service and then presented for mailing to a final destination must

be in good condition and properly packaged as specified in

526.32a-e.

h. Boxes of day-old poultry of about identical size, securely fastened

together to prevent separation in transit, may be accepted for mailing

as a single parcel, provided the total length and girth combined does

not exceed Postal Service limits.

See Exhibit 526.33, Requirements for Mailing Live, Day-Old Poultry. See

Chapter 7 regarding domestic mail shipments sent via air transportation.

526.33 Claims for Live, Day-Old Poultry

Indemnity claims (see DMM 609) for damage, partial loss, and loss of insured

shipments of mailable, live, day-old poultry are accepted only in the following

situations:

a. Death of the live, day-old poultry resulted from Postal Service handling

after conditions for mailability were met and when there was strong

likelihood that the shipment could have been safely transported.

b. Contents were lost because of damage to the container while in Postal

Service custody.

c. The complete package was lost in the mail.

Exhibit 526.33

Requirements for Mailing Live, Day-Old Poultry

Answer each question and follow the instruction

as indicated. YES NO

1. Is poultry live, day-old poultry as listed in

526.31?

If pheasants, they are

mailable only during April

through August.

See No. 2.

If not day-old poultry, item is

NMAILABLE. If not

poultry or not day-old, check

other mailable animal types

in Section

52 to determine

mailability.

2. Was hatching time 24 hours ago or less? See No. 3. NONMAILABLE.

3. Was poultry presented for mailing in

original, unopened hatchery

box from

hatchery of origin?

See No. 4. Do not accept.

4. Are boxes properly ventilated and of proper

construction and strength to bear safe

transport in mail?

Note: Boxes of appr

oximately identical size,

securely fastened to prevent separation in

transit, may be accepted for mailing as a

single parcel if the mailpiece does not

exceed DMM limits for combined length and

girth or exceed 70 pounds in weight.

Boxes are not to be

stacked more than

10 units high.

See No. 5.

Do not accept.

5. Are the date and hour of hatching noted on

ox by representative of hatchery who has

personal knowledge of facts?

See No. 6. Do not accept.

6. Did shipment originate at another office, or

was it sent by air express or air cargo and

then presented for mailing?

Before accepting, take

special precautions to

ensure that shipment is in

excellent condition.

See No. 7.

7. If shipment is COD, have all conditions for

using COD service (as required in

DMM

503.11) been met? If not COD, see

No. 8.

See No. 8. If COD, do not accept unless

all applicable requirements in

DMM 503.11 are met.

8. Is poultry being mailed sufficiently early in

week to avoid arrival at the

delivery post

office on Sunday or holiday, or on afternoon

preceding Sunday or holiday?

See No. 9. Do not accept.

9. Can poultry be delivered to addressee

within 72 hours of time of hatching,

regardless of whether addressee resides in

town or on rural or highway contract route?

Accept for mailing. Do not accept.

Perishable Matter 526.33

September 7, 2023 139

526.4 Hazardous, Restricted, and Perishable Mail

140 Publication 52

526.4 Adult Birds

526.41 General

Mailers must be in compliance and may ship disease-free adult birds

domestically under all applicable governmental laws and regulations,

including the Lacey Act, the Endangered Species Act (ESA), the Animal

Welfare Act, regulations of the U.S. Department of Agriculture, U.S. Fish and

Wildlife Service, and any state, municipal, or local ordinances. Mailings must

also be compliant with the requirements provided in USPS Publication 14,

Prohibitions and Restrictions on Mailing Animals, Plants, and Related Matter,

Chapter 5. In addition, each container or package must be marked as

required by U.S. Fish and Wildlife Service under 50 CFR 14. Adult birds must

be properly packaged and able to sustain shipment without food or water

because liquids, moisture, and loose foodstuffs can cause damage to the

shipping container, other mail, and Postal Service equipment during

transport.

526.42 Mailability Requirements

Adult birds are mailable only when sent under the following conditions:

a. The shipment is mailed using Priority Mail Express service.

b. Each bird must weigh more than 6 ounces and no more than

pounds.

c. The number of birds per parcel must follow the container manufacturer

limits.

d. The mailer must use containers that the director, Product

Classification, has approved.

e. If the mailer is unable to secure a previously approved container, the

mailer must submit the proposed container for approval to the director,

Product Classification (see part

214 for address). Upon submission,

valid written evidence of a test conducted by a competent authority

using a full container of live birds throughout a 3-day period of the

challenge must be provided. The test must satisfy the following:

(1) Confining live birds in the container must neither endanger the

health of the birds nor subject them to inhumane treatment.

(2) Environmental temperatures as high as 99 degrees Fahrenheit,

and as low as 0 degrees Fahrenheit or lower for extended

periods, must pose no greater physiological stress on birds

confined in the container than on birds in containers with

conventional ventilation.

(3) The container design must include a low level of light and no

visual stimuli in order to reduce the birds’ awareness of being

moved or sense of alarm due to the presence of humans or other

animals nearby, reducing the birds’ psychological stress.

f. The mailer must meet the requirements in Packaging Instruction 10D of

Appendix C.

Perishable Matter 526.6

September 7, 2023 141

526.43 Claims for Adult Birds

Indemnity may be paid only for articles that are lost, damaged, or for missing

contents, and not for death of the birds in transit if there is no visible damage

to the mailing container.

The Postal Service will not refund postage if the Priority M

ail Express

shipment was delivered, or delivery was attempted, within three days of the

date of mailing shown in the “Date In” box on Label 11. See DMM 604.9.5.5.

526.5 Live Scorpions

The mailing of scorpions is limited by the restrictions in 18 U.S.C. 1716.

Under this limitation, scorpions are mailable only when sent for the purposes

of medical research use or the manufacture of antivenin. Scorpions are

nonmailable under any other circumstances. See

Exhibit 526.5 for mailing

conditions that apply to permissible

shipments.

Exhibit 526.5

Restrictions on Mailing Live Scorpions

Live scorpions are mailable only if EACH of the following conditions is met:

1. Must be for delivery only within the contin

ental United States.

2. May be sent only by surface transportation.

3. Must be sent only for spec

ial purposes of either:

 Medical research use.

 Manufacture of antivenin.

4. Must be properly packaged prior to

mailing, as follows:

 Live scorpions is packed in a double container system, with each

receptacle closed or fastened in such a way as to prevent escape.

 Inner receptacle is made of material that cannot be punctured by a

scorpion.

 Inner receptacle is marked “Live Scorpions.”

 Cushioning material is used to prevent shifting of the inner receptacle.

 Design of packaging is of sufficient strength, as required in 522, to prevent

crushing of the mailpiece or escape of

the contents during normal Postal

Service handling and transport.

 Address side of mailpiece is clearly marked “Live Scorpions.”

526.6

Small, Harmless, Cold-Blooded Animals

Small, harmless, cold-blooded animals, except for snakes, turtles, and turtle

eggs, are mailable only when they meet certain requirements. For some

examples, see

Exhibit 526.6.

Exhibit 526.6

Requirements for Mailing Small, Harmless, Cold-Blooded Animals

(Except Snakes, Turtles, and Turtle Eggs)

General Requirements:

All animals in this group:

 Must be able to reach their destination in good condition in the normal transit

time between the mailing and address points.

 Must not require any food, water (except for fish), or attention during transport.

 Must not create sanitary problems.

 Must not create obnoxious odors.

Specific Requirements by Animal:

Baby Alligators

Baby Caimans

Chameleons

Frogs

Lizards

Newts

Reptiles and Amphibians

Salamanders

Tadpoles and Toads

 Animals must not exceed 20 inches in length.

 No additional requirements, except the applicable

standards in section

52.

 Packaging must comply with 522.

Specific Requirements by Animal:

Goldfish

Tropical Fish

 Fish must be held in a securely sealed primary

receptacle.

 Primary receptacle must be cushioned with

sufficient absorbent material to take up all liquid

in case of leakage.

 Primary receptacle and absorbent cushioning

material must be sealed within waterproof outer

(shipping) packaging.

Worms

Bloodworms

Hellgrammites

Leeches

Mealworms

Snails

 No additional requirements, except the applicable

standards in section

52.

 Packaging must comply with 522.

Nonpoisonous Insects

 No additional requirements, except the applicable

standards in section

52.

 Packaging must comply with 522.

526.7 Hazardous, Restricted, and Perishable Mail

142 Publication 52

526.7 Dead Animals or Parts of Animals

The dead bodies, or parts thereof, of any wild animals, wild birds, or eggs are

acceptable for mailing only when they are lawfully killed or taken, and their

shipment is not prohibited by law of the United States or of the state,

territory, district, or foreign country or subdivision thereof in which killed or

taken or offered for shipment. Mailing of fresh game is also subject to these

standards. Dead animals or parts of animals include two groups of items:

a. Group A: Items that need to be refrigerated.

b. Group B: Items that must be dried.

See

Exhibit 526.7 for additional information on the conditions for mailing.

Exhibit 526.7

Requirements for Mailing Dead Animals or Parts of Animals

GROUP A: Items that need to be refrigerated

Game birds, fish, or other

imals to be used for

food.

Animals or animal parts to

be used in conservation

studies or to be preserved

by taxidermy.

Mailable only when:

 Overall requirements for animals (see 521) are

met.

 A proper refrigerant is used as follows:

– Water ice. When water ice is used as a

refrigerant

, it must be packed like a liquid in a

sealed, waterproof primary receptacle. The

primary receptacle must be surrounded by

absorbent cushioning material in a quantity

sufficient to take up all water in the event of

leakage. The primary receptacle and

cushioning material must be securely packed

within an outer (shipping) packaging.

– Dry ice. When dry ice is used, it must be

ckaged as required in

349.23. It must

NEVER be placed in a sealed container. In

addition, sufficient cushioning material must

be used so that an inner container will not

become loose inside the shipping container

as the dry ice sublimates.

 Salt. The use of salt to retard spoilage can be

effective.

 The mailpiece is properly addressed and marked

as required under 221 and DMM 102.

GROUP B: Items that must be dried

Dried furs, hides, skins, or

pel

ts of wild animals.

Mailable only when such articles:

 Are properly dried or cured.

 Have no offensive odor.

 Are plainly marked and/or labeled on the

address side with the full names and addresses

of shipper and addressee, together with such

endorsement(s) as may be required by state

laws.

 Are securely packaged and/or wrapped to

prevent harm to Postal Service employees and

damage to the package contents or postal

equipment.

Perishable Matter 53

September 7, 2023 143

53 Fresh Foods and Other Perishables

Fresh fruits and vegetables are nonmailable unless presented in a dry (not

dried) condition. Other perishable foods that are capable of easily

decomposing or that cannot reach their destination without spoiling are

nonmailable. Packaging must be strong and securely sealed as required in

DMM 601.1-7.

54 Hazardous, Restricted, and Perishable Mail

144 Publication 52

54 Eggs

Eggs are mailable in domestic mail subject to the following general

conditions:

a. They are individually cushioned.

b. They are otherwise packed to withstand shocks encountered during

normal Postal Service handling.

c. They are not likely to be harmed by anticipated temperature changes

while in Postal Service custody.

55 Meats and Meat Products

Meats and meat products are mailable in domestic mail only when they

conform to regulations of the U.S. Department of Agriculture (USDA).

Packaging must be strong and securely sealed as required in DMM 601.1-7.

If dry ice is used to cool meat or meat products during transport, the dry ice

is subject to the mailing conditions in

349.23.

56 Plants

561 General

Plants and plant products are mailable within the United States and its

territories and possessions, but are subject to certain prohibitions and

restrictions imposed by federal agricultural and conservation statutes. When

these prohibitions and restrictions render the shipment of any plant or plant

product as unlawful, then those plants are nonmailable. For more

information, see Publication 14, Prohibitions and Restrictions on Mailing

Animals, Plants, and Related Matter.

562 Quarantines

Under 39 U.S.C. 3014(b), any plant, plant product, or other article capable of

carrying a dangerous plant disease or insect infestation is nonmailable from a

quarantined area, if shipping such an item is prohibited by the U.S.

Department of Agriculture (USDA) Plant Protection Act issued under 7 U.S.C.

7701. The USDA imposes such quarantines on specific plants to prevent the

introduction of agricultural diseases or pests into the United States and to

prevent their spread from one part of the United States to another.

USDA quarantine notices, issued under 7 U.S.C. 7701, are published in the

Federal Register and codified in 7 CFR (e.g., 7 CFR 301 and 318). Details on

these and other USDA regulations may be obtained by writing to the USDA

Animal and Plant Health Inspection Service (APHIS) Plant Protection and

Quarantine (PPQ) Programs (see

564 for address).

Perishable Matter 563.1

September 7, 2023 145

562.1 Types of Quarantines

There are domestic quarantines that apply to the continental United States;

other quarantines that apply to Hawaii, Puerto Rico, and the U.S. Virgin

Islands; and others that apply to other territories and possessions.

Any plant or plant matter prohibited under the Act of August 20, 1912

(37

Stat. 315, Chapter 308; 7 U.S.C. 151 et seq.), commonly known as the

Plant Protection Act, is made nonmailable by 39 U.S.C. 3015©.

562.2 Specific Information

Plant quarantines cover a great variety of plant diseases and pests, and all

areas of the country. For more specific information, consult Publication 14,

Prohibitions and Restrictions on Mailing Animals, Plants, and Related Matter.

562.3 Inspection

Plants under quarantine by the USDA may be moved from the quarantine

area only after being inspected under conditions prescribed in the quarantine

notice or in other USDA regulations, issued under 7 U.S.C. 7701, and after a

permit or certificate is issued. Refer to ASM 274.9 regarding USDA

inspection of mail.

562.4 Penalties

562.41 Nonmailable Items

Criminal penalties of fine and imprisonment are provided for mailing

nonmailable items as follows:

a. Under 18 U.S.C. 1716B, for anyone who knowingly mails, or causes to

be delivered by mail, anything nonmailable pursuant to

U.S.C. 3014(b) and the regulations implementing 39 U.S.C. 3014(c).

b. Under 18 U.S.C. 1716D, for anyone who knowingly mails, or causes to

be delivered by mail, anything nonmailable pursuant to

U.S.C. 3015(c).

562.42 Forged or Counterfeit Documents

Similar criminal penalties of fine and imprisonment are provided by

U.S.C. 1716C as follows:

a. For anyone who forges or counterfeits any certification authorized by

USDA regulations with intent to make such certification appear

genuine.

b. For anyone who makes or knowingly uses, sells, or possesses with

intent to use or sell, any such forged or counterfeited certification or

any device for imprinting a forged or counterfeited certification.

563 Packaging and Marking

563.1 General

Wettable packing materials and roots or butts of plants must be wrapped or

boxed in a waterproof material. The material must be heavy enough to retain

the moisture content needed for the roots of the plants without weakening

563.2 Hazardous, Restricted, and Perishable Mail

146 Publication 52

the strength of the box, and must be able to withstand Postal Service

handling without leakage or loss of the packing material or contents.

Waterproof material means one of the following:

a. Tar-centered paper.

b. Kraft paper waxed on one side.

c. Kraft paper with a waxed or tarred paper liner.

d. Plastic wrap.

563.2 Securing Tops of Bundles

The tops of all bundles must be wrapped with a covering of paper, straw, or

similar material to protect the plant from injury or drying out. If the plant has

thorns or pointed projections, the wrapper must be puncture proof.

564 Further Information

For further information about specific plants or diseases, or about

requirements for international shipments, consult the local county agriculture

agent or the following federal agency:

ANIMAL AND PLANT HEALTH INSPECTION SERVICE

US DEPARTMENT OF AGRICULTURE

4700 RIVER RD

RIVERDALE MD 20737-1228

57 Nonmailable Plant Pests, Injurious Animals, and

Illegally Taken Fish or Wildlife

571 General

Under the respective provisions in 39 U.S.C. 3015(a), (b), or (d), the following

items are nonmailable:

a. Any injurious animal, the importation or interstate shipment of which is

prohibited under 18 U.S.C. 42.

b. Any plant pest, the movement of which is prohibited under section 103

or 104 of the Federal Plant Pest Act (7 U.S.C. 150bb or 150cc).

c. Any fish or wildlife, the conveyance of which is prohibited under

section 3 of the Lacey Act Amendments of 1981 (16 U.S.C. 3372).

For more information, see Publication 14, Prohibitions and Restrictions on

Mailing Animals, Plants, and Related Matter.

572 Criminal Penalties

Criminal penalties are specified in 18 U.S.C. 1716d for mailing anything that

is nonmailable under 39 U.S.C. 3015(a), (b), or (d).

September 7, 2023 147

6 International Mail

61 General

This chapter contains regulations on the mailability of hazardous materials,

restricted matter, and perishable matter that may be sent as international

mail. Additional information on these subjects is contained in Chapters

3, 4,

and 5, and in Mailing Standards of the United States Postal Service,

International Mail Manual (IMM) 135–138.

611 Refusal by Air Carrier

Mailpieces refused by an air carrier that contain, or are suspected to contain,

hazardous, restricted, or perishable materials, must be handled in

accordance with

711.

62 Hazardous Materials: International Mail

621 General Requirements

621.1 Mailing Conditions

In international commerce, the term “dangerous goods” is commonly used to

describe hazardous materials.

Almost all hazardous materials are prohibited in international mail. The only

mailable hazardous materials are certain infectious substances, excepted

quantities of radioactive material that are allowed in domestic mail, certain

magnetized materials, and certain lithium and lithium-ion batteries. See

Exhibit 621.1 for a summary of the types of hazardous materials that are

eligible for mailing in international mail.

In certain situations, the few types of hazardous materials that are generally

permitted in international mail may be further restricted by the mailing

limitations imposed by an individual country. Because individual countries

have unique prohibitions and restrictions, it is always necessary to consult

the Individual Country Listings in the IMM to be certain that an otherwise

mailable hazardous material is acceptable for shipment to a specific country.

Exhibit 621.1

DOT Hazard Classes and Mailability for International Mail

Hazard

Class

Name of Hazard Class

(and Division when applicable)

International Mail

APO/FPO/DPO

Air

Transportation

Surface

Transportation

1 Explosives Prohibited Prohibited

2 Gases Prohibited Prohibited

3 Flammable and Combust

ible Liquids Prohibited Prohibited

4 Flammable Solids Prohibited Prohibited

5 Oxidizing Substances, Organic Peroxides Prohibited Prohibited

6 Toxic Substances and Infectious Substances

Division 6.1: Toxic Substances Prohibited Prohibited

Division 6.2: Infectious Substances Only via First-Class

ckage International

Service with Registered

Mail service per limits in

622.2 and IMM 135.1.

Prohibited

7 Radioactive Materials Only via First-Class

Package International

Service using Registered

Mail service per limits in

622.3 and IMM 135.5.

Prohibited

8 Corrosives (liquids and solids) Prohibited Prohibited

9 Miscellaneous Hazardous Materials Prohibited, except for

magnetized

materials per

622.4 and lithium or

lithium-ion batteries per

622.5

Prohibited, except for

magnetized materials

per 622.4 and lithium

batteries per

622.5

621.2 Hazardous, Restricted, and Perishable Mail

148 Publication 52

621.2 Hazard Classes

The nine classes of hazardous materials listed in 331 also apply to

dangerous goods shipped in international

commerce.

The non-Postal Service regulations that govern the air shipment of

azardous materials (dangerous goods) in international commerce are

specified in the Technical Instructions for the Safe Transport of Dangerous

Goods by Air of the International Civil Aviation Organization (ICAO). In

49 CFR, DOT recognizes ICAO requirements for the air transportation of

azardous materials. However, 49 CFR gives DOT the authority to regulate

only the domestic transportation of hazardous materials. Generally, most air

carriers follow the Dangerous Goods Regulations of the International Air

Transport Association (IATA), and those regulations are slightly more

restrictive than the ICAO rules.

621.3 Limited Quantity Air and Limited Quantity Ground

The Limited Quantity air and Limited Quantity surface category is unique

within domestic commerce and specific to the Postal Service networks.

These categories are not recognized in international commerce. Hazardous

materials under these classifications that are mailable in domestic mail are

typically prohibited in international mail.

International Mail 622.2

September 7, 2023 149

621.4 APO/FPO/DPO Mail

Hazardous, restricted, or perishable materials mailed to, from, and between

overseas military Post Offices are subject to the conditions of IMM 130, the

standards in this publication, conditions prescribed by the Department of

State international security policy, and conditions prescribed by the

Department of Defense (DOD), as listed in Overseas Military/Diplomatic Mail

in the Postal Bulletin. Also see DMM 703.2-4.

621.5 Extra Service Codes and Shipping Service Files

Mailers shipping dangerous goods internationally, including to APO/FPO/

DPO destinations utilizing PC Postage, eVS, USPS Ship, and ePostage

platforms, must include ESC 857 and incorporate the applicable content-

specific Extra Service Code (ESC) listed in Appendix G and Pub 199 and

transmit a Shipping Services File (SSF), using Version 1.7 or higher, or

Shipping Partner Event File (SPEF), using Version 5.0 or higher, to the Postal

Service before, or concurrent with, tendering dangerous-goods shipments.

622 Mailable Hazardous Materials

622.1 General

As shown in Exhibit 621.1, almost all hazardous materials are prohibited in

international mail. Under specific circumstances, only biological substances,

limited amounts of radioactive materials, and certain magnetized materials

are eligible to be sent in international mail.

622.2 Biological Substances, Division 6.2

Infectious and noninfectious biological substances are permitted in

international mail subject to the provisions that apply to domestic mail in

346.2. In addition, the following requirements apply:

a. Biological substances are prohibited from international mail by certain

countries. To determine if a prohibition exists for a specific country,

check the Individual Country Listings in the IMM.

b. Mailable infectious substances must only be sent via First-Class

Package International Service using Registered Mail service.

Nonregulated materials defined in

346.234 and exempt human or animal

specimens defined in 346.12d are mailable when properly packaged as

described in 346.32.

c. Biological substances can be sent to or received by only the following

types of institutions when permission has been granted:

(1) Laboratories of local, state, and federal government agencies.

(2) Laboratories of federally licensed manufacturers of biological

products derived from bacteria and viruses.

(3) Laboratories affiliated with or operated by hospitals, universities,

research facilities, and other teaching institutions.

(4) Private laboratories licensed, certified, recognized, or approved

by a public authority.

622.3 Hazardous, Restricted, and Perishable Mail

150 Publication 52

Permission to mail biological substances must be obtained prior to

mailing. Qualifying institutions wishing to mail biological substances

must submit a written letter of application on its organizational

letterhead to the following address:

DIRECTOR, PRODUCT CLASSIFICATION

US POSTAL SERVICE

475 L’ ENFANT PLZ SW RM 4446

WASHINGTON DC 20260-5015

The application must state the institution’s nature of work, the identity

and qualifications of the prospective recipient, and the number of

packages to be mailed.

d. Mailable infectious substances are limited to 50 ml for liquids or 50 g

for solids, per mailpiece, and must be packaged in accordance with

Packaging Instruction 6C in Appendix

C, and the additional

requirements in IMM 135.31 and 135.41.

e. Nonregulated materials and exempt human or animal specimens must

be packaged in accordance with Packaging Instructions 6G and 6H in

Appendix

C, and the additional requirements in IMM 135.32 and

135.42.

f. A shipper’s declaration for dangerous goods is required. See 326 and

725.3.

622.3 Radioactive Materials, Class 7

Class 7 radioactive materials are permitted in international mail subject to the

limits in

347 and the following conditions:

a. Radioactive materials may be sent only to those countries that have

expressed a willingness to accept them. For specific details, consult

the Individual Country Listings in the IMM.

b. Each radioactive materials shipment must be sent only by First-Class

Package International Service with Registered Mail service.

c. Mailable radioactive materials may not have an activity content that

exceeds one-tenth of the limits in Exhibit 347.22.

d. Each shipment must comply with both the International Atomic Energy

Agency Regulations and the specifications contained in

347 and this

section.

e. Mailable radioactive materials must be packaged in accordance with

Packaging Instruction 7A in Appendix

C and the requirements

specified in IMM 135.5.

f. The sender and recipient of each radioactive materials shipment must

receive prior authorization from the appropriate regulatory authorities

within their countries.

g. A white package label bearing the French words “Matieres

Radioactives” (Radioactive Materials) must be securely affixed, taped,

or gummed to the address side of each mailpiece containing

radioactive materials. The sender is responsible for supplying and

affixing this label to the mailpiece.

International Mail 622.51

September 7, 2023 151

h. The address side of each mailpiece must bear the following

endorsements in bold letters: “Return to Sender in Case of

Nondelivery” and “Radioactive Materials, Quantities Permitted for

Movement by Post.”

i. A shipper’s declaration for dangerous goods is required. See 326 and

725.3.

622.4 Magnetized Materials

Magnetized materials, as defined in 349.24, are prohibited in international

mail except for those that cannot cause a compass deviation at a distance of

7 feet or more. Mailable magnetized materials must be prepared for mailing

following Packaging Instruction 9B in Appendix

622.5 Lithium and Lithium-ion Cells and Batteries — General

Only lithium batteries under 622.51 and 622.52 that are properly installed in

the equipment they operate may be sent internationally or to, from, or

between APO, FPO, or DPO locations (subject to the conditions prescribed

by the U.S. Department of Defense listed in Overseas Military/Diplomatic

Mail in the Postal Bulletin). Used, damaged, defective, or recalled lithium

batteries and used, damaged, or defective electronic devices (excluding

devices that are new in original packaging, and manufacturer-certified new

or refurbished devices) containing or packaged with lithium batteries are

prohibited and may not be mailed internationally or to, from, or between

APO, FPO, or DPO locations under any circumstances. See

349.21.

The following restrictions also apply:

a. The batteries must be installed in the equipment being shipped.

b. The equipment must be cushioned to prevent movement or damage

and must be contained in rigid outer packaging, sealed and strong

enough to prevent crushing of the package or exposure of the contents

during normal handling in the mail.

c. A lithium battery consignment, as defined in 349.12b, is limited to a

maximum of two mailpieces for all international and APO/FPO/DPO

mailings.

622.51 Lithium Metal (Non-Rechargeable) Cells and Batteries

Small consumer-type lithium metal cells or batteries (lithium metal or lithium

alloy) like those used to power cameras and flashlights are mailable in a

single shipment with the following restrictions:

a. Each shipment may contain a maximum of four lithium cells or two

lithium batteries.

b. The lithium content must not exceed 1 gram (g) per cell.

c. The total aggregate lithium content must not exceed 2 g per battery.

d. The batteries installed in the equipment must be protected from

damage and short circuit.

622.52 Hazardous, Restricted, and Perishable Mail

152 Publication 52

e. The equipment must be equipped with an effective means of

preventing it from being inadvertently turned on or activated.

f. Mailpieces must not bear markings or labels identifying the contents as

lithium batteries.

622.52 Lithium-ion (Rechargeable) Cells and Batteries

Small consumer-type lithium-ion cells and batteries like those used to power

cell phones and laptop computers are mailable in a single shipment with the

following restrictions:

a. Each shipment may contain a maximum of four lithium-ion cells or two

lithium-ion batteries.

b. The watt-hour rating must not exceed 20 Wh per cell.

c. The watt-hour rating must not exceed 100 Wh per battery.

d. Each battery must bear the “Watt-hour” or “Wh” marking on the battery

to determine if it is within the limits defined in items b and c.

e. The batteries installed in the equipment must be protected from

damage and short circuit.

f. The equipment must be equipped with an effective means of

preventing it from being inadvertently turned on or activated.

g. Mailpieces must not bear markings or labels identifying the contents as

lithium batteries.

622.53 Very Small Lithium Metal and Lithium-ion Cells and Batteries

Each shipment containing very small lithium batteries, when installed in the equipment

they operate (including circuit boards), may contain a maximum of four lithium cells or

two lithium batteries. Very small cells/batteries are mailable internationally with the fol-

lowing conditions:

a. Each lithium metal cell and battery must contain no more than 0.3 gram

of lithium content.

b. Each lithium-ion cell/battery must have a watt-hour rating of not more

than 2.7 Wh.

c. Mailpieces must not bear markings or labels identifying the contents as

lithium batteries.

International Mail 623

September 7, 2023 153

Exhibit 622.5

International Lithium Battery Mailability

International APO/FPO/DPO

1, 2

Mailpiece Battery Limit

Lithium Metal or Lithium Alloy Batteries

4, 5

Small, non-rechargeable, consumer-type batteries

Contained in (properly i

nstalled in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the

uipment

Prohibited

Without the equipment they operate (individual

bat

teries in originally sealed packaging)

Prohibited

Lithium-ion or Lithium Polymer Batteries

6, 7

Small, rechargeable, consumer-type batteries

Contained in (properly i

nstalled in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the

uipment

Prohibited

Without the equipment they operate (individual

batteries in originally sealed packaging)

Prohibited

Very Small Lithium Metal or Lithium-ion Batteries

8, 9

Exception for very small consumer-type batteries in international transportation

Contained in (properly i

nstalled in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the

equipment

Prohibited

Without the equipment they operate (individual

bat

teries in originally sealed packaging)

Prohibited

1. Unless otherwise prohibited by the international destination country or specific APO/FPO/DPO ZIP Code location.

2. Used, damaged, defective, or recalled lithium batteries and use

d, damaged, or defective electronic devices containing or

packaged with lithium batteries are prohibited and may not be mailed internationally or to, from or between APO, FPO, or DPO

locations under any circumstances. This excludes devices that are new in original packaging, and manufacturer-certified new

or refurbished devices.

3. When a mailpiece limitation of 4 cells or 2 batteries is applicable, a mailpiece may co

ntain either 4 cells or 2 batteries, not both.

4. Each lithium metal or lithium alloy cell must not conta

in more than 1 g (gram) of lithium content.

5. Each lithium metal or lithium alloy

battery must not contain more than 2 g of aggregate lithium content.

6. Each lithium-ion or lithium polymer cell must not exceed more than 20 W

h (watt-hour rating).

7. Each lithium-ion or lithium polymer b

attery must not exceed 100 Wh.

8. Each lithium metal or lithium alloy cell or batter

y must not exceed 0.3 g of lithium content.

9. Each lithium-ion or lithium polymer cell or battery must not exceed a watt-hour rating of 2.7 W

Note: Shipments containing lithium batteries are not permitted in Global Express Guaranteed mailpieces.

623 Nonmailable Hazardous Materials

The following types of hazardous materials, as defined in Chapter 3, and

IMM 135–136, are prohibited in international

mail:

a. Class 1, explosives (including explosive devices) (

341).

b. Class 2, gases (

342).

c. Class 3, flammable and combustible liquids (

343).

d. Class 4, flammable solids including matches (

344).

e. Class 5, oxidizing substances and organic peroxides (

345).

f. Class 6, Division 6.1, toxic subs

tances (including irritants) (346).

63 Hazardous, Restricted, and Perishable Mail

154 Publication 52

g. Class 6, Division 6.2, infectious substances (346), except as permitted

in 622.2.

h. Class 7, radioactive materials (347), except as permitted in 622.3.

i. Class 8, corrosives (348).

j. Class 9, miscellaneous hazardous materials (349), except as permitted

in 622.4 and 622.5.

k. Dry ice (carbon dioxide solid) (349.23).

l. Magnetized materials capable of causing a compass deviation at a

distance of 7 feet or more (

349.24).

m. All damaged, defective, or recalled lithium batteries (see 349.21).

n. All used, damaged, or defective electronic devices containing or

packaged with lithium batteries (see

349.21). This excludes devices

that are new in original packaging, and manufacturer-certified new or

refurbished devices.

63 Restricted Matter: International Mail

631 APO/FPO/DPO Mail

Hazardous, restricted, or perishable materials mailed to, from, and between

overseas military Post Offices are subject to the conditions of IMM 130, the

standards in this publication, conditions prescribed by the Department of

State international security policy, and conditions prescribed by the

Department of Defense (DOD), as listed in Overseas Military/Diplomatic Mail

in the Postal Bulletin. Also see DMM 703.2-4.

632 Firearms

The requirements and prohibitions that apply to the mailing of firearms in

domestic mail, as stated in Chapter

4, also apply to international mail subject

to any restrictions in the Individual Country Listings in the IMM.

a. Nonautomatic and semiautomatic rifles, carbines, revolvers, and

pistols (regardless of caliber), except those of .50 caliber or less

manufactured before 1898.

b. Shotguns with barrels less than 18 inches long.

c. All machine guns, submachine guns, machine pistols, and fully

automatic rifles.

To obtain an export license, mailers should contact the following federal agency:

U.S DEPARTMENT OF STATE

PM/DTC STE 1200 SA-1

2401 E ST NW

WASHINGTON DC 20037-2915

Telephone: 202-663-2980

In addition, see IMM 540 for U.S. Department of State licensing requirements

applicable to the international mailing of arms or implements of war,

component parts, and related technical data.

International Mail 633

September 7, 2023 155

632.1 Export to APOs/FPOs/DPOs

Export of firearms to certain specified overseas military or diplomatic Post

Offices (APOs/ FPOs/DPOs) is prohibited. To determine if the mailing of

firearms to a specific APO, FPO, or DPO is prohibited, refer to the table titled

“Overseas Military/Diplomatic Mail,” which is published periodically in the

Postal Bulletin. Footnote F of this table lists the restrictions for mailing

firearms. If the destination military or diplomatic Post Office permits the

shipment of firearms (meaning no Footnote F restriction is assigned to the

specific APO, FPO, or DPO ZIP Code), the mailer must present an export

license obtained from the regional Bureau of Alcohol, Tobacco, Firearms and

Explosives (ATF) office.

632.2 Import

Under the following conditions, members of the armed forces may mail rifles

or shotguns without an import permit:

a. Incident to a permanent change of duty or release from active duty, any

member of the armed forces who has been stationed on active duty

outside the United States for the preceding 60 days may, without an

import permit, present up to three rifles or shotguns that are mailable to

the appropriate armed forces transportation officer to be forwarded to

the member’s residence as unaccompanied baggage officially shipped

through the mail. Firearms imported in this manner must be intended

for the member’s personal use.

b. Any member of the armed forces who wishes to import more than three

mailable firearms must prepare ATF Form 6, Application and Permit for

Importation of Firearms, Ammunition, and Implements of War, and

must comply with the Defense Transportation Regulation 4500.9-r and

other appropriate military directives.

c. The three-firearm limitation does not apply to mailable firearms for

which the member of the armed forces has proof of prior ownership in

the United States. A member may personally mail these other firearms

back into the United States, or to any of its possessions, if the member

can establish to the satisfaction of the U.S. Customs Service that he or

she previously took the firearms out of the United States or any of its

possessions.

d. Any member of the armed forces importing firearms under a, b, or c of

this section must prepare ATF Form 6A, Release and Receipt of

Imported Firearms, Ammunition, and Implements of War, under

27 CFR 178.114(b). In addition, the member’s authorized agent must

furnish this form and associated certification to the customs officer

releasing the firearms.

633 Inert Replica and Explosive Devices

The following types of replica or inert explosive devices are prohibited in

international mail:

a. Military ordnance, ammunition, and shells.

b. Grenades.

634 Hazardous, Restricted, and Perishable Mail

156 Publication 52

c. Similar devices that were originally designed for military or combative

use (including training).

634 Knives and Sharp Instruments

Knives and sharp instruments permitted to be mailed in domestic mail may

be mailed in international mail as permitted in the conditions specified for the

Individual Country Listings in the IMM.

635 Drugs

Drugs that are admissible in domestic mail (see Chapter 4) are also acceptable

in international and APO/FPO/DPO mail, provided there is no specific

exclusion by the destination country or military or diplomatic Post Office.

636 Controlled Substances

Controlled substances are not permitted in international mail. Controlled

substances addressed to APO/FPO/DPO destinations are subject to the

prohibitions in DMM 703.2.3 or 703.3.2, in addition to all requirements that

apply to domestic mail, as contained in Chapter

637 Other Restricted Matter

Materials that are nonmailable domestically are also prohibited in

international mail. The restricted materials include, but are not limited to,

intoxicating liquor; matter emitting obnoxious odor, motor vehicle master

keys, odd-shaped items sent in letter-size envelopes, abortive and

contraceptive devices, and certain building construction material. See IMM

135 and 136 for other general restrictions and prohibitions, and the Individual

Country Listings in the IMM for specific country restrictions and prohibitions.

64 Perishable Matter: International Mail

641 APO/FPO/DPO Mail

Hazardous, restricted, or perishable materials mailed to, from, and between

overseas military or diplomatic Post Offices are subject to the conditions of

IMM 130, the standards in this publication, conditions prescribed by the

Department of State international security policy, and conditions prescribed

by the Department of Defense (DOD), as listed in Overseas Military/

Diplomatic Mail in the Postal Bulletin. Also see DMM 703.2-4.

642 Animals

Most live or dead animals are nonmailable in international mail. Animals

mailed to the Republic of Palau, the Republic of the Marshall Islands, and the

Federated States of Micronesia require a permit issued by the government of

the destination country.

International Mail 643.21

September 7, 2023 157

When permitted by the destination country, only the following types of

animals are mailable:

a. Live bees, leeches, silkworms, and flies of the family Drosophilidae.

b. Thoroughly dried dead insects or reptiles.

c. Parasites and predators of injurious insects, provided all of the

following conditions are met:

(1) The parasites and predators of injurious insects are permitted in

domestic mail.

(2) They are useful in controlling harmful insects.

(3) They are exchanged by officially recognized scientific or health

agencies.

(4) They are sent by First-Class Mail International service, First-

Class Package International Service, or Priority Mail International

Flat Rate Envelopes or Small Flat Rate Priced Boxes.

(5) They are securely packaged in containers conforming to the

requirements for domestic mail.

643 Eggs

643.1 Fresh Eggs

Eggs may be mailed in international mail via Priority Mail International service

only as follows:

a. For shipments to all countries except Canada, eggs must be packed in

the following manner:

(1) Each egg must be packed in sufficient cushioning material.

(2) Eggs must be shipped in a metal egg container.

(3) The metal egg container must be enclosed in an outer container

of wood with sufficient cushioning material packed between the

inner and outer containers.

b. For shipments to Canada, eggs must be packed in the following manner:

(1) Each egg must be wrapped in protective material and placed on end.

(2) Eggs must be either packed in the manner prescribed for other

countries in

643.1a or packed in a wooden, papier-mâché, or other

box of rigid material having a well-fitting, tightly adjusted lid.

(3) Vacant space in the box must be filled with packing material to

prevent eggs from striking together or against the sides, top, or

bottom of the box.

643.2 Dried Whole Eggs

643.21 Commodity Credit Corporation Endorsement

Dried whole eggs purchased under the USDA’s Commodity Credit

Corporation program must carry an endorsement by the exporter or

authorized representative waiving any right to withdraw the parcel from the

mail or to have it returned. The endorsement must be written or stamped on

the address side of each mailpiece. These mailings may be made by Priority

Mail International service only.

643.22 Hazardous, Restricted, and Perishable Mail

158 Publication 52

643.22 Certificate

A certificate using the format shown in IMM Exhibit 553.121 (and repeated

here as

Exhibit 643.22) must be prepared and completed by the sender, and

presented at the time of mailing. The follow

ing conditions also apply:

a. A single certificate may cover any number

of mailpieces presented by

the same sender and in the same mailing, even if the mailpieces are

addressed to different countries.

b. A charge (see IMM 552) is made for each certificate or each parcel (if a

ingle certificate covers more than one parcel).

c. Postage to cover the certificate charge must be affixed to the

certificate and canceled

with the postmark of the office of mailing.

d. After being postmarked, the certificate must be signed by the

postma

ster (or designee) and returned to the sender.

Exhibit 643.22

Certificate of Mailing Dried Whole Eggs

CERTIFICATE OF MAILING DRIED WHOLE EGGS

I hereby certify that there has (have) been posted at this Post Office facility

today by (Sender), parcels containing a total of (Number) pounds of dried whole

eggs on which the sender has waived the right to withdraw same from the mail

or have same returned.

Parcels addressed to

(Name and addresses of addressees)

(Office stamp)

(Date)

(Postmaster)

644 Plants

Plants, seeds, and plant materials, including fruits and vegetables, are

subject to the provisions for domestic mail in section 56, Publication 14,

Prohibitions and Restrictions on Mailing Animals, Plants, and Related Matter,

and the quarantine regulations of the country of destination. Customers can

obtain information from the U.S. Department of Agriculture (USDA) Animal

and Plant Health Inspection Service (APHIS) Plant Protection and Quarantine

(PPQ) Programs at:

USDA APHIS PPQ

4700 RIVER RD

RIVERDALE MD 20737–1228

International Mail 645

September 7, 2023 159

645 Fresh Foods and Other Perishables

Fresh meats, fruits, vegetables, and other items that are capable of easily

decomposing or cannot reasonably be expected to reach their destination

without spoiling are nonmailable in international mail. Consult the Individual

Country Listing in the IMM for specific restrictions or prohibitions.

645 Hazardous, Restricted, and Perishable Mail

160 Publication 52

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September 7, 2023 161

7 Air Transportation Requirements

71 General

This chapter contains standards on the mailability of hazardous materials,

restricted matter, and perishable matter in domestic mail via air

transportation. (For international and APO/FPO/DPO mail, see Chapter

6.)

Full compliance with regulations governing shipping harmful matter by air

transportation is essential because these materials can endanger Postal

Service employees, airline passengers and personnel, aircraft equipment,

and Postal Service equipment and facilities.

For the purposes of this chapter, air transportation requirements apply to all

mailable hazardous materials, restricted matter, and perishable matter sent

via Priority Mail or First-Class Package International Service.

711 Refusal by Air Carrier

711.1 Air Carrier Policy or Pilot’s Decision

Although a mailpiece containing a mailable hazardous, perishable, or

restricted material may be properly prepared for air transportation under

Postal Service mailing requirements, an individual pilot may refuse it.

Nonmailable or improperly prepared mailpieces can also be rejected by an

air carrier when tendered for shipment. Refusals can result from the following

situations:

a. The air carrier is not authorized to carry hazardous materials under the

provisions of the Federal Aviation Administration (FAA) Operator’s

Certificate.

b. The air carrier’s corporate policy prohibits carrying hazardous or

restricted materials.

c. The pilot of an individual flight rejects any mailpieces perceived as

questionable or unsafe. Pilots have the right to refuse the boarding and

transport of questionable articles that could interfere or prevent the

safe operation of the aircraft under Federal Air Regulations (FAR).

d. The mailpiece contains a nonmailable hazardous or restricted material

that was mistakenly accepted or deposited in the mailstream.

e. The mailpiece is not properly packaged, marked, or labeled for air

transportation.

f. The mailpiece does not carry a properly completed shipper’s

declaration for dangerous goods.

711.2 Hazardous, Restricted, and Perishable Mail

162 Publication 52

g. The mailpiece is unidentified as to its contents and appears to contain

a hazardous or restricted material.

h. The air carrier refuses a mailable shipment of live animals or other

mailable articles of perishable matter because of its company policy on

safety or current extreme temperature conditions.

711.2 Handling of Mailpieces Refused by an Air Carrier

All mailpieces containing hazardous, restricted, or perishable materials that

are refused by an air carrier must be handled as follows:

a. If the mailpiece is damaged or leaking, contact the local facility’s safety

officer or designee for assistance. The procedures in the facility’s Spill/

Leak SOP and Handbook EL–812 must be followed.

b. An online Mailpiece Incident Report (MIR) is required to be completed

and filed in accordance with the instructions in the Safety Toolkit,

based on the incident type. Types of incidents may include spills,

leaks, or hazardous, restricted, or perishable material that has been

rejected by an air carrier.

c. If the mailpiece contains a nonmailable or improperly packaged

hazardous or restricted material, a nonmailable or improperly

packaged animal or other perishable matter, immediately follow the

reporting procedures in POM 139.117–118 and the Aviation Mail

Security Hazardous Materials Program Instructions, as applicable.

Additionally, to prevent future shipments from being incorrectly

accepted for mailing, notify the mailer and the mailing Post Office of

the problem.

d. If the mailpiece contains a mailable hazardous or restricted material

that is properly packaged, labeled, and marked, attempt to contact the

mailer. If the mailer can be reached, advise the mailer that the item has

been refused by the air carrier and offer to divert to surface

transportation or return to sender. If the mailer agrees to divert to

surface, apply Label 127, Surface Transportation Only, and

immediately dispatch the mailpiece to the destination via the most

expeditious means of surface transportation.

e. If the mailer cannot be contacted, or if the mailer does not wish to have

the mailpiece rerouted via surface transportation, or if the mailpiece

cannot be rerouted via surface transportation to the delivery address,

do the following:

(1) Affix Label 180, Rejected by Air Carrier, or endorse the address

side of the mailpiece “Refused for Air Transportation by Air

Carrier” and note the name of the airline, flight number, and

reason for refusal.

(2) Correct the markings on the mailpiece to read “Surface Mail

Only,” and return the mailpiece to the sender via surface

transportation (if permitted).

(3) Apply Label 127, Surface Transportation Only, and immediately

dispatch the mailpiece to the destination via the most

expeditious means of surface transportation.

Air Transportation Requirements 711.2

September 7, 2023 163

(4) Provide the mailer with instructions on how to obtain a refund of

the postage charges because service was not provided, and the

item was determined to be mailable.

(5) Complete PS Form 2759, Report of Irregular Handling of Mail, for

internal Postal Service information only, and distribute copies to

the appropriate Postal Service offices. Do not send a copy to the

mailer. Include the name and address of the mailer, the type and

amount of hazardous material, and the reason for the air carrier’s

refusal.

f. If the mailpiece contains mailable animals that cannot be delivered to

the addressee or returned to the sender via surface transportation

within 72 hours (for live day-old poultry), or within the delivery period

marked on the mailpiece (for other animals), immediately dispose of it.

For safety reasons, dispose of mailpieces not marked with a delivery

period when it reasonably appears the articles could not be delivered

or returned in a viable condition. Also dispose of, or donate to a

charitable institution, any perishable matter that cannot be returned in

a viable condition. See POM 691.52 for disposal information.

g. If the mailpiece contains a mailable animal or other article of perishable

matter that appears to be viable and can be delivered within the

specified delivery period, attempt to contact the mailer via information

from the return address. If the mailer can be reached, advise the mailer

of the available option for rerouting the mailpiece via the most

expeditious means of surface transportation (if available). If the mailer

agrees to divert to surface, apply Label 127, Surface Transportation

Only, and immediately dispatch the mailpiece to the destination via the

most expeditious means of surface transportation.

h. If the mailer of a parcel containing a mailable animal or other article of

perishable matter (that appears to be in a viable condition) cannot be

contacted, and the mailpiece can be returned to the sender within the

specified delivery period, do the following:

(1) Affix Label 180, Rejected by Air Carrier, or endorse the address

side of the mailpiece “Refused for Air Transportation by Air

Carrier” and note the name of the airline, flight number, and

reason for refusal.

(2) Apply Label 127, Surface Transportation Only, and immediately

return the mailpiece to the sender via the most expeditious

means of surface transportation.

(3) Provide the mailer with instructions on how to obtain a refund of

the postage charges because service was not provided, and the

item was determined to be mailable.

72 Hazardous, Restricted, and Perishable Mail

164 Publication 52

72 Hazardous Materials: Air Transportation

721 General Requirements

For domestic mail sent via air transportation, a mailpiece containing a

hazardous material must:

a. Consist of a material that is permitted to be transported by air.

b. Be prepared and packaged under all applicable conditions for

transport by air.

c. Be sent by Priority Mail Express, Priority Mail, or First-Class Package

International Service.

Hazardous materials are not acceptable for air transportation if they are not

prepared in compliance with the specific applicable requirements. These

requirements consider the degree of hazard, quantity of material, method of

packaging, required shipping papers, and adequacy of labels and/or

markings required for carriage aboard an aircraft.

Chapter 3 and the Packaging Instructions in Appendix C, provide full details

of the conditions under which mailable hazardous materials may be sent in

domestic mail via air transportation.

722 Additional Requirements

722.1 APO/FPO/DPO Mail

Hazardous, restricted, or perishable materials mailed to, from, and between

overseas military or diplomatic Post Offices are subject to the conditions of

IMM 130, the standards in this publication, conditions prescribed by the

Department of State international security policy, and conditions prescribed

by the Department of Defense (DOD), as listed in Overseas Military/

Diplomatic Mail in the Postal Bulletin. Also see Chapter

6 and DMM 703.2 for

information on air transportation and other restrictions affecting APO/FPO/

DPO, SAM, and PAL service.

722.2 ZIP Codes Served Only by Air Transportation

Hazardous materials that are prohibited from mailing via air transportation

cannot be mailed to any ZIP Code that is serviced only by air transportation

(e.g., certain ZIP Codes in Alaska).

722.3 Air Transportation Prohibitions

The following types of hazardous materials are prohibited from transport via

aircraft under any circumstances:

a. Explosives.

b. Anything susceptible to damage or that can become harmful because

of changes in temperature or atmospheric pressures, unless protected

against the effects of such changes.

c. Magnetic material that has a field strength sufficient to cause a

compass deviation at a distance of 7 feet or more from any point on the

outer packaging.

Air Transportation Requirements 725.2

September 7, 2023 165

d. Flammable materials (gases, liquids, and solids).

e. Radioactive materials.

f. Hazardous materials excluded from air shipment by the regulations of

49 CFR 100-185, or by the applicable country or air carrier operator

variations.

723 Hazardous Materials Warning Labels

See 325 for information on hazardous materials warning labels. Parcels

displaying any of the DOT warning labels shown in Exhibit 325.2 are

prohibited because items required to bear those warning labels contain

hazardous materials or quantities of hazardous materials that possess too

great a risk to be safely handled in the mail. Parcels displaying any of the

labels shown in

Exhibit 325.3a are permitted to be mailed within specific

limits set by the Postal Service and as defined in Chapter 3.

724 Consumer Commodity and Mailable Limited

Quantity Materials

Hazardous materials permitted to be sent in domestic mail via air

transportation must qualify as consumer commodity materials or air-eligible

mailable limited quantity materials, except for the few materials specified in

322 and Exhibit 331. See 333 and 334 for more information on air-eligible

hazardous materials.

To be acceptable for air transportation, a consumer commodity material or

mailable limited quantity materials must be eligible for shipment via air and

must be properly packaged and marked. The mailpiece must also bear a

shipper’s declaration for dangerous goods as required in

326 and 725.3.

725 Mailer Responsibility

725.1 General

Full responsibility rests with the mailer to comply with all Postal Service and

non-Postal Service laws and regulations regarding the mailing of hazardous

materials. Anyone who mails, or causes to be mailed, a nonmailable or

improperly packaged hazardous material can be subject to legal penalties,

including, but not limited to, those specified in 18 U.S.C.

725.2 Warning Labels and Marking Requirements

Except as noted, hazardous materials acceptable for air transportation

generally fall within the consumer commodity or mailable limited quantity

categories. Mailpieces containing these materials and intended for air

transportation have specific marking requirements, including the use of

certain DOT hazard class warning labels. Some air-eligible mailable

hazardous materials also have marking and packaging requirements that are

unique to mailpieces entered under these exceptions (e.g. SP 9275, certain

725.3 Hazardous, Restricted, and Perishable Mail

166 Publication 52

mailable infectious substances and medical waste, and dry ice). Mailable

hazardous material must bear DOT handling labels (such as orientation

arrows, magnetized materials, etc.) when applicable. The following also apply:

a. Mailpieces containing air-eligible materials in hazard Classes 2, 3, and

6.1, or portions of 9 must bear DOT square-on-point markings and an

approved DOT Class 9 hazardous material warning label (see

Exhibit 325.3b). The top and bottom portions of the square-on-point

and the border forming the square-on-point must be black, and the

center must be white or of a suitable contrasting background. The

symbol “Y” must be black, located in the center of the square-on-

point, and clearly visible. Mailpieces must also be marked with the

proper shipping name “Consumer Commodity” and identification

number “ID8000.” A shipper’s declaration for dangerous goods,

prepared in triplicate, must be affixed to the outside of the mailpiece.

b. Mailpieces containing air-eligible materials in hazard Classes 5.1, 5.2,

or 8 must bear a DOT square-on-point marking and the appropriate

approved DOT Class 5.1, 5.2, or 8 hazardous material warning label.

The top and bottom portions of the square-on-point and the border

forming the square-on-point must be black, and the center must be

white or of a suitable contrasting background. The symbol “Y” must be

black, located in the center of the square-on-point, and clearly visible.

Mailpieces must also be marked with the appropriate identification

number and the proper shipping name. A properly completed shipper’s

declaration for dangerous goods must be affixed to the outside of the

mailpiece.

c. Markings must be durable, legible, and readily visible, and must be

applied on at least one side or one end of the outer packaging. The

border forming the square-on-point must be at least 2 mm in width,

and the minimum dimension of each side must be 100 mm, unless the

package size requires a reduced size marking of no less than 50 mm

on each side.

725.3 Shipping Papers

Most mailable hazardous materials (including consumer commodity

materials or mailable limited quantity materials) must be accompanied by a

Shipper’s Declaration for Dangerous Goods (shipping paper, see

326). To

determine which mailable hazardous materials require a shipping paper

when sent via air transportation, refer to the appropriate sections in

Chapter

3, and the appropriate Packaging Instruction in Appendix C.

The shipping paper must be properly completed and signed in triplicate by

the mailer. It must bear a red candy-striped border and the exact format and

same basic wording as shown in

Exhibit 326. The shipper’s declaration must

be properly prepared, as required by 49 CFR 172.200 through 172.205,

which, in part, requires the following information:

a. Proper shipping name of material.

b. Hazard class.

c. UN or NA identification number, as applicable.

d. The quantity and type of packaging.

Air Transportation Requirements 727

September 7, 2023 167

e. The packaging instruction used.

f. The full name, address, and telephone number of the shipper or

consignee.

g. The signed shipper’s certification statement.

Neither the Postal Service nor DOT stocks or furnishes shipper’s declaration

forms. Mailers may obtain them from commercial printers, Internet-based

retailers, safety supply stores, or stationery stores.

725.4 Addressing

The full names and addresses of both the sender and the addressee must

appear legibly on the address side of the mailpiece, in accordance with

DMM

602.

726 Postal Service Handling

726.1 Acceptance Personnel

In addition to the basic guidelines in 251, acceptance personnel must follow

the Aviation Mail Security Hazardous Materials Program Instructions for the

acceptance of hazardous materials. Ensure the following:

a. Each mailpiece presented contains a mailable hazardous material that

is properly packaged and labeled.

b. If required, the mailpiece bears the required shipper’s declaration for

dangerous goods (see

326 and 725.3).

c. The mailpiece is eligible for air transportation and mailed as Priority

Mail Express, Priority Mail, or First-Class Package International

Service, as permitted.

d. These mailpieces must never be marked “Surface Mail” or “Surface

Mail Only.”

Note: For safety reasons, mailers are not permitted to pay postage

at Priority Mail Express or Priority Mail prices for mailpieces

containing hazardous materials that are not eligible for air

transportation.

726.2 Dispatch Personnel

In addition to the basic guidelines in 252, Postal Service personnel involved

with mail dispatch via air transportation must follow the Aviation Mail

Security, Hazardous Materials Program Instructions and the POM. These

policy statements provide interim field instructions for handling mailpieces

containing hazardous materials within mail processing areas and the proper

tendering of such mail to the air carriers.

727 Refusal by Air Carrier

Mailpieces refused by an air carrier that contain hazardous material, or are

suspected to contain hazardous materials, must be handled in accordance

with

711.

727.1 Hazardous, Restricted, and Perishable Mail

168 Publication 52

727.1 Nonmailable or Improperly Prepared Mailpieces

Mailpieces containing nonmailable or improperly packaged hazardous

materials that were inadvertently accepted for mailing should be stopped

where identified and not presented to an air carrier. They should be handled

in accordance with the Aviation Mail Security Hazardous Materials Program

Instructions. Additionally, to prevent future shipments from being incorrectly

accepted for mailing, notify the mailer and the Post Office of mailing of the

problem.

728 Spills and Leaks

The standard procedures to be followed by Postal Service personnel for

dealing with spills and leaks are specified in Management Instruction

EL-810-2006-3, Response to Hazardous Materials Releases, and

Handbook

EL-812, Hazardous Materials and Spill Response.

73 Restricted Matter: Air Transportation

Restricted matter includes articles for which certain mailing restrictions have

been imposed for reasons other than risk of harm to persons or property

involved in moving the mail. Refer to Chapter

4 for mailing information on

restricted matter.

731 Refusal by Air Carrier

Certain restricted articles, as described in 49 CFR 100-185 and the operator

variations of the air carriers, may be accepted for air transportation if

properly packaged. These articles must be labeled and bear a shipper's

declaration in triplicate, as required by 49 CFR 172.204, or must be marked

according to the air carrier's operator variations. Refer to the technical

instruction of the International Civil Aviation Organization (ICAO) for air carrier

operator variations.

Mailpieces refused by an air carrier that contain restricted matter, or are

suspected to contain hazardous matter, must be handled in accordance

with

711.

74 Perishable Matter: Air Transportation

741 General Requirements

Perishable matter is any item that can readily deteriorate during normal mail

transport conditions and thereby lose value, create a health hazard, or cause

a nuisance or disturbance.

Air Transportation Requirements 743

September 7, 2023 169

742 Live Animals

742.1 Basic Conditions

Most mailable live animals, except honeybees, are permitted to be sent via

air transportation. However, the ability of the Postal Service to provide air

transportation is dependent on the following:

a. The animal must be mailable and eligible for transport via air.

b. All provisions of airline tariffs and air carriers are met.

c. Air carrier equipment is available to the Postal Service and allows the

safe delivery of shipments within specified and reasonable time limits.

Time allowance must also be provided for delays en route in air and

ground transportation.

Note: Local Postal Service personnel are not authorized to refuse

the deposit of mailable live animals that are properly packaged.

See

523.

742.2 Bees

Only queen honeybees are permitted to be sent in the domestic mail via air

transportation (see

526.2 and Exhibit 526.21).

742.3 Refusal by Air Carrier

Mailpieces refused by an air carrier that contain live animals or other

perishable matter, or are suspected to contain perishable matter, must be

handled in accordance with

711.

743 Perishable Matter with Dry Ice

A mailpiece containing mailable matter that is packed in dry ice (carbon

dioxide solid) to cool the perishable contents must meet all requirements in

349 that apply to sending dry ice in domestic mail via air transportation. For

air transportation, the amount of dry ice cannot exceed 5 pounds per

mailpiece. Dry ice is prohibited to be mailed to international or APO/FPO/

DPO addresses.

743 Hazardous, Restricted, and Perishable Mail

170 Publication 52

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September 7, 2023 171

Appendix A

Hazardous Materials Table: Postal Service

Mailability Guide

The mailing information in this table is based on the online DOT Hazardous

Materials Table in 49 CFR 172.101 (dated December 30, 2013). The

information is modified to identify the mailability of each hazardous material

based on Postal Service mailing regulations. This table identifies the

mailability of hazardous materials for domestic mail only. Almost no

hazardous materials are permitted in international mail. For information on

mailability in international mail, see Chapter

6 and Exhibit 621.1.

In the domestic mail, generally only those hazardous materials meeting all of

the following criteria are eligible for mailing:

a. Designated by DOT as being eligible to be transported under its

Limited Quantity Provision,

b. Packaged and distributed in a quantity and form intended or suitable

for retail sale, and

c. Designed for consumption by individuals for their personal care or

household uses (i.e. consumer commodity material) are eligible for

mailing and subject to postal quantity limitations.

The only exceptions to the above criteria are for the small number of

materials listed in

322.

The columns in the hazardous materials table lists the mailability according

to Postal Service regulations. If the entry is “Prohibited,” the material is

nonmailable. If the entry cites a reference to this publication, the material is

subject to those requirements and restrictions. If the entry is “Limited

Quantity,” the material is mailable only if it can qualify as a Limited Quantity

air material or Limited Quantity surface material in the Postal Service.

Limited Quantity air and Limited Quantity surface materials cannot exceed

the postal quantity limits specified in this publication. The mailer is

responsible for correctly determining if the hazardous material is eligible in

the Postal Service networks. If assistance is needed, the mailer may request

a ruling from the PCSC as provided in

215.2. If the hazardous material is

mailable in the domestic mail, refer to Column (e) and (f), as appropriate, to

determine the applicable postal packaging instruction in Appendix C.

The columns in the table contain the following information:

Column (a): Lists the proper shipping name of the hazardous material in

roman type. Text that appears in italic type is not part of the proper shipping

name of the hazardous material and is listed for descriptive or reference

purposes. Some listings direct the user to the preferred proper shipping

Appendix A Hazardous, Restricted, and Perishable Mail

172 Publication 52

name of a material listed elsewhere in the table. The text in this column

closely matches the information in Column 2 of the Hazardous Materials

Table in 49 CFR 172.101.

Column (b): Lists the assigned hazard class or division of the hazardous

material. The entry “Forbidden” means the material may not be transported

under any circumstances. The entry “n/a” means the material does not have

an assigned hazard class. If the field is blank, refer to the listing for the

preferred proper shipping name cited in Column (a). The text in this column

closely matches the information in Column 3 of the Hazardous Materials

Table in 49 CFR 172.101.

Column (c): Lists the identification (ID) number assigned to the hazardous

material. The number may be either a United Nations (UN) number or a North

American (NA) number. This field is blank if Column (a) directs the user to the

listing for the preferred proper shipping name of the material, or if the entry in

Column (b) is “Forbidden.” The text in this column closely matches the

information in Column 4 of the Hazardous Materials Table in 49 CFR 172.101.

Column (d): Lists the DOT Packing Group (PG) assignment for the

hazardous material. Not all hazard classes have DOT Packing Group

assignments. If this field contains “n/a,” the material is in a hazard class that

does not use Packing Group assignments. This field is blank if Column (a)

directs the user to the listing for the preferred proper shipping name of the

material, or if the entry in Column (b) is “Forbidden.” The text in this column

closely matches the information in Column 5 of the Hazardous Materials

Table in 49 CFR 172.101.

Column (e): Lists the USPS packaging instruction in Appendix C that must

be followed if the hazardous material is permitted in domestic mail via air

transportation. This field is blank if Column (a) directs the user to the listing

for the preferred proper shipping name of the material, or if the hazardous

material is prohibited from mailing as designated in Column (e). If the entry in

this column is “Prohibited,” the material is not permitted in domestic mail via

air transportation.

Column (f): Lists the USPS packaging instruction in Appendix C that must

be followed if the hazardous material is permitted in domestic mail via

surface transportation. This field is blank if Column (a) directs the user to the

listing for the preferred proper shipping name of the material, or if the

hazardous material is prohibited from mailing as designated in Column (e). If

the entry in this column is “Prohibited,” the material is not permitted in

domestic mail via surface transportation.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Accellerene, see p-

Nitrosodimethylaniline

Accumulators, electric, see Batteries,

wet etc.

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 173

Accumulators, pressurized,

pneumatic or hydraulic (containing

nonflammable gas), see Articles

pressurized, pneumatic or hydraulic

(containing nonflammable gas)

Acetal 3 UN1088 II Prohibited 3A

Acetaldehyde 3 UN1089 I Prohibited Prohibited

Acetaldehyde ammonia 9 UN1841 III Prohibited 9C

Acetaldehyde oxime 3 UN2332 III Prohibited 3A

Acetic acid, glacial or Acetic acid

solution, with more than 80

percent

acid, by mass

8 UN2789 II 8A 8A

Acetic acid solution, not less than

percent but not more than

80 percent acid, by mass

8 UN2790 II 8A 8A

Acetic acid solution, with more than

percent and less than 50 percent

acid, by mass

8 UN2790 III 8A 8A

Acetic anhydride 8 UN1715 II 8A 8A

Acetone 3 UN1090 II Prohibited 3A

Acetone cyanohydrin, stabilized 6.1 UN1541 I Prohibited Prohibited

Acetone oils 3 UN1091 II Prohibited 3A

Acetonitrile 3 UN1648 II Prohibited 3A

Acetyl acetone peroxide with more

than 9 percent by mass active

oxygen

Forbidden Prohibited Prohibited Prohibited Prohibited

Acetyl benzoyl peroxide, solid, or

with more than 40 percent in

solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Acetyl bromide 8 UN1716 II 8A 8A

Acetyl chloride 3 UN1717 II Prohibited Prohibited

Acetyl cyclohexanesulfonyl peroxide,

with more than 82 percent wetted

with less than 12 percent water

Forbidden Prohibited Prohibited Prohibited Prohibited

Acetyl iodide 8 UN1898 II 8A 8A

Acetyl methyl carbinol 3 UN2621 III Prohibited 3A

Acetyl peroxide, solid, or with more

than 25

percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Acetylene, dissolved 2.1 UN1001 n/a Prohibited Prohibited

Acetylene (liquified) Forbidden Prohibited Prohibited Prohibited Prohibited

Acetylene silver nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Acetylene, solvent free Forbidden Prohibited Prohibited Prohibited Prohibited

Acetylene tetrabromide, see

Tetrabromoethane

Acid butyl phosphate, see Butyl acid

phosphate

Acid, sludge, see Sludge, acid

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

174 Publication 52

Acridine 6.1 UN2713 III 6A 6A

Acrolein dimer, stabilized 3 UN2607 III Prohibited 3A

Acrolein, stabilized 6.1 UN1092 I Prohibited Prohibited

Acrylamide, solid 6.1 UN2074 III 6A 6A

Acrylamide, solution 6.1 UN3426 III 6A 6A

Acrylic acid, stabilized 8 UN2218 II 8A 8A

Acrylonitrile, stabilized 3 UN1093 I Prohibited Prohibited

Actuating cartridge, explosive, see

Cartridges, power device

Adhesives, containing a flammable

liquid

3 UN1133 I, II, III Prohibited 3A

Adiponitrile 6.1 UN2205 III 6A 6A

Aerosols, corrosive, Packing Group II

or III, (each not exceeding 1 L

capacity)

2.2 UN1950 n/a 2B 2B

Aerosols, flammable (each not

exceeding 1 L capacity)

2.1 UN1950 n/a Prohibited 2A

Aerosols, flammable, n.o.s. (engine

starting fluid) (each not exceeding 1

L capacity)

2.1 UN1950 n/a Prohibited 2A

Aerosols, nonflammable (each not

exceeding 1 L capacity)

2.2 UN1950 n/a 2B 2B

Aerosols, poison, each not exceeding

1 L capacity

2.2 UN1950 n/a 2B 2B

Air bag inflators, or Air bag modules,

or Seatbelt pretensioners

1.4G UN0503 II Prohibited Prohibited

Air bag inflators, or Air bag modules,

or Seatbelt pretensioners

9 UN3268 III Prohibited Prohibited

Air, compressed 2.2 UN1002 n/a 2B 2B

Air, refrigerated liquid (cryogenic

liquid)

2.2 UN1003 n/a Prohibited Prohibited

Air, refrigerated liquid (cryogenic

liquid), nonpressurized

2.2 UN1003 n/a Prohibited Prohibited

Aircraft engines (including turbines),

see Engines, internal combustion

Aircraft evacuation slides, see

Lifesaving appliances etc.

Aircraft hydraulic power unit fuel tank

(containing a mixture of anhydrous

hydrazine and monomethyl

hydrazine) (M86 fuel)

3 UN3165 I Prohibited Prohibited

Aircraft survival kits, see Lifesaving

appliances etc.

Alcoholates solution, n.o.s., in

alcohol

3 UN3274 II Prohibited Prohibited

Alcoholic beverages 3 UN3065 II, III Prohibited Prohibited

Alcohols, n.o.s. 3 UN1987 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 175

Alcohols, n.o.s. 3 UN1987 II, III Prohibited 3A

Alcohols, flammable, toxic, n.o.s. 3 UN1986 I, II, III Prohibited Prohibited

Aldehydes, n.o.s. 3 UN1989 I Prohibited Prohibited

Aldehydes, n.o.s. 3 UN1989 II, III Prohibited 3A

Aldehydes, flammable, toxic, n.o.s. 3 UN1988 I, II Prohibited Prohibited

Aldehydes, flammable, toxic, n.o.s. 3 UN1988 III Prohibited 3A

Aldol 6.1 UN2839 II Prohibited Prohibited

Aldrin, liquid 6.1 NA2762 II Prohibited Prohibited

Aldrin, solid 6.1 NA2761 II Prohibited Prohibited

Alkali metal alcoholates, selfheating,

corrosive, n.o.s.

4.2 UN3206 II, III Prohibited Prohibited

Alkali metal alloys, liquid, n.o.s. 4.3 UN1421 I Prohibited Prohibited

Alkali metal amalgam, liquid 4.3 UN1389 I Prohibited Prohibited

Alkali metal amalgam, solid 4.3 UN3401 I Prohibited Prohibited

Alkali metal amides 4.3 UN1390 II Prohibited 4A

Alkali metal dispersions, flammable

or Alkaline earth metal dispersions,

flammable

4.3 UN3482 I Prohibited Prohibited

Alkali metal dispersions, or Alkaline

earth metal dispersions

4.3 UN1391 I Prohibited Prohibited

Alkaline corrosive liquids, n.o.s., see

Caustic alkali liquids, n.o.s.

Alkaline earth metal alcoholates,

n.o.s.

4.2 UN3205 II, III Prohibited Prohibited

Alkaline earth metal alloys, n.o.s. 4.3 UN1393 II Prohibited 4A

Alkaline earth metal amalgams, liquid 4.3 UN1392 I Prohibited Prohibited

Alkaline earth metal amalgams, solid 4.3 UN3402 I Prohibited Prohibited

Alkaloids, liquid, n.o.s., or Alkaloid

salts, liquid, n.o.s.

6.1 UN3140 I, II Prohibited Prohibited

Alkaloids, liquid, n.o.s., or Alkaloid

salts, liquid, n.o.s.

6.1 UN3140 III 6A 6A

Alkaloids, solid, n.o.s. or Alkaloid

salts, solid, n.o.s. poisonous

6.1 UN1544 I, II Prohibited Prohibited

Alkaloids, solid, n.o.s. or Alkaloid

salts, solid, n.o.s. poisonous

6.1 UN1544 III 6A 6A

Alkyl sulfonic acids, liquid or Aryl

sulfonic acids, liquid with more than

percent free sulfuric acid

8 UN2584 II 8A 8A

Alkyl sulfonic acids, liquid or Aryl

sulfonic acids, liquid with not more

than 5

percent free sulfuric acid

8 UN2586 III 8A 8A

Alkyl sulfonic acids, solid or Aryl

sulfonic acids, solid with more than

percent free sulfuric acid

8 UN2583 II 8A 8A

Alkyl sulfonic acids, solid or Aryl

sulfonic acids, solid with not more

than 5

percent free sulfuric acid

8 UN2585 III 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

176 Publication 52

Alkylphenols, liquid, n.o.s. (including

C2C12 homologues)

8 UN3145 I Prohibited Prohibited

Alkylphenols, liquid, n.o.s. (including

C2-C12 homologues)

8 UN3145 II, III 8A 8A

Alkylphenols, solid, n.o.s. (including

C2-C12 homologues)

8 UN2430 I Prohibited Prohibited

Alkylphenols, solid, n.o.s. (including

C2-C12 homologues)

8 UN2430 II, III 8A 8A

Alkylsulfuric acids 8 UN2571 II 8A 8A

Allethrin, see Pesticides, liquid, toxic,

n.o.s.

Allyl acetate 3 UN2333 II Prohibited Prohibited

Allyl alcohol 6.1 UN1098 I Prohibited Prohibited

Allyl bromide 3 UN1099 I Prohibited Prohibited

Allyl chloride 3 UN1100 I Prohibited Prohibited

Allyl chlorocarbonate, see Allyl

chloroformate

Allyl chloroformate 6.1 UN1722 I Prohibited Prohibited

Allyl ethyl ether 3 UN2335 II Prohibited Prohibited

Allyl formate 3 UN2336 I Prohibited Prohibited

Allyl glycidyl ether 3 UN2219 III Prohibited 3A

Allyl iodide 3 UN1723 II Prohibited Prohibited

Allyl isothiocyanate, stabilized 6.1 UN1545 II Prohibited Prohibited

Allylamine 6.1 UN2334 I Prohibited Prohibited

Allyltrichlorosilane, stabilized 8 UN1724 II Prohibited Prohibited

Aluminum borohydride or Aluminum

borohydride in devices

4.2 UN2870 I Prohibited Prohibited

Aluminum bromide, anhydrous 8 UN1725 II 8A 8A

Aluminum bromide, solution 8 UN2580 III 8A 8A

Aluminum carbide 4.3 UN1394 II Prohibited 4A

Aluminum chloride, anhydrous 8 UN1726 II 8A 8A

Aluminum chloride, solution 8 UN2581 III 8A 8A

Aluminum dross, wet or hot Forbidden Prohibited Prohibited Prohibited Prohibited

Aluminum ferrosilicon powder 4.3 UN1395 II, III Prohibited 4A

Aluminum hydride 4.3 UN2463 I Prohibited Prohibited

Aluminum, molten 9 NA9260 III Prohibited Prohibited

Aluminum, nitrate 5.1 UN1438 III 5A 5A

Aluminum phosphate solution, see

Corrosive liquids, etc.

Aluminum phosphide 4.3 UN1397 I Prohibited Prohibited

Aluminum phosphide pesticides 6.1 UN3048 I Prohibited Prohibited

Aluminum powder, coated 4.1 UN1309 II, III Prohibited 4A

Aluminum powder, uncoated 4.3 UN1396 II, III Prohibited 4A

Aluminum resinate 4.1 UN2715 III Prohibited 4A

Aluminum silicon powder, uncoated 4.3 UN1398 III Prohibited 4A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 177

Aluminum smelting by-products

or Aluminum remelting by-products

4.3 UN3170 II, III Prohibited Prohibited

Amatols, see Explosives, blasting,

type B

Amine, flammable, corrosive, n.o.s.

or Polyamines, flammable,

corrosive, n.o.s.

3 UN2733 I, II Prohibited Prohibited

Amine, flammable, corrosive, n.o.s.

or Polyamines, flammable,

corrosive, n.o.s.

3 UN2733 III Prohibited 3A

Amine, liquid, corrosive,

flammable, n.o.s. or Polyamines,

liquid, corrosive, flammable, n.o.s.

8 UN2734 I, II Prohibited Prohibited

Amines, liquid, corrosive, n.o.s.

or Polyamines, liquid, corrosive,

n.o.s.

8 UN2735 I Prohibited Prohibited

Amines, liquid, corrosive, n.o.s.

or Polyamines, liquid, corrosive,

n.o.s.

8 UN2735 II, III 8A 8A

Amines, solid, corrosive, n.o.s.

or Polyamines, solid, corrosive,

n.o.s.

8 UN3259 I Prohibited Prohibited

Amines, solid, corrosive, n.o.s.

or Polyamines, solid, corrosive,

n.o.s.

8 UN3259 II, III 8A 8A

2-Amino-4-chlorophenol 6.1 UN2673 II Prohibited Prohibited

2-Amino-5-diethylaminopentane 6.1 UN2946 III 6A 6A

2-Amino-4,6-Dinitrophenol, wetted

with not less than 20

percent water

by mass

4.1 UN3317 I Prohibited Prohibited

2-(2-Aminoethoxy) ethanol 8 UN3055 III 8A 8A

N-Aminoethylpiperazine 8 UN2815 III 8A 8A

Aminophenols (o-; m-; p-) 6.1 UN2512 III 6A 6A

Aminopropyldiethanolamine, see

Amines, etc.

n-Aminopropylmorpholine, see

Amines, etc.

Aminopyridines (o-; m-; p-) 6.1 UN2671 II Prohibited Prohibited

Ammonia, anhydrous (international) 2.3 UN1005 n/a Prohibited Prohibited

Ammonia, anhydrous (domestic) 2.2 UN1005 n/a Prohibited Prohibited

Ammonia solution, relative density

between 0.880 and 0.957 at 15° C

in water, with more than 10 percent

but not more than 35

percent

ammonia

8 UN2672 III 8A 8A

Ammonia solution, relative density

less than 0.880 at 15° C in water,

with more than 35 percent but not

more than 50

percent ammonia

2.2 UN2073 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

178 Publication 52

Ammonia solution, relative density

less than 0.880 at 15° C in water,

with more than 50

percent ammonia

2.2 UN3318 n/a Prohibited Prohibited

Ammonia solution, relative density

less than 0.880 at 15° C in water,

with more than 50

percent ammonia

2.3 UN3318 n/a Prohibited Prohibited

Ammonium arsenate 6.1 UN1546 II Prohibited Prohibited

Ammonium azide Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium bifluoride, solid, see

Ammonium hydrogen difluoride,

solid

Ammonium bifluoride, solution, see

Ammonium hydrogen difluoride,

solution

Ammonium bromate Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium chlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium dichromate 5.1 UN1439 II 5A 5A

Ammonium dintro-o-cresolate, solid 6.1 UN1843 II Prohibited Prohibited

Ammonium dintro-o-cresolate,

solution

6.1 UN3424 II Prohibited Prohibited

Ammonium fluoride 6.1 UN2505 III 6A 6A

Ammonium fluorosilicate 6.1 UN2854 III 6A 6A

Ammonium fulminate Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium hydrogen sulfate 8 UN2506 II 8A 8A

Ammonium hydrogendifluoride, solid 8 UN1727 II 8A 8A

Ammonium hydrogendiflouride,

solution

8 UN2817 II Prohibited Prohibited

Ammonium hydrogendiflouride,

solution

8 UN2817 III 8A 8A

Ammonium hydrosulfide, solution,

see Ammonium sulfide solution

Ammonium hydroxide, see Ammonia

solutions, etc.

Ammonium metavanadate 6.1 UN2859 II Prohibited Prohibited

Ammonium nitrate fertilizers 5.1 NA2072 III 5A 5A

Ammonium nitrate based fertilizers 5.1 UN2067 III 5A 5A

Ammonium nitrate based fertilizers 9 UN2071 III 9C 9C

Ammonium nitrate-fuel oil mixture

containing only prilled ammonium

nitrate and fuel oil

1.5D NA0331 II Prohibited Prohibited

Ammonium nitrate, liquid (hot

concentrated solution)

5.1 UN2426 n/a Prohibited Prohibited

Ammonium nitrate mixed fertilizers 5.1 NA2069 III 5A 5A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 179

Ammonium nitrate, with more

than 0.2 percent combustible

substances, including any organic

substance calculated as carbon, to

the exclusion of any other added

substance

1.1D UN0222 II Prohibited Prohibited

Ammonium nitrate, with not more

than 0.2

percent of combustible

substances, including any organic

substance calculated as carbon, to

the exclusion of any other added

substance

5.1 UN1942 III 5A 5A

Ammonium nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium perchlorate 1.1D UN0402 II Prohibited Prohibited

Ammonium perchlorate 5.1 UN1442 II 5A 5A

Ammonium permanganate Forbidden Prohibited Prohibited Prohibited Prohibited

Ammonium persulfate 5.1 UN1444 III 5A 5A

Ammonium picrate, dry or wetted

with less than 10 percent water, by

mass

1.1D UN0004 II Prohibited Prohibited

Ammonium picrate, wetted with not

less than 10 percent water, by mass

4.1 UN1310 I Prohibited Prohibited

Ammonium polysulfide, solution 8 UN2818 II Prohibited Prohibited

Ammonium polysulfide, solution 8 UN2818 III 8A 8A

Ammonium polyvanadate 6.1 UN2861 II 6A 6A

Ammonium silicofluoride, see

Ammonium fluorosilicate

Ammonium sulfide solution 8 UN2683 II Prohibited Prohibited

Ammunition, blank, see Cartridges

for weapons, blank

Ammunition, illuminating with or

without burster, expelling charge, or

propelling charge

1.2G UN0171 II Prohibited Prohibited

Ammunition, illuminating with or

without burster, expelling charge, or

propelling charge

1.3G UN0254 II Prohibited Prohibited

Ammunition, illuminating with or

without burster, expelling charge, or

propelling charge

1.4G UN0297 II Prohibited Prohibited

Ammunition, incendiary liquid or gel,

with burster, expelling charge, or

propelling charge

1.3J UN0247 II Prohibited Prohibited

Ammunition, incendiary (water-

activated contrivances) with burster,

expelling charge, or propelling

charge, see Contrivances, water-

activated, etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

180 Publication 52

Ammunition, incendiary, white

phosphorus, with burster, expelling

charge, or propelling charge

1.2H UN0243 II Prohibited Prohibited

Ammunition, incendiary, white

phosphorus, with burster, expelling

charge, or propelling charge

1.3H UN0244 II Prohibited Prohibited

Ammunition, incendiary with or

without burster, expelling charge, or

propelling charge

1.2G UN0009 II Prohibited Prohibited

Ammunition, incendiary with or

without burster, expelling charge, or

propelling charge

1.3G UN0010 II Prohibited Prohibited

Ammunition, incendiary with or

without burster, expelling charge, or

propelling charge

1.4G UN0300 II Prohibited Prohibited

Ammunition, practice 1.4G UN0362 II Prohibited Prohibited

Ammunition, practice 1.3G UN0488 II Prohibited Prohibited

Ammunition, proof 1.4G UN0363 II Prohibited Prohibited

Ammunition, rocket, see Warheads,

rocket etc.

Ammunition, SA (small arms), see

Cartridges for weapons, etc.

Ammunition, smoke (water-activated

contrivances), white phosphorus,

with burster, expelling charge, or

propelling charge, see

Contrivances, water-activated, etc.

(UN0248)

Ammunition, smoke (wateractivated

contrivances), without white

phosphorus or phosphides, with

burster, expelling charge, or

propelling charge, see

Contrivances, wateractivated, etc.

(UN0249)

Ammunition smoke, white

phosphorus with burster, expelling

charge, or propelling charge

1.2H UN0245 II Prohibited Prohibited

Ammunition, smoke, white

phosphorus with burster, expelling

charge, or propelling charge

1.3H UN0246 II Prohibited Prohibited

Ammunition, smoke, with or without

burster, expelling charge, or

propelling charge

1.2G UN0015 II Prohibited Prohibited

Ammunition, smoke, with or without

burster, expelling charge, or

propelling charge

1.3G UN0016 II Prohibited Prohibited

Ammunition, smoke, with or without

burster, expelling charge, or

propelling charge

1.4G UN0303 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 181

Ammunition, sporting, see Cartridges

for weapons, etc. (UN0012;

UN0328; UN0339)

Ammunition, tearproducing,

nonexplosive, without burster or

expelling charge, non-fuzed

6.1 UN2017 II Prohibited Prohibited

Ammunition, tearproducing with

burster, expelling charge, or

propelling charge

1.2G UN0018 II Prohibited Prohibited

Ammunition, tearproducing with

burster, expelling charge, or

propelling charge

1.3G UN0019 II Prohibited Prohibited

Ammunition, tearproducing with

burster, expelling charge, or

propelling charge

1.4G UN0301 II Prohibited Prohibited

Ammunition, toxic (wateractivated

contrivances), with burster,

expelling charge, or propelling

charge, see Contrivances,

wateractivated, etc.

Ammunition, toxic, nonexplosive,

without burster or expelling charge,

nonfuzed

6.1 UN2016 II Prohibited Prohibited

Ammunition, toxic with burster,

expelling charge, or propelling

charge

1.2K UN0020 II Prohibited Prohibited

Ammunition, toxic with burster,

expelling charge, or propelling

charge

1.3K UN0021 II Prohibited Prohibited

Amyl acetates 3 UN1104 III Prohibited 3A

Amyl acid phosphate 8 UN2819 III 8A 8A

Amyl butyrates 3 UN2620 III Prohibited 3A

Amyl chlorides 3 UN1107 II Prohibited 3A

Amyl formates 3 UN1109 III Prohibited 3A

Amyl mercaptans 3 UN1111 II Prohibited Prohibited

n-Amyl methyl ketone 3 UN1110 III Prohibited 3A

Amyl nitrate 3 UN1112 III Prohibited 3A

Amyl nitrites 3 UN1113 II Prohibited 3A

Amylamines 3 UN1106 II Prohibited Prohibited

Amylamines 3 UN1106 III Prohibited 3A

Amyltrichlorosilane 8 UN1728 II Prohibited Prohibited

Anhydrous ammonia see Ammonia,

anhydrous, liquified

Anhydrous hydrofluoric acid, see

Hydrogen fluoride, anhydrous

Aniline 6.1 UN1547 II Prohibited Prohibited

Aniline hydrochloride 6.1 UN1548 III 6A 6A

Aniline oil, see Aniline

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

182 Publication 52

Anisidines 6.1 UN2431 III 6A 6A

Anisole 3 UN2222 III Prohibited 3A

Anisoyl chloride 8 UN1729 II 8A 8A

Antifreeze, liquid, see Flammable

liquids, n.o.s

Antimonous chloride, see Antimony

trichloride

Antimony compounds, inorganic,

liquid, n.o.s.

6.1 UN3141 III 6A 6A

Antimony compounds, inorganic,

solid, n.o.s.

6.1 UN1549 III 6A 6A

Antimony lactate 6.1 UN1550 III 6A 6A

Antimony pentachloride, liquid 8 UN1730 II Prohibited Prohibited

Antimony pentachloride, solutions 8 UN1731 II, III 8A 8A

Antimony pentafluoride 8 UN1732 II Prohibited Prohibited

Antimony potassium tartrate 6.1 UN1551 III 6A 6A

Antimony powder 6.1 UN2871 III 6A 6A

Antimony sulfide and a chlorate,

mixtures of

Forbidden Prohibited Prohibited Prohibited Prohibited

Antimony sulfide, solid, see Antimony

compounds, inorganic, n.o.s.

Antimony tribromide, solid 8 NA1549 II 8A 8A

Antimony tribromide, solution 8 NA1549 II 8A 8A

Antimony trichloride, liquid 8 UN1733 II 8A 8A

Antimony trichloride, solid 8 UN1733 II 8A 8A

Antimony, trifluoride, solid 8 NA1549 II 8A 8A

Antimony, trifluoride, solution 8 NA1549 II 8A 8A

Aqua ammonia, see Ammonia

solution, etc.

Argon, compressed 2.2 UN1006 n/a 2B 2B

Argon, refrigerated liquid (cryogenic

liquid)

2.2 UN1951 n/a Prohibited Prohibited

Arsenic 6.1 UN1558 II Prohibited Prohibited

Arsenic acid, liquid 6.1 UN1553 I Prohibited Prohibited

Arsenic acid, solid 6.1 UN1554 II Prohibited Prohibited

Arsenic bromide 6.1 UN1555 II Prohibited Prohibited

Arsenic chloride, see Arsenic

trichloride

Arsenic compounds, liquid, n.o.s.

inorganic, including arsenates,

n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic

compounds of arsenic, n.o.s.

6.1 UN1556 I, II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 183

Arsenic compounds, liquid, n.o.s.

inorganic, including arsenates,

n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic

compounds of arsenic, n.o.s.

6.1 UN1556 III 6A 6A

Arsenic compounds, solid, n.o.s.

inorganic, including arsenates,

n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic

compounds of arsenic, n.o.s.

6.1 UN1557 I, II Prohibited Prohibited

Arsenic compounds, solid, n.o.s.

inorganic, including arsenates,

n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic

compounds of arsenic, n.o.s.

6.1 UN1557 III 6A 6A

Arsenic pentoxide 6.1 UN1559 II Prohibited Prohibited

Arsenic sulfide 6.1 NA1557 II Prohibited Prohibited

Arsenic sulfide and a chlorate,

mixtures of

Forbidden Prohibited Prohibited Prohibited Prohibited

Arsenic trichloride 6.1 UN1560 I Prohibited Prohibited

Arsenic trioxide 6.1 UN1561 II Prohibited Prohibited

Arsenic trisulfide 6.1 NA1557 II Prohibited Prohibited

Arsenic, white, solid, see Arsenic

trioxide

Arsenical dust 6.1 UN1562 II Prohibited Prohibited

Arsenical pesticides, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2760 I, II Prohibited Prohibited

Arsenical pesticides, liquid, toxic 6.1 UN2994 I, II Prohibited Prohibited

Arsenical pesticides, liquid, toxic 6.1 UN2994 III 6A 6A

Arsenical pesticides, liquid, toxic,

flammable flashpoint not less than

23° C

6.1 UN2993 I, II Prohibited Prohibited

Arsenical pesticides, liquid, toxic,

flammable flashpoint not less than

23° C

6.1 UN2993 III 6A 6A

Arsenical pesticides, solid, toxic 6.1 UN2759 I, II Prohibited Prohibited

Arsenical pesticides, solid, toxic 6.1 UN2759 III 6A 6A

Arsenious acid, solid, see Arsenic

trioxide

Arsenious and mercuric iodide

solution, see Arsenic compounds,

liquid, n.o.s.

Arsine 2.3 UN2188 n/a Prohibited Prohibited

Articles, explosive, extremely

insensitive or Articles, EEI

1.6N UN0486 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4S UN0349 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4B UN0350 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

184 Publication 52

Articles, explosive, n.o.s. 1.4C UN0351 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4D UN0352 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4G UN0353 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.1L UN0354 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.2L UN0355 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.3L UN0356 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.1C UN0462 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.1D UN0463 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.1E UN0464 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.1F UN0465 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.2C UN0466 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.2D UN0467 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.2E UN0468 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.2F UN0469 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.3C UN0470 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4E UN0471 II Prohibited Prohibited

Articles, explosive, n.o.s. 1.4F UN0472 II Prohibited Prohibited

Articles, pressurized pneumatic or

Hydraulic containing nonflammable

gas

2.2 UN3164 n/a 2B 2B

Articles, pyrophoric 1.2L UN0380 II Prohibited Prohibited

Articles, pyrotechnic for technical

purposes

1.1G UN0428 II Prohibited Prohibited

Articles, pyrotechnic for technical

purposes

1.2G UN0429 II Prohibited Prohibited

Articles, pyrotechnic for technical

purposes

1.3G UN0430 II Prohibited Prohibited

Articles, pyrotechnic for technical

purposes

1.4G UN0431 II Prohibited Prohibited

Articles, pyrotechnic for technical

purposes

1.4S UN0432 II Prohibited Prohibited

Asbestos 9 NA2212 III Prohibited 9C

Ascaridole (organic peroxide) Forbidden Prohibited Prohibited Prohibited Prohibited

Asphalt, at or above its flashpoint 3 NA1999 III Prohibited 3A

Asphalt, cut back, see Tars, liquid,

etc.

Automobile, motorcycle, tractor,

other self-propelled vehicle, engine,

or other mechanical apparatus, see

Vehicle or Battery etc.

Aviation regulated liquid, n.o.s. 9 UN3334 n/a 9C 9C

Aviation regulated solid, n.o.s. 9 UN3335 n/a 9C 9C

Azaurolic, acid (salt of), (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Azido guanidine picrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

5-Azido-1-hydroxy tetrazole Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 185

Azido hydroxy tetrazole (mercury and

silver salts)

Forbidden Prohibited Prohibited Prohibited Prohibited

3-Azido-1,2-Propylene glycol

dinitrate

Forbidden Prohibited Prohibited Prohibited Prohibited

Azidodithiocarbonic acid Forbidden Prohibited Prohibited Prohibited Prohibited

Azidoethyl nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

1-Aziridinylphosphine oxide-(tris),

see Tris-(1aziridinyl)phosphine

oxide, solution

Azodicarbonamide 4.1 UN3242 II Prohibited 4A

Azotetrazole (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Barium 4.3 UN1400 II Prohibited 4A

Barium alloys, pyrophic 4.2 UN1854 I Prohibited Prohibited

Barium azide, dry or wetted with less

than 50 percent water, by mass

1.1A UN0224 II Prohibited Prohibited

Barium azide, wetted with not less

than 50 percent water, by mass

4.1 UN1571 I Prohibited Prohibited

Barium bromate 5.1 UN2719 II Prohibited Prohibited

Barium chlorate, solid 5.1 UN1445 II Prohibited Prohibited

Barium chlorate, solution 5.1 UN3405 II Prohibited Prohibited

Barium compounds, n.o.s. 6.1 UN1564 II Prohibited Prohibited

Barium compounds, n.o.s. 6.1 UN1564 III 6A 6A

Barium cyanide 6.1 UN1565 I Prohibited Prohibited

Barium hypochlorite with more than

percent available chlorine

5.1 UN2741 II 5A 5A

Barium nitrate 5.1 UN1446 II Prohibited Prohibited

Barium oxide 6.1 UN1884 III 6A 6A

Barium perchlorate, solid 5.1 UN1447 II Prohibited Prohibited

Barium perchlorate, solution 5.1 UN3406 II, III Prohibited Prohibited

Barium permanganate 5.1 UN1448 II Prohibited Prohibited

Barium peroxide 5.1 UN1449 II Prohibited Prohibited

Barium selenate, see Selenates or

Selenites

Barium selenite, see Selenates or

Selenites

Barium styphnate 1.1A NA0473 II Prohibited Prohibited

Batteries, containing sodium 4.3 UN3292 II Prohibited Prohibited

Batteries, dry, containing potassium

hydroxide solid, electric, storage

8 UN3028 III Prohibited Prohibited

Batteries, dry, not subject to the

requirements of 49 CFR

n/a n/a n/a Mailable

per

348.22b

Mailable

per

348.22b

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

186 Publication 52

Batteries, nickel-metal hydride see

Batteries, dry. Sealed, n.o.s. for

nickel metal hydride batteries

transported by modes other than

vessel

9 UN3496 n/a Prohibited Mailable

per

348.22b

Batteries, wet, filled with acid,

electric storage

8 UN2794 III Prohibited Prohibited

Batteries, wet, filled with

alkali,electric storage

8 UN2795 III Prohibited Prohibited

Batteries, wet, nonspillable, electric

storage

8 UN2800 III 8B 8B

Battery fluid, acid 8 UN2796 II 8A 8A

Battery fluid, alkali 8 UN2797 II 8A 8A

Battery lithium type, see Lithium

batteries etc.

Battery-powered vehicle or Battery-

powered equipment

9 UN3171 n/a Prohibited Prohibited

Battery, wet, filled with acid or alkali

with vehicle or mechanical

equipment containing internal

combustion engine) see Vehicle,

etc. or, Engines, internal

combustion etc.

Benzaldehyde 9 UN1990 III 9C 9C

Benzene 3 UN1114 II Prohibited 3A

Benzene diazonium chloride (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Benzene diazonium nitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Benzene phosphorus dichloride, see

Phenyl phosphorus dichloride

Benzene phosphorus thiodichloride,

see Phenyl phosphorus

thiodichloride

Benzene sulfonyl chloride 8 UN2225 III 8A 8A

Benzene triozonide Forbidden Prohibited Prohibited Prohibited Prohibited

Benzenethiol, see Phenyl mercaptan

Benzidine 6.1 UN1885 II Prohibited Prohibited

Benzol, see Benzene

Benzonitrile 6.1 UN2224 II Prohibited Prohibited

Benzoquinone 6.1 UN2587 II Prohibited Prohibited

Benzotrichloride 8 UN2226 II 8A 8A

Benzotrifluoride 3 UN2338 II Prohibited 3A

Benzoxidiazoles (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Benzoyl azide Forbidden Prohibited Prohibited Prohibited Prohibited

Benzoyl chloride 8 UN1736 II 8A 8A

Benzyl bromide 6.1 UN1737 II Prohibited Prohibited

Benzyl chloride 6.1 UN1738 II Prohibited Prohibited

Benzyl chloride unstabilized 6.1 UN1738 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 187

Benzyl chloroformate 8 UN1739 I Prohibited Prohibited

Benzyl iodide 6.1 UN2653 II Prohibited Prohibited

Benzyldimethylamine 8 UN2619 II 8A 8A

Benzylidene chloride 6.1 UN1886 II Prohibited Prohibited

Beryllium compounds, n.o.s. 6.1 UN1566 II Prohibited Prohibited

Beryllium compounds, n.o.s. 6.1 UN1566 III 6A 6A

Beryllium nitrate 5.1 UN2464 II Prohibited Prohibited

Beryllium, powder 6.1 UN1567 II Prohibited Prohibited

Bicyclo [2,2,1] hepta-2, 5-diene,

stabilized or 2,5-Norbornadiene,

stabilized

3 UN2251 II Prohibited 3A

Biological substance, Category B 6.2 UN3373 n/a 6C 6C

Biphenyl triozonide Forbidden Prohibited Prohibited Prohibited Prohibited

Bipyridilium pesticides, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2782 I, II Prohibited Prohibited

Bipyridilium pesticides, liquid, toxic 6.1 UN3016 I, II Prohibited Prohibited

Bipyridilium pesticides, liquid, toxic 6.1 UN3016 III 6A 6A

Bipyridilium pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN3015 I, II Prohibited Prohibited

Bipyridilium pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN3015 III 6A 6A

Bipyridilium pesticides, solid, toxic 6.1 UN2781 I, II Prohibited Prohibited

Bipyridilium pesticides, solid, toxic 6.1 UN2781 III 6A 6A

Bis (Aminopropyl) piperazine, see

Corrosive liquids, n.o.s.

Bisulfate, aqueous solution 8 UN2837 II, III 8A 8A

Bisulfites, aqueous solutions, n.o.s. 8 UN2693 III 8A 8A

Black powder, compressed or

Gunpowder, compressed or Black

powder, in pellets or Gunpowder, in

pellets

1.1D UN0028 II Prohibited Prohibited

Black powder for small arms 4.1 NA0027 I Prohibited Prohibited

Black powder or Gunpowder,

granular or as a meal

1.1D UN0027 II Prohibited Prohibited

Blasting agent, n.o.s., see

Explosives, blasting etc.

Blasting cap assemblies, see

Detonator assemblies, non-electric,

for blasting

Blasting caps, electric, see

Detonators, electric, for blasting

Blasting caps, non-electric, see

Detonators, non-electric for blasting

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

188 Publication 52

Bleaching powder, see Calcium

hypochlorite mixtures, etc.

Blue asbestos (Crocidolite) or Brown

asbestos (amosite, mysorite)

9 UN2212 II Prohibited 9C

Bombs, photo-flash 1.1F UN0037 II Prohibited Prohibited

Bombs, photo-flash 1.1D UN0038 II Prohibited Prohibited

Bombs, photo-flash 1.2G UN0039 II Prohibited Prohibited

Bombs, photo-flash 1.3G UN0299 II Prohibited Prohibited

Bombs, smoke, non-explosive, with

corrosive liquid, without initiating

device

8 UN2028 II Prohibited Prohibited

Bombs, with bursting charge 1.1F UN0033 II Prohibited Prohibited

Bombs, with bursting charge 1.1D UN0034 II Prohibited Prohibited

Bombs, with bursting charge 1.2D UN0035 II Prohibited Prohibited

Bombs, with bursting charge 1.2F UN0291 II Prohibited Prohibited

Bombs with flammable liquid, with

bursting charge

1.1J UN0399 II Prohibited Prohibited

Bombs with flammable liquid, with

bursting charge

1.2J UN0400 II Prohibited Prohibited

Boosters with detonator 1.1B UN0225 II Prohibited Prohibited

Boosters with detonator 1.2B UN0268 II Prohibited Prohibited

Boosters, without detonator 1.1D UN0042 II Prohibited Prohibited

Boosters, without detonator 1.2D UN0283 II Prohibited Prohibited

Borate and chlorate mixtures, see

Chlorate and borate mixtures

Borneol 4.1 UN1312 III Prohibited Prohibited

Boron tribromide 8 UN2692 I Prohibited Prohibited

Boron trichloride 2.3 UN1741 n/a Prohibited Prohibited

Boron trifluoride acetic acid complex,

liquid

8 UN1742 II 8A 8A

Boron trifluoride acetic acid complex,

solid

8 UN3419 II 8A 8A

Boron trifluoride 2.3 UN1008 n/a Prohibited Prohibited

Boron trifluoride diethyl etherate 8 UN2604 I Prohibited Prohibited

Boron trifluoride dihydrate 8 UN2851 II 8A 8A

Boron trifluoride dimethyl etherate 4.3 UN2965 I Prohibited Prohibited

Boron trifluoride propionic acid

complex, liquid

8 UN1743 II 8A 8A

Boron trifluoride propionic acid

complex, solid

8 UN3420 II 8A 8A

Box toe gum, see Nitrocellulose etc.

Bromates, inorganic, aqueous

solution, n.o.s.

5.1 UN3213 II 5A 5A

Bromates, inorganic, n.o.s. 5.1 UN1450 II 5A 5A

Bromine or Bromine solutions 8 UN1744 I Prohibited Prohibited

Bromine azide Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 189

Bromine chloride 2.3 UN2901 Prohibited Prohibited Prohibited

Bromine pentafluoride 5.1 UN1745 I Prohibited Prohibited

Bromine trifluoride 5.1 UN1746 I Prohibited Prohibited

4-Bromo-1,2-dinitrobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

4-Bromo-1,2-dinitrobenzene

(unstable at 59° C)

Forbidden Prohibited Prohibited Prohibited Prohibited

1-Bromo-3-chloropropane 6.1 UN2688 III 6A 6A

1-Bromo-3-methylbutane 3 UN2341 III Prohibited 3A

1-Bromo-3-nitrobenzene (unstable at

56° C)

Forbidden Prohibited Prohibited Prohibited Prohibited

Bromoacetic acid, solid 8 UN3425 II 8A 8A

Bromoacetic acid, solution 8 UN1938 II 8A 8A

Bromoacetone 6.1 UN1569 II Prohibited Prohibited

Bromoacetyl bromide 8 UN2513 II 8A 8A

Bromobenzene 3 UN2514 III Prohibited 3A

Bromobenzyl cyanides, liquid 6.1 UN1694 I Prohibited Prohibited

Bromobenzyl cyanides, solid 6.1 UN3449 I Prohibited Prohibited

1-Bromobutane 3 UN1126 II Prohibited 3A

2-Bromobutane 3 UN2339 II Prohibited 3A

Bromochloromethane 6.1 UN1887 III 6A 6A

2-Bromoethyl ethyl ether 3 UN2340 II Prohibited 3A

Bromoform 6.1 UN2515 III 6A 6A

Bromomethylpropanes 3 UN2342 II Prohibited 3A

2-Bromo-2-nitropropane-1,3-diol 4.1 UN3241 III Prohibited 4A

2-Bromopentane 3 UN2343 II Prohibited 3A

Bromopropanes 3 UN2344 II, III Prohibited 3A

3-Bromopropyne 3 UN2345 II Prohibited 3A

Bromosilane Forbidden Prohibited Prohibited Prohibited Prohibited

Bromotoluenealpha, see Benzyl

bromide

Bromotrifluoroethylene 2.1 UN2419 n/a Prohibited Prohibited

Bromotrifluoromethane or Refrigerant

gas, R 13B1

2.2 UN1009 n/a 2B 2B

Brucine 6.1 UN1570 I Prohibited Prohibited

Bursters, explosive 1.1D UN0043 II Prohibited Prohibited

Butadienes, stabilized or Butadienes

and Hydrocarbon mixture,

stabilized containing more than

percent butadienes

2.1 UN1010 n/a Prohibited 2A

Butane see also Petroleum gases,

liquified

2.1 UN1011 n/a Prohibited 2A

Butane, butane mixtures and

mixtures having similar properties in

cartridges each not exceeding

500

grams, see Receptacles, etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

190 Publication 52

Butanedione 3 UN2346 II Prohibited 3A

1,2,4-Butanetriol trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Butanols 3 UN1120 II, III Prohibited 3A

Tert-Butoxycarbonyl azide Forbidden Prohibited Prohibited Prohibited Prohibited

Butyl acetates 3 UN1123 II, III Prohibited 3A

Butyl acid phosphate 8 UN1718 III 8A 8A

Butyl acrylates, stabilized 3 UN2348 III Prohibited 3A

Butyl alcohols, see Butanols

Butyl benzenes 3 UN2709 III Prohibited 3A

n-Butyl bromide, see 1-

Bromobutane

n-Butyl chloride, see Chlorobutanes

n-Butyl chloroformate 6.1 UN2743 I Prohibited Prohibited

secButyl chloroformate 6.1 NA2742 I Prohibited Prohibited

Butyl ethers, see Dibutyl ethers

Butyl ethyl ether, see Ethyl butyl ether

n-Butyl formate 3 UN1128 II Prohibited 3A

Tert-Butyl hydroperoxide, with more

than 90 percent with water

Forbidden Prohibited Prohibited Prohibited Prohibited

Tert-Butyl hypochlorite 4.2 UN3255 I Prohibited Prohibited

N-n-Butyl imidazole 6.1 UN2690 II Prohibited Prohibited

Tert-Butyl isocyanate 6.1 UN2484 I Prohibited Prohibited

n-Butyl isocyanate 6.1 UN2485 I Prohibited Prohibited

Butyl mercaptans 3 UN2347 II Prohibited 3A

n-Butyl methacrylate, stabilized 3 UN2227 III Prohibited 3A

Butyl methyl ether 3 UN2350 II Prohibited 3A

Butyl nitrites 3 UN2351 I, II, III Prohibited 3A

tert-Butyl peroxyacetate, with more

than 76

percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

n-Butyl peroxydicarbonate, with more

than 52 percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

tert-Butyl peroxyisobutyrate, with

more than 57 percent in solution

with more than 9

percent hydrogen

peroxide, less than 26 percent

diacetone alcohol and less than

percent water; total active oxygen

content more than 9 percent by

mass

Forbidden Prohibited Prohibited Prohibited Prohibited

Diacetyl, see Butanedione

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 207

Diacetyl peroxide, solid, or with more

than 25 percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Diallylamine 3 UN2359 II Prohibited Prohibited

Diallylether 3 UN2360 II Prohibited Prohibited

4,4’-Diaminodiphenyl methane 6.1 UN2651 III 6A 6A

p-Diazidobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

1,2-Diazidoethane Forbidden Prohibited Prohibited Prohibited Prohibited

1,1’-Diazoaminonaphthalene Forbidden Prohibited Prohibited Prohibited Prohibited

Diazoaminotetrazole (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Diazodinitrophenol (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Diazodinitrophenol, wetted with not

less than 40 percent water or

mixture of alcohol and water, by

mass

1.1A UN0074 II Prohibited Prohibited

Diazodiphenylmethane Forbidden Prohibited Prohibited Prohibited Prohibited

Diazonium nitrates (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Diazonium perchlorates (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

1,3-Diazopropane Forbidden Prohibited Prohibited Prohibited Prohibited

Dibenzyl peroxydicarbonate, with

more than 87

percent with water

Forbidden Prohibited Prohibited Prohibited Prohibited

Dibenzyldichlorosilane 8 UN2434 II 8A 8A

Diborane 2.3 UN1911 n/a Prohibited Prohibited

Diborane mixtures 2.1 NA1911 n/a Prohibited Prohibited

Dibromoacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

1,2-Dibromobutan-3-one 6.1 UN2648 II Prohibited Prohibited

Dibromochloropropane 6.1 UN2872 III 6A 6A

Dibromodifluoromethane, R12B2 9 UN1941 III 9C 9C

1,2-Dibromoethane, see Ethylene

dibromide

Dibromomethane 6.1 UN2664 III 6A 6A

Dibutyl ethers 3 UN1149 III Prohibited 3B

Dibutylaminoethanol 6.1 UN2873 III 6A 6A

N,N’-Dichlorazodicarbonamidine

(salts of) (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

1,1-Dichloro-1-nitroethane 6.1 UN2650 II Prohibited Prohibited

3,5-Dichloro-2,4,6-trifluoropyridine 6.1 NA9264 I Prohibited Prohibited

Dichloroacetic acid 8 UN1764 II 8A 8A

1,3-Dichloroacetone 6.1 UN2649 II Prohibited Prohibited

Dichloroacetyl chloride 8 UN1765 II 8A 8A

Dichloroacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

Dichloroanilines, liquid 6.1 UN1590 II Prohibited Prohibited

Dichloroanilines, solid 6.1 UN3442 II Prohibited Prohibited

o-Dichlorobenzene 6.1 UN1591 III 6A 6A

Dichlorobutene 8 NA2920 I Prohibited Prohibited

2,2’-Dichlorodiethyl ether 6.1 UN1916 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

208 Publication 52

Dichlorodifluoromethane or

Refrigerant gas R 12

2.2 UN1028 n/a 2B 2B

Dichlorodifluoromethane and

difluoroethane azeotropic mixture

or Refrigerant gas R 500 with

approximately 74

percent

dichlorodifluoromethane

2.2 UN2602 n/a 2B 2B

Dichlorodimethyl ether, symmetrical 6.1 UN2249 I Prohibited Prohibited

1,1-Dichloroethane 3 UN2362 II Prohibited 3A

1,2-Dichloroethane, see Ethylene

dichloride

Dichloroethyl sulfide Forbidden Prohibited Prohibited Prohibited Prohibited

1,2-Dichloroethylene 3 UN1150 II Prohibited 3A

Dichlorofluoromethane or

Refrigerant gas R 21

2.2 UN1029 n/a 2B 2B

Dichloroisocyanuric acid, dry or

Dichloroisocyanuric acid salts

5.1 UN2465 II 5A 5A

Dichlorodisopropyl ether 6.1 UN2490 II Prohibited Prohibited

Dichloromethane 6.1 UN1593 III 6A 6A

Dichloropentanes 3 UN1152 III Prohibited 3A

Dichlorophenyl isocyanates 6.1 UN2250 II Prohibited Prohibited

Dichlorophenyltrichlorosilane 8 UN1766 II Prohibited Prohibited

1,2-Dichloropropane 3 UN1279 II Prohibited 3A

1,3-Dichloropropanol2 6.1 UN2750 II Prohibited Prohibited

Dichloropropene and propylene

dichloride mixture, see 1,2-

Dichloropropane

Dichloropropenes 3 UN2047 II, III Prohibited 3A

Dichlorosilane 2.3 UN2189 n/a Prohibited Prohibited

1,2-Dichloro-1,1,2,2-

Tetrafluoroethane or Refrigerant

gas R 114

2.2 UN1958 n/a 2B 2B

Dichlorovinylchloroarsine Forbidden Prohibited Prohibited Prohibited Prohibited

Dicycloheptadiene, see Bicyclo

[2,2,1]hepta-2,5-diene, stabilized

Dicyclohexylamine 8 UN2565 III 8A 8A

Dicyclohexylammonium nitrate 4.1 UN2687 III Prohibited 4A

Dicyclopentadiene 3 UN2048 III Prohibited 3A

Didymium nitrate 5.1 UN1465 III 5A 5A

Diesel fuel 3 NA1993

UN1202

III Prohibited 3A

Diethanol nitrosamine dinitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Diethoxymethane 3 UN2373 II Prohibited 3A

3,3-Diethoxypropene 3 UN2374 II Prohibited 3A

Diethyl carbonate 3 UN2366 III Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 209

Diethyl cellosolve, see Ethylene

glycol diethyl ether

Diethyl ether or Ethyl ether 3 UN1155 I Prohibited 3A

Diethyl ketone 3 UN1156 II Prohibited 3A

Diethyl peroxydicarbonate, with more

than 27 percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Diethyl sulfate 6.1 UN1594 II Prohibited Prohibited

Diethyl sulfide 3 UN2375 II Prohibited Prohibited

Diethylamine 3 UN1154 II Prohibited Prohibited

2-Diethylaminoethanol 8 UN2686 II Prohibited Prohibited

3-Diethylamino-propylamine 3 UN2684 III Prohibited 3A

N,N-Diethylaniline 6.1 UN2432 III 6A 6A

Diethylbenzene 3 UN2049 III Prohibited 3A

Diethyldichlorosilane 8 UN1767 II Prohibited Prohibited

Diethylene glycol dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Diethyleneglycol dinitrate,

desensitized with not less than

percent nonvolatile water-

insoluble phlegmatizer, by mass

1.1D UN0075 II Prohibited Prohibited

Diethylenetriamine 8 UN2079 II 8A 8A

N,N-Diethylethylenediamine 8 UN2685 II Prohibited Prohibited

Diethylgold bromide Forbidden Prohibited Prohibited Prohibited Prohibited

Diethylthiophosphoryl chloride 8 UN2751 II Prohibited Prohibited

Difluorochloroethanes, see 1- Chloro-

1,1-difluoroethanes

1,1-Difluoroethane or Refrigerant gas

R 152a

2.1 UN1030 n/a Prohibited 2A

1,1-Difluoroethylene or Refrigerant

gas R 1132a

2.1 UN1959 n/a Prohibited 2A

Difluoromethane or Refrigerant gas R

2.1 UN3252 n/a Prohibited 2A

Difluorophosphoric acid, anhydrous 8 UN1768 II Prohibited Prohibited

2,3-Dihydropyran 3 UN2376 II Prohibited 3A

1,8-Dihydroxy-2,4,5,7-

tetranitroanthraquinone

(chrysamminic acid)

Forbidden Prohibited Prohibited Prohibited Prohibited

Diiodoacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

Diisobutyl ketone 3 UN1157 III Prohibited 3A

Diisobutylamine 3 UN2361 III Prohibited 3A

Diisobutylene, isomeric compounds 3 UN2050 II Prohibited 3A

Diisooctyl acid phosphate 8 UN1902 III 8A 8A

Diisopropyl ether 3 UN1159 II Prohibited 3A

Diisopropylamine 3 UN1158 II Prohibited Prohibited

Diisopropylbenzene hydroperoxide,

with more than 72 percent in

solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

210 Publication 52

Diketene, stabilized 6.1 UN2521 I Prohibited Prohibited

1,2-Dimethoxyethane 3 UN2252 II Prohibited 3A

1,1-Dimethoxyethane 3 UN2377 II Prohibited 3A

Dimethyl carbonate 3 UN1161 II Prohibited 3A

Dimethyl chlorothiophosphate, see

Dimethyl thiophosphoryl chloride

2,5-Dimethyl-2,5-dihydroperoxy

hexane, with more than 82

percent

with water

Forbidden Prohibited Prohibited Prohibited Prohibited

Dimethyl disulfide 3 UN2381 II Prohibited 3A

Dimethyl ether 2.1 UN1033 n/a Prohibited 2A

Dimethyl sulfate 6.1 UN1595 I Prohibited Prohibited

Dimethyl sulfide 3 UN1164 II Prohibited Prohibited

Dimethyl thiophosphoryl chloride 6.1 UN2267 II Prohibited Prohibited

Dimethyl-N-propylamine 3 UN2266 II Prohibited Prohibited

Dimethylamine, anhydrous 2.1 UN1032 n/a Prohibited Prohibited

Dimethylamine solution 3 UN1160 II Prohibited Prohibited

2-Dimethylaminoacetonitrile 3 UN2378 II Prohibited Prohibited

2-Dimethylaminoethanol 8 UN2051 II 8A 8A

2-Dimethylaminoethyl acrylate 6.1 UN3302 II Prohibited Prohibited

2-Dimethylaminoethyl methacrylate 6.1 UN2522 II Prohibited Prohibited

N,N-Dimethylaniline 6.1 UN2253 II Prohibited Prohibited

2,3-Dimethylbutane 3 UN2457 II Prohibited 3A

1,3-Dimethylbutylamine 3 UN2379 II Prohibited Prohibited

Dimethylcardamoyl chloride 8 UN2262 II 8A 8A

Dimethylcyclohexanes 3 UN2263 II Prohibited 3A

N,N-Dimethylcyclohexlamine 8 UN2264 II 8A 8A

Dimethyldichlorosilane 3 UN1162 II Prohibited Prohibited

Dimethyldiethoxysilane 3 UN2380 II Prohibited 3A

Dimethyldioxanes 3 UN2707 II, III Prohibited 3A

N,N-Dimethylformamide 3 UN2265 III Prohibited 3A

Dimethylhexane dihydroperoxide

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Dimethylhydrazine, symmetrical 6.1 UN2382 I Prohibited Prohibited

Dimethylhydrazine, unsymmetrical 6.1 UN1163 I Prohibited Prohibited

2,2-Dimethylpropane 2.1 UN2044 n/a Prohibited 2A

Dintro-o-cresol 6.1 UN1598 II Prohibited Prohibited

1,4-Dinitro-1,1,4,4-

tetramethylolbutanetetranitrate (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

2,4-Dinitro-1,3,5-trimethylbenzene Forbidden Prohibited Prohibited Prohibited Prohibited

1,3-Dinitro-4,5-dinitrosobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

1,3-Dinitro-5,5-dimethyl hydantoin Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitro-7,8-dimethylglycoluril (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitroanilines 6.1 UN1596 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 211

Dinitrobenzenes, liquid 6.1 UN1597 II Prohibited Prohibited

Dinitrobenzenes, solid 6.1 UN3443 II Prohibited Prohibited

Dinitrochlorobenzene, see

Chlorodinitrobenzenes

1,2-Dinitroethane Forbidden Prohibited Prohibited Prohibited Prohibited

1,1-Dinitroethane (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitrogen tetroxide 2.3 UN1067 n/a Prohibited Prohibited

Dinitroglycoluril or Dingu 1.1D UN0489 II Prohibited Prohibited

Dinitromethane Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitrophenol, dry or wetted with less

than 15

percent water, by mass

1.1D UN0076 II Prohibited Prohibited

Dinitrophenel solutions 6.1 UN1599 II Prohibited Prohibited

Dinitrophenol, wetted with not less

than 15

percent water, by mass

4.1 UN1320 I Prohibited Prohibited

Dinitrophenolates alkali metals, dry or

wetted with less than 15 percent

water, by mass

1.3C UN0077 II Prohibited Prohibited

Dinitrophenolates, wetted with not

less than 15 percent water, by mass

4.1 UN1321 I Prohibited Prohibited

Dinitropropylene glycol Forbidden Prohibited Prohibited Prohibited Prohibited

2,-4Dinitroresorcinol (heavy metal

salts of) (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

4,6-Dinitroresorcinol (heavy metal

salts of) (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitroresorcinol, dry or wetted with

less than 15

percent water, by mass

1.1D UN0078 II Prohibited Prohibited

Dinitroresorcinol, wetted with not less

than 15 percent water, by mass

4.1 UN1322 I Prohibited Prohibited

3,5-Dinitrosalicylic acid (lead salt)

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitrosobenzene 1.3C UN0406 II Prohibited Prohibited

Dinitrosobenzylamidine and salts of

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

2,2-Dinitrostilbene Forbidden Prohibited Prohibited Prohibited Prohibited

Dinitrotoluenes, liquid 6.1 UN2038 II Prohibited Prohibited

Dinitrotoluenes, molten 6.1 UN1600 II Prohibited Prohibited

Dinitrotoluenes, solid 6.1 UN3454 II Prohibited Prohibited

1,9-Dinitroxy

pentamethylene2,4,6,8tetramine

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Dioxane 3 UN1165 II Prohibited 3A

Dioxolane 3 UN1166 II Prohibited 3A

Dipentene 3 UN2052 III Prohibited 3A

Diphenylamine chloroarsine 6.1 UN1698 I Prohibited Prohibited

Diphenylchloroarsine, liquid 6.1 UN1699 I Prohibited Prohibited

Diphenylchloroarsine, solid 6.1 UN3450 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

212 Publication 52

Diphenyldichlorosilane 8 UN1769 II Prohibited Prohibited

Diphenylmethyl bromide 8 UN1770 II 8A 8A

Dipicryl sulfide, dry or wetted with

less than 10 percent water, by mass

1.1D UN0401 II Prohibited Prohibited

Dipicryl sulfide, wetted with not less

than 10 percent water, by mass

4.1 UN2852 I Prohibited Prohibited

Dipicrylamine, see

Hexanitrodiphenylamine

Dipropionyl peroxide, with more than

28 percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Di-n-propyl ether 3 UN2384 II Prohibited 3A

Dipropyl ketone 3 UN2710 III Prohibited 3A

Dipropylamine 3 UN2383 II Prohibited Prohibited

Disinfectants, liquid, corrosive, n.o.s. 8 UN1903 I Prohibited Prohibited

Disinfectants, liquid, corrosive, n.o.s. 8 UN1903 II, III 8A 8A

Disinfectants, liquid, toxic, n.o.s. 6.1 UN3142 I, II Prohibited Prohibited

Disinfectants, liquid, toxic, n.o.s. 6.1 UN3142 III 6A 6A

Disinfectants, solid, toxic, n.o.s. 6.1 UN1601 II Prohibited Prohibited

Disinfectants, solid, toxic, n.o.s. 6.1 UN1601 III 6A 6A

Disodium trioxosilicate 8 UN3253 III 8A 8A

Dispersant gases, n.o.s. see

Refrigerant gases, n.o.s.

Divinyl ether, stabilized 3 UN1167 I Prohibited Prohibited

Dodecyltrichlorosilane 8 UN1771 II Prohibited Prohibited

Dry ice, see Carbon dioxide, solid

Dyes, liquid, corrosive, n.o.s. or Dye

intermediates, liquid, corrosive,

n.o.s.

8 UN2801 I Prohibited Prohibited

Dyes, liquid, corrosive, n.o.s. or Dye

intermediates, liquid, corrosive,

n.o.s.

8 UN2801 II, III 8A 8A

Dyes, liquid, toxic, n.o.s. or Dye

intermediates, liquid, toxic, n.o.s.

6.1 UN1602 II Prohibited Prohibited

Dyes, liquid, toxic, n.o.s. or Dye

intermediates, liquid, toxic, n.o.s.

6.1 UN1602 III 6A 6A

Dyes, solid, corrosive, n.o.s. or Dye

intermediates, solid, corrosive,

n.o.s.

8 UN3147 I Prohibited Prohibited

Dyes, solid, corrosive, n.o.s. or Dye

intermediates, solid, corrosive,

n.o.s.

8 UN3147 II, III 8A 8A

Dyes, solid, toxic, n.o.s. or Dye

intermediates, solid, toxic, n.o.s.

6.1 UN3143 I, II Prohibited Prohibited

Dyes, solid, toxic, n.o.s. or Dye

intermediates, solid, toxic, n.o.s.

6.1 UN3143 III 6A 6A

Dynamite, see Explosive, blasting,

type A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 213

Electrolyte (acid or alkali) for

batteries, see Battery fluid, acid or

Battery fluid, alkali

Elevated temperature liquid,

flammable, n.o.s., with flashpoint

above 37.8° C, at or above its

flashpoint

3 UN3256 III Prohibited Prohibited

Elevated temperature liquid, n.o.s., at

or above 100° C and below its

flashpoint (including molten metals,

molten salts, etc.)

9 UN3257 III Prohibited Prohibited

Elevated temperature solid, n.o.s., at

or above 240° C, see 49 CFR

173.247(h)(4)

9 UN3258 III Prohibited Prohibited

Engines, internal combustion,

flammable gas powered

9 UN3166 n/a Prohibited Prohibited

Engines, internal combustion,

flammable liquid powered

9 UN3166 n/a Prohibited Prohibited

Environmentally hazardous

substances, liquid, n.o.s.

9 UN3082 III 9C 9C

Environmentally hazardous

substances, solid, n.o.s.

9 UN3077 III 9C 9C

Epibromohydrin 6.1 UN2558 I Prohibited Prohibited

Epichlorohydrin 6.1 UN2023 II Prohibited Prohibited

1,2-Epoxy-3-ethoxypropane 3 UN2752 III Prohibited 3A

Esters, n.o.s. 3 UN3272 II, III Prohibited 3A

Etching acid, liquid, n.o.s., see

Hydrofluoric acid, solution etc.

Ethane 2.1 UN1035 n/a Prohibited 2A

EthanePropane mixture, refrigerated

liquid

2.1 NA1961 n/a Prohibited Prohibited

Ethane, refrigerated liquid 2.1 UN1961 n/a Prohibited Prohibited

Ethanol or Ethyl alcohol or Ethanol

solutions or Ethyl alcohol solutions

3 UN1170 II, III Mailable

only per

343.27

Ethanol amine dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Ethanol and gasoline mixture or

Ethanol and motor spirit mixture or

Ethanol and petrol mixture, with

more than 10% ethanol.

3 UN3475 II Prohibited Prohibited

Ethanolamine or Ethanolamine

solutions

8 UN2491 III 8A 8A

Ether, see Diethyl ether

Ethers, n.o.s. 3 UN3271 II, III Prohibited 3A

Ethyl acetate 3 UN1173 II Prohibited 3A

Ethyl acrylate, stabilized 3 UN1917 II Prohibited 3A

Ethyl alcohol, see Ethanol

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

214 Publication 52

Ethyl aldehyde, see Acetaldehyde

Ethyl amyl ketone 3 UN2271 III Prohibited 3A

N-Ethylbenzyltoluidines, solid 6.1 UN3460 III 6A 6A

N-Ethyl-N-benzylaniline 6.1 UN2274 III 6A 6A

Ethyl borate 3 UN1176 II Prohibited 3A

Ethyl bromide 6.1 UN1891 II Prohibited Prohibited

Ethyl bromoacetate 6.1 UN1603 II Prohibited Prohibited

Ethyl butyl ether 3 UN1179 II Prohibited 3A

Ethyl butyrate 3 UN1180 III Prohibited 3A

Ethyl chloride 2.1 UN1037 n/a Prohibited Prohibited

Ethyl chloroacetate 6.1 UN1181 II Prohibited Prohibited

Ethyl chloroformate 6.1 UN1182 I Prohibited Prohibited

Ethyl 2-chloropropionate 3 UN2935 III Prohibited 3A

Ethyl chlorothioformate 8 UN2826 II Prohibited Prohibited

Ethyl crotonate 3 UN1862 II Prohibited 3A

Ethyl ether, see Diethyl ether

Ethyl fluoride or Refrigerant gas

R 161

2.1 UN2453 n/a Prohibited 2A

Ethyl formate 3 UN1190 II Prohibited 3A

Ethyl hydroperoxide Forbidden Prohibited Prohibited Prohibited Prohibited

Ethyl isobutyrate 3 UN2385 II Prohibited 3A

Ethyl isocyanate 3 UN2481 I Prohibited Prohibited

Ethyl lactate 3 UN1192 III Prohibited 3A

Ethyl mercaptan 3 UN2363 I Prohibited Prohibited

Ethyl methacrylate, stabilized 3 UN2277 II Prohibited 3A

Ethyl methyl ether 2.1 UN1039 n/a Prohibited Prohibited

Ethyl methyl ketone or Methyl ethyl

ketone

3 UN1193 II Prohibited 3A

Ethyl nitrate solutions 3 UN1194 I Prohibited Prohibited

Ethyl orthoformate 3 UN2524 III Prohibited 3A

Ethyl oxalate 6.1 UN2525 III 6A 6A

Ethyl perchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Ethyl phosphonothioic dichloride,

anhydrous

6.1 NA2927 I Prohibited Prohibited

Ethyl phosphonous dichloride,

anhydrous pyrophoric liquid

6.1 NA2845 I Prohibited Prohibited

Ethyl phosphorodichloridate 6.1 NA2927 I Prohibited Prohibited

Ethyl propionate 3 UN1195 II Prohibited 3A

Ethyl propyl ether 3 UN2615 II Prohibited 3A

Ethyl silicate, see Tetraethyl silicate

Ethylacetylene, stabilized 2.1 UN2452 n/a Prohibited Prohibited

Ethylamine 2.1 UN1036 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 215

Ethylamine, aqueous solution with

not less than 50 percent but not

more than 70

percent ethylamine

3 UN2270 II Prohibited Prohibited

N-Ethylaniline 6.1 UN2272 III 6A 6A

2-Ethylaniline 6.1 UN2273 III 6A 6A

Ethylbenzene 3 UN1175 II Prohibited 3A

N-Ethylbenzyltoluidines liquid 6.1 UN2753 III 6A 6A

2-Ethylbutanol 3 UN2275 III Prohibited 3A

2-Ethylbutyl acetate 3 UN1177 III Prohibited 3A

2-Ethylbutyraldehyde 3 UN1178 II Prohibited 3A

Ethyldichloroarsine 6.1 UN1892 I Prohibited Prohibited

Ethyldichlorosilane 4.3 UN1183 I Prohibited Prohibited

Ethylene, acetylene and propylene in

mixture, refrigerated liquid with at

least 71.5

percent ethylene with not

more than 22.5 percent acetylene

and not more than 6

percent

propylene

2.1 UN3138 n/a Prohibited Prohibited

Ethylene chlorohydrin 6.1 UN1135 I Prohibited Prohibited

Ethylene 2.1 UN1962 n/a Prohibited 2A

Ethylene diamine diperchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Ethylene dibromide 6.1 UN1605 I Prohibited Prohibited

Ethylene dibromide and methyl

bromide liquid mixtures, see Methyl

bromide and ethylene dibromide

mixtures, liquid

Ethylene dichloride 3 UN1184 II Prohibited Prohibited

Ethylene glycol diethyl ether 3 UN1153 III Prohibited 3A

Ethylene glycol dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Ethylene glycol monoethyl ether 3 UN1171 III Prohibited 3A

Ethylene glycol monoethyl ether

acetate

3 UN1172 III Prohibited 3A

Ethylene glycol monomethyl ether 3 UN1188 III Prohibited 3A

Ethylene glycol monomethyl ether

acetate

3 UN1189 III Prohibited 3A

Ethylene oxide or Ethylene oxide with

nitrogen up to a total pressure of

1MPa (10 bar) at 50° C

2.3 UN1040 n/a Prohibited Prohibited

Ethylene oxide and carbon dioxide

mixtures with more than 87 percent

ethylene oxide

2.3 UN3300 n/a Prohibited Prohibited

Ethylene oxide and carbon dioxide

mixtures with more than 9

percent

but not more than 87 percent

ethylene oxide

2.1 UN1041 n/a Prohibited 2A

Ethylene oxide and carbon dioxide

mixtures with not more than

9 percent ethylene oxide

2.2 UN1952 n/a 2B 2B

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

216 Publication 52

Ethylene oxide and

chlorotetrafluoroethane mixture

with not more than 8.8

percent

ethylene oxide

2.2 UN3297 n/a 2B 2B

Ethylene oxide and

dichlorodifluoromethane mixture

with not more than 12.5 percent

ethylene oxide

2.2 UN3070 n/a 2B 2B

Ethylene oxide and

pentafluoroethane mixture with not

more than 7.9

percent ethylene

oxide

2.2 UN3298 n/a 2B 2B

Ethylene oxide and propylene oxide

mixtures with not more than

percent ethylene oxide

3 UN2983 I Prohibited Prohibited

Ethylene oxide and tetrafluoroethane

mixture with not more than

5.6

percent ethylene oxide

2.2 UN3299 n/a 2B 2B

Ethylene, refrigerated liquid

(cryogenic liquid)

2.1 UN1038 n/a Prohibited Prohibited

Ethylenediamine 8 UN1604 II 8A 8A

Ethyleneimine, stabilized 6.1 UN1185 I Prohibited Prohibited

Ethylhexaldehyde, see Octyl

aldehydes etc.

2-Ethylhexyl chloroformate 6.1 UN2748 II Prohibited Prohibited

2-Ethylhexylamine 3 UN2276 III Prohibited 3A

Ethylphenyldichlorosilane 8 UN2435 II Prohibited Prohibited

1-Ethylpiperidine 3 UN2386 II Prohibited Prohibited

N-Ethyltoluidines 6.1 UN2754 II Prohibited Prohibited

Ethyltrichlorosilane 3 UN1196 II Prohibited Prohibited

Etiologic agent, see Infectious

substances, etc.

Explosive articles, see Articles,

explosive, n.o.s. etc.

Explosive, blasting, type A 1.1D UN0081 II Prohibited Prohibited

Explosive, blasting, type B 1.1D UN0082 II Prohibited Prohibited

Explosive, blasting, type B or Agent

blasting, Type B

1.5D UN0331 II Prohibited Prohibited

Explosive, blasting, type C 1.1D UN0083 II Prohibited Prohibited

Explosive, blasting, type D 1.1D UN0084 II Prohibited Prohibited

Explosive, blasting, type E 1.1D UN0241 II Prohibited Prohibited

Explosive, blasting, type E or Agent

blasting, Type E

1.5D UN0332 II Prohibited Prohibited

Explosive, forbidden. See 49 CFR

173.54

Forbidden Prohibited Prohibited Prohibited Prohibited

Explosive substances, see

Substances, explosive, n.o.s. etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 217

Explosives, slurry, see Explosive,

blasting, type E

Explosives, water gels, see Explosive,

blasting, type E

Extracts, aromatic, liquid 3 UN1169 II, III Prohibited 3A

Extracts, flavoring, liquid 3 UN1197 II, III Prohibited 3A

Fabric with animal or vegetable oil,

see Fibers or Fabrics, etc.

Ferric arsenate 6.1 UN1606 II Prohibited Prohibited

Ferric arsenite 6.1 UN1607 II Prohibited Prohibited

Ferric chloride, anhydrous 8 UN1773 III 8A 8A

Ferric chloride, solution 8 UN2582 III 8A 8A

Ferric nitrate 5.1 UN1466 III 5A 5A

Ferrocerium 4.1 UN1323 II Prohibited 4A

Ferrosilicon, with 30 percent or more

but less than 90

percent silicon

4.3 UN1408 III Prohibited 4A

Ferrous arsenate 6.1 UN1608 II Prohibited Prohibited

Ferrous chloride, solid 8 NA1759 II 8A 8A

Ferrous chloride, solution 8 NA1760 II 8A 8A

Ferrous metal borings or Ferrous

metal shavings or Ferrous metal

turnings or Ferrous metal cuttings in

a form liable to self-heating

4.2 UN2793 III Prohibited Prohibited

Fertilizer ammoniating solution with

free ammonia

2.2 UN1043 n/a 2B 2B

Fibers, animal or Fibers, vegetable

burnt, wet or damp

4.2 UN1372 III Prohibited Prohibited

Fiber, vegetable, dry 4.1 UN3360 III Prohibited Prohibited

Fibers or Fabrics impregnated with

weakly nitrated nitrocellulose, n.o.s.

4.1 UN1353 III Prohibited Prohibited

Fibers or Fabrics, animal or vegetable

or Synthetic, n.o.s. with animal or

vegetable oil

4.2 UN1373 III Prohibited Prohibited

Films, nitrocellulose base, gelatine

coated (except scrap)

4.1 UN1324 III Prohibited Prohibited

Films, nitrocellulose base, from which

gelatine has been removed; film

scrap, see Celluloid scrap

Fire extinguisher charges, corrosive

liquid

8 UN1774 II 8A 8A

Fire extinguisher charges, expelling,

explosive, see Cartridges, power

device

Fire extinguishers containing

compressed or liquified gas

2.2 UN1044 n/a 2C 2C

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

218 Publication 52

Firelighters, solid with flammable

liquid

4.1 UN2623 III Prohibited Prohibited

Fireworks 1.1G UN0333 II Prohibited Prohibited

Fireworks 1.2G UN0334 II Prohibited Prohibited

Fireworks 1.3G UN0335 II Prohibited Prohibited

Fireworks 1.4G UN0336 II Prohibited Prohibited

Fireworks 1.4S UN0337 II Prohibited Prohibited

First aid kits 9 UN3316 Prohibited 9C

Fish meal, stabilized or Fish scrap,

stabilized

9 UN2216 III 9C 9C

Fish meal, unstabilized or Fish scrap,

unstabilized

4.2 UN1374 II Prohibited Prohibited

Flammable compressed gas (small

receptacles not fitted with a

dispersion device, not refillable), see

Receptacles, etc.

Flammable compressed gas, see

Compressed or liquified gas,

flammable, etc.

Flammable gas in lighters, see

Lighters or lighter refills, cigarettes,

containing flammable gas

Flammable liquid, toxic, corrosive,

n.o.s.

3 UN3286 I, II Prohibited Prohibited

Flammable liquids, corrosive, n.o.s. 3 UN2924 I, II Prohibited Prohibited

Flammable liquids, corrosive, n.o.s. 3 UN2924 III Prohibited 3A

Flammable liquids, n.o.s. 3 UN1993 I, II, III Prohibited 3A

Flammable liquids, toxic, n.o.s. 3 UN1992 I, II Prohibited Prohibited

Flammable liquids, toxic, n.o.s. 3 UN1992 III Prohibited 3A

Flammable solid, corrosive,

inorganic, n.o.s.

4.1 UN3180 II, III Prohibited 4A

Flammable solid, inorganic, n.o.s. 4.1 UN3178 II, III Prohibited 4A

Flammable solid, organic, molten,

n.o.s.

4.1 UN3176 II, III Prohibited 4A

Flammable solid, oxidizing, n.o.s. 4.1 UN3097 II, III Prohibited Prohibited

Flammable solid, toxic, inorganic,

n.o.s.

4.1 UN3179 II, III Prohibited 4A

Flammable solids, corrosive, organic,

n.o.s.

4.1 UN2925 II Prohibited Prohibited

Flammable solids, corrosive, organic,

n.o.s.

4.1 UN2925 III Prohibited 4A

Flammable solids, organic, n.o.s. 4.1 UN1325 II, III Prohibited 4A

Flammable solids, toxic, organic,

n.o.s.

4.1 UN2926 II Prohibited Prohibited

Flammable solids, toxic, organic,

n.o.s.

4.1 UN2926 III Prohibited 4A

Flares, aerial 1.1G UN0420 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 219

Flares, aerial 1.2G UN0421 II Prohibited Prohibited

Flares, aerial 1.3G UN0093 II Prohibited Prohibited

Flares, aerial 1.4G UN0403 II Prohibited Prohibited

Flares, aerial 1.4S UN0404 II Prohibited Prohibited

Flares, airplane, see Flares, aerial

Flares, signal, see Cartridges, signal

Flares, surface 1.1G UN0418 II Prohibited Prohibited

Flares, surface 1.2G UN0419 II Prohibited Prohibited

Flares, surface 1.3G UN0092 II Prohibited Prohibited

Flares, water-activated, see

Contrivances, water-activated, etc.

Flash powder 1.1G UN0094 II Prohibited Prohibited

Flash powder 1.3G UN0305 II Prohibited Prohibited

Flue dusts, poisonous, see Arsenical

dust

Fluoric acid, see Hydrofluoric acid,

solution, etc.

Fluorine, compressed 2.3 UN1045 n/a Prohibited Prohibited

Fluoroacetic acid 6.1 UN2642 I Prohibited Prohibited

Fluoroanilines 6.1 UN2941 III 6A 6A

Fluorobenzene 3 UN2387 II Prohibited 3A

Fluoroboric acid 8 UN1775 II 8A 8A

Fluorophosphoric acid anhydrous 8 UN1776 II Prohibited Prohibited

Fluorosilicates, n.o.s. 6.1 UN2856 III 6A 6A

Fluorosilicic acid 8 UN1778 II Prohibited Prohibited

Fluorosulfonic acid 8 UN1777 I Prohibited Prohibited

Fluorotoluenes 3 UN2388 II Prohibited 3A

Forbidden materials, see 49 CFR

173.21

Forbidden Prohibited Prohibited Prohibited Prohibited

Formaldehyde, solutions, with not

less than 25 percent formaldehyde

8 UN2209 III 8A 8A

Formaldehyde, solutions, flammable 3 UN1198 III Prohibited 3A

Formaldehyde solutions (with not

less than 10 percent and less than

percent formaldehyde), see

Aviation regulated liquide, n.o.s. or

Other regulated substances, liquid,

n.o.s.

Formalin, see Formaldehyde,

solutions, etc.

Formic acid with not less than

10 percent but not more than

percent acid by mass

8 UN3412 II Prohibited Prohibited

Formic acid with not less than

5 percent but less than 10 percent

acid by mass

8 UN3412 III 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

220 Publication 52

Formic acid 8 UN1779 II 8A 8A

Fracturing devices, explosives,

without detonators for oil wells

1.1D UN0099 II Prohibited Prohibited

Fuel, aviation, turbine engine 3 UN1863 I, II, III Prohibited 3A

Fuel cell cartridges or Fuel cell

cartridges contained in equipment

or Fuel cell cartridges packed with

equipment containing corrosive

substances

8 UN3477 8A 8A

Fuel cell cartridges or Fuel cell

cartridges contained in equipment

or Fuel cell cartridges packed with

equipment containing flammable

liquids

3 UN3473 Prohibited 3A

Fuel cell cartridges or Fuel cell

cartridges contained in equipment

or Fuel cell cartridges packed with

equipment containing hydrogen in

metal hydride

2.1 UN3479 Prohibited Prohibited Prohibited

Fuel cell cartridges or Fuel cell

cartridges contained in equipment

or Fuel cell cartridges packed with

equipment containing liquified

flammable gas

2.1 UN3478 Prohibited Prohibited Prohibited

Fuel cell cartridges or Fuel cell

cartridges contained in equipment

or Fuel cell cartridges packed with

equipment containing water-

reactive substances

4.3 UN3476 Prohibited Prohibited Prohibited

Fuel oil (No. 1, 2, 4, 5, or 6) 3 NA1993 III Prohibited 3A

Fuel system components (including

fuel control units(FCU), carburetors,

fuel lines, fuel pumps) see

Dangerous Goods in Apparatus or

Dangerous Goods in Machinery

Fulminate of mercury (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Fulminate of mercury, wet, see

Mercury fulminate, etc.

Fulminating gold Forbidden Prohibited Prohibited Prohibited Prohibited

Fulminating mercury Forbidden Prohibited Prohibited Prohibited Prohibited

Fulminating platinum Forbidden Prohibited Prohibited Prohibited Prohibited

Fulminating silver Forbidden Prohibited Prohibited Prohibited Prohibited

Fulminic acid Forbidden Prohibited Prohibited Prohibited Prohibited

Fumaryl chloride 8 UN1780 II 8A 8A

Fumigated lading, see 49 CFR

172.302(g), 173.9, and 176.76(h)

Prohibited Prohibited Prohibited Prohibited Prohibited

Fumigated transport vehicle or freight

containers see 49 CFR 173.9

Furaldehydes 6.1 UN1199 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 221

Furan 3 UN2389 I Prohibited Prohibited

Furfuryl alcohol 6.1 UN2874 III 6A 6A

Furfurylamine 3 UN2526 III Prohibited 3A

Fuse, detonating, metal clad, see

Cord, detonating, metal clad

Fuse, detonating, mild effect, metal

clad, see Cord, detonating, mild

effect, metal clad

Fuse, igniter tubular metal clad 1.4G UN0103 II Prohibited Prohibited

Fuse, non-detonating (instantaneous

or quickmatch)

1.3G UN0101 II Prohibited Prohibited

Fuse, safety 1.4S UN0105 II Prohibited 1B

Fusee (railway or highway) 4.1 NA1325 II Prohibited Prohibited

Fusel oil 3 UN1201 II, III Prohibited 3A

Fuses, tracer, see Tracers for

ammunition

Fuzes, combination, percussion and

time, see Fuzes, detonating

(UN0257, UN0367); Fuzes, igniting

(UN0317, UN0368)

Fuzes, detonating 1.1B UN0106 II Prohibited Prohibited

Fuzes, detonating 1.2B UN0107 II Prohibited Prohibited

Fuzes, detonating 1.4B UN0257 II Prohibited Prohibited

Fuzes, detonating 1.4S UN0367 II Prohibited Prohibited

Fuzes, detonating, with protective

features

1.1D UN0408 II Prohibited Prohibited

Fuzes, detonating, with protective

features

1.2D UN0409 II Prohibited Prohibited

Fuzes, detonating, with protective

features

1.4D UN0410 II Prohibited Prohibited

Fuzes, igniting 1.3G UN0316 II Prohibited Prohibited

Fuzes, igniting 1.4G UN0317 II Prohibited Prohibited

Fuzes, igniting 1.4S UN0368 II Prohibited Prohibited

Galactsan trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Gallium 8 UN2803 III Prohibited Prohibited

Gas cartridges (flammable) without a

release device, non-refillable

2.1 UN2037 n/a Prohibited 2A

Gas identification set 2.3 NA9035 n/a Prohibited Prohibited

Gas oil or Diesel fuel or Heating oil,

light

3 UN1202 III Prohibited 3A

Gas, refrigerated liquid, flammable,

n.o.s. (cryogenic liquid)

2.1 UN3312 n/a Prohibited Prohibited

Gas, refrigerated liquid, n.o.s.

(cryogenic liquid)

2.2 UN3158 n/a Prohibited Prohibited

Gas, refrigerated liquid, oxidizing,

n.o.s. (cryogenic liquid)

2.2 UN3311 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

222 Publication 52

Gas sample, nonpressurized,

flammable, n.o.s., not refrigerated

liquid

2.1 UN3167 n/a Prohibited 2A

Gas sample, nonpressurized, toxic,

flammable, n.o.s., not refrigerated

liquid

2.3 UN3168 n/a Prohibited Prohibited

Gas sample, nonpressurized, toxic,

n.o.s., not refrigerated liquid

2.3 UN3169 n/a Prohibited Prohibited

Gasohol gasoline mixed with ethyl

alcohol, with not more than

percent alcohol

3 NA1203 II Prohibited 3A

Gasoline includes gasoline mixed

with ethyl alcohol, with not more

than 10

percent alcohol

3 UN1203 II Prohibited Prohibited

Gasoline, casinghead, see Gasoline

Gelatine, blasting, see Explosive,

blasting, type A

Gelatine dynamites, see Explosive,

blasting, type A

Germane 2.3 UN2192 n/a Prohibited Prohibited

Glycerol-1,3-dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Glycerol gluconate trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Glycerol lactate trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Glycerol alpha-monochlorohydrin 6.1 UN2689 III 6A 6A

Glyceryl trinitrate, see Nitroglycerin,

etc.

Glycidaldehyde 3 UN2622 II Prohibited 3A

Grenades, hand or rifle, with bursting

charge

1.1D UN0284 II Prohibited Prohibited

Grenades, hand or rifle, with bursting

charge

1.1F UN0292 II Prohibited Prohibited

Grenades, hand or rifle, with bursting

charge

1.2D UN0285 II Prohibited Prohibited

Grenades, hand or rifle, with bursting

charge

1.2F UN0293 II Prohibited Prohibited

Grenades, illuminating, see

Ammunition, illuminating, etc.

Grenades, practice, hand or rifle 1.2G UN0372 II Prohibited Prohibited

Grenades, practice, hand or rifle 1.3G UN0318 II Prohibited Prohibited

Grenades, practice, hand or rifle 1.4G UN0452 II Prohibited Prohibited

Grenades, practice, hand or rifle 1.4S UN0110 II Prohibited Prohibited

Grenades, smoke, see Ammunition,

smoke, etc.

Guanidine nitrate 5.1 UN1467 III 5A 5A

Guanyl nitrosaminoguanylidene

hydrazine (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 223

Guanyl nitrosaminoguanylidene

hydrazine, wetted with not less than

percent water, by mass

1.1A UN0113 II Prohibited Prohibited

Guanyl nitrosaminoguanyltetrazene

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Guanyl nitrosaminoguanyltetrazene,

wetted or Tetrazene, wetted with

not less than 30

percent water or

mixture of alcohol and water, by

mass

1.1A UN0114 II Prohibited Prohibited

Gunpowder, granular or as a meal,

see Black powder, etc. (UN0027)

Gunpowder, compressed or

Gunpowder in pellets, see Black

powder, etc. (UN0028)

Hafnium powder, dry 4.2 UN2545 I, II, III Prohibited Prohibited

Hafnium powder, wetted with not

less than 25 percent water (a visible

excess of water must be present) (a)

mechanically produced, particle size

less than 53 microns; (b) chemically

produced, particle size less than

840 microns

4.1 UN1326 II Prohibited Prohibited

Hand signal device, see Signal

devices, hand

Hazardous substances, liquid or

solid, n.o.s., see Environmentally

hazardous substances, etc.

Hazardous waste, liquid, n.o.s. 9 NA3082 III Prohibited Prohibited

Hazardous waste, solid, n.o.s. 9 NA3077 III Prohibited Prohibited

Heating oil, light 3 UN1202 III Prohibited 3A

Helium, compressed 2.2 UN1046 n/a 2B 2B

Helium, refrigerated liquid (cyrogenic

liquid)

2.2 UN1963 n/a Prohibited Prohibited

Heptafluoropropane or Refrigerant

gas R 227

2.2 UN3296 n/a 2B 2B

n-Heptaldehyde 3 UN3056 III Prohibited 3A

Heptanes 3 UN1206 II Prohibited 3A

n-Heptane 3 UN2278 II Prohibited 3A

Hexachloroacetone 6.1 UN2661 III 6A 6A

Hexachlorobenzene 6.1 UN2729 III 6A 6A

Hexachlorobutadiene 6.1 UN2279 III 6A 6A

Hexachlorocyclopentadiene 6.1 UN2646 I Prohibited Prohibited

Hexachlorophene 6.1 UN2875 III 6A 6A

Hexadecyltrichlorosilane 8 UN1781 II Prohibited Prohibited

Hexadienes 3 UN2458 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

224 Publication 52

Hexaethyl tetraphosphate and

compressed gas mixtures

2.3 UN1612 n/a Prohibited Prohibited

Hexaethyl tetraphosphate, liquid 6.1 UN1611 II Prohibited Prohibited

Hexaethyl tetraphosphate, solid 6.1 UN1611 II Prohibited Prohibited

Hexafluoroacetone 2.3 UN2420 n/a Prohibited Prohibited

Hexafluoroacetone hydrate, liquid 6.1 UN2552 II Prohibited Prohibited

Hexafluoroacetone hydrate, solid 6.1 UN3436 II Prohibited Prohibited

Hexafluoroethane, compressed or

Refrigerant gas R 116

2.2 UN2193 n/a 2B 2B

Hexafluorophosphoric acid 8 UN1782 II Prohibited Prohibited

Hexafluoropropylene, compressed or

Refrigerant gas R 1216

2.2 UN1858 n/a 2B 2B

Hexaldehyde 3 UN1207 III Prohibited 3A

Hexamethylene diisocyanate 6.1 UN2281 II Prohibited Prohibited

Hexamethylene triperoxide diamine

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Hexamethylenediamine solution 8 UN1783 II Prohibited Prohibited

Hexamethylenediamine solution 8 UN1783 III 8A 8A

Hexamethylenediamine, solid 8 UN2280 III 8A 8A

Hexamethyleneimine 3 UN2493 II Prohibited Prohibited

Hexamethylenetetramine 4.1 UN1328 III Prohibited 4A

Hexamethylol benzene hexanitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanes 3 UN1208 II Prohibited 3A

2,2’,4,4’,6,6’-Hexanitro-3,3’-

dihydroxyazobenzene (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitroazoxy benzene Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitrodiphenyl urea Forbidden Prohibited Prohibited Prohibited Prohibited

N,N’-(hexanitrodiphenyl) ethylene

dinitramine (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitrodiphenylamine or

Dipicrylamine or Hexyl

1.1D UN0079 II Prohibited Prohibited

2,2’,3’,4,4’,6-

Hexanitrodiphenylamine

Forbidden Prohibited Prohibited Prohibited Prohibited

2,3’,4,4’,6,6’-Hexanitrodiphenylether Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitroethane Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitrooxanilide Forbidden Prohibited Prohibited Prohibited Prohibited

Hexanitrostilbene 1.1D UN0392 II Prohibited Prohibited

Hexanoic acid, see Corrosive liquids,

n.o.s.

Hexanols 3 UN2282 III Prohibited 3A

1-Hexene 3 UN2370 II Prohibited 3A

Hexogen and

cyclotetramethylenetetranitramine

mixtures, wetted or desensitized

see RDX and HMX mixtures, wetted

or desensitized etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 225

Hexogen and HMX mixtures, wetted

or desensitized see RDX and HMX

mixtures, wetted or desensitized

etc.

Hexogen and octogen mixtures,

wetted or desensitized see RDX and

HMX mixtures, wetted or

desensitized etc.

Hexogen, see

Cyclotrimethylenetrinitramine, etc.

Hexolite, or Hexotol dry or wetted

with less than 15 percent water, by

mass

1.1D UN0118 II Prohibited Prohibited

Hexotonal 1.1D UN0393 II Prohibited Prohibited

Hexyl, see Hexanitrodiphenylamine

Hexyltrichlorosilane 8 UN1784 II Prohibited Prohibited

High explosives, see individual

explosives’ entries

HMX, see

Cyclotetramethylenetetranitramine, etc.

Hydrazine, anhydrous or Hydrazine

aqueous solutions with more than

percent hydrazine, by mass

8 UN2029 I Prohibited Prohibited

Hydrazine, aqueous solution with not

more than 37 percent hydrazine, by

mass

6.1 UN3293 III 6A 6A

Hydrazine aqueous solution,

flammable with more than

percent hydrazine, by mass

8 UN3484 I Prohibited Prohibited

Hydrazine aqueous solution, with

more than 37 percent hydrazine, by

mass

8 UN2030 II Prohibited Prohibited

Hydrazine azide Forbidden Prohibited Prohibited Prohibited Prohibited

Hydrazine chlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Hydrazine decarbonic acid diazide Forbidden Prohibited Prohibited Prohibited Prohibited

Hydrazine perchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Hydrazine selenate Forbidden Prohibited Prohibited Prohibited Prohibited

Hydriodic acid 8 UN1787 II, III 8A 8A

Hydriodic acid, anhydrous, see

Hydrogen iodide, anhydrous

Hydrobromic acid, with more than

49 percent hydrobromic acid

8 UN1788 II, III Prohibited Prohibited

Hydrobromic acid, with not more

than 49 percent hydrobromic acid

8 UN1788 II, III 8A 8A

Hydrobromic acid, anhydrous, see

Hydrogen bromide, anhydrous

Hydrocarbon gas mixture,

compressed, n.o.s.

2.1 UN1964 n/a Prohibited 2A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

226 Publication 52

Hydrocarbon gas mixtures, liquified,

n.o.s.

2.1 UN1965 n/a Prohibited 2A

Hydrocarbons, liquid, n.o.s. 3 UN3295 I, II, III Prohibited 3A

Hydrochloric acid 8 UN1789 II, III 8A 8A

Hydrochloric acid, anhydrous, see

Hydrogen chloride, anhydrous

Hydrocyanic acid, anhydrous, see

Hydrogen cyanide, etc.

Hydrocyanic acid, aqueous solutions

or Hydrogen cyanide, aqueous

solutions with not more than

percent hydrogen cyanide

6.1 UN1613 I Prohibited Prohibited

Hydrocyanic acid, aqueous solutions

with less than 5

percent hydrogen

cyanide

6.1 NA1613 II Prohibited Prohibited

Hydrocyanic acid, liquified, see

Hydrogen cyanide, etc.

Hydrocyanic acid (prussic)

unstabilized

Forbidden Prohibited Prohibited Prohibited Prohibited

Hydrofluoric acid and Sulfuric acid

mixtures

8 UN1786 I Prohibited Prohibited

Hydrofluoric acid, anhydrous, see

Hydrogen fluoride, anhydrous

Hydrofluoric acid, with more than

60 percent strength

8 UN1790 I Prohibited Prohibited

Hydrofluoric acid, with not more than

60 percent strength

8 UN1790 II Prohibited Prohibited

Hydrofluoroboric acid, see

Fluoroboric acid

Hydorfluorosilicic acid, see

Fluorosilicic acid

Hydrogen and Methane mixtures,

compressed

2.1 UN2034 n/a Prohibited 2A

Hydrogen bromide, anhydrous 2.3 UN1048 n/a Prohibited Prohibited

Hydrogen chloride, anhydrous 2.3 UN1050 n/a Prohibited Prohibited

Hydrogen chloride, refrigerated liquid 2.3 UN2186 n/a Prohibited Prohibited

Hydrogen, compressed 2.1 UN1049 n/a Prohibited 2A

Hydrogen, cyanide, solution in

alcohol with not more than

45 percent hydrogen cyanide

6.1 UN3294 I Prohibited Prohibited

Hydrogen cyanide, stabilized with

less than 3 percent water

6.1 UN1051 I Prohibited Prohibited

Hydrogen cyanide, stabilized with

less than 3 percent water and

absorbed in a porous inert material

6.1 UN1614 I Prohibited Prohibited

Hydrogen fluoride, anhydrous 8 UN1052 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 227

Hydrogen in a metal hydride storage

system or Hydrogen in a metal

hydride storage system contained

in equipment or Hydrogen in a

metal hydride storage system

packed with equipment

2.1 UN3468 n/a Prohibited Prohibited

Hydrogen iodide, anhydrous 2.3 UN2197 n/a Prohibited Prohibited

Hydrogen iodide solution, see

Hydriodic acid, solution

Hydrogendifluoride solutions, n.o.s. 8 UN3471 II Prohibited Prohibited

Hydrogendifluoride solutions, n.o.s. 8 UN3471 III Prohibited 8A

Hydrogen peroxide and peroxyacetic

acid mixtures, stabilized with acids,

water, and not more than 5

percent

peroxyacetic acid

5.1 UN3149 II Prohibited Prohibited

Hydrogen peroxide, aqueous

solutions with more than 40

percent

but not more than 60 percent

hydrogen peroxide (stabilized as

necessary)

5.1 UN2014 II Prohibited Prohibited

Hydrogen peroxide, aqueous

solutions with not less than

percent but not more than

40 percent hydrogen peroxide

(stabilized as necessary)

5.1 UN2014 II Prohibited Prohibited

Hydrogen peroxide, aqueous

solutions with not less than

8 percent but less than 20 percent

hydrogen peroxide (stabilized as

necessary)

5.1 UN2984 III 5A 5A

Hydrogen peroxide, stabilized or

Hydrogen peroxide aqueous

solutions, stabilized with more than

percent hydrogen peroxide

5.1 UN2015 I Prohibited Prohibited

Hydrogen, refrigerated liquid

(cryogenic liquid)

2.1 UN1966 n/a Prohibited Prohibited

Hydrogen selenide, anhydrous 2.3 UN2202 n/a Prohibited Prohibited

Hydrogen sulfate, see Sulfuric acid,

etc.

Hydrogen sulfide 2.3 UN1053 n/a Prohibited Prohibited

Hydrogendifluorides, n.o.s. solid 8 UN1740 II Prohibited Prohibited

Hydrogendifluorides, n.o.s. solid 8 UN1740 III 8A 8A

Hydrogendifluorides, n.o.s. solutions 8 UN3471 II Prohibited Prohibited

Hydrogendifluorides, n.o.s. solutions 8 UN3471 III 8A 8A

Hydrosilicofluoric acid, see

Fluorosilicic acid

1-Hydroxybenzotriazole, anhydrous,

dry or wetted with less than

percent water, by mass

1.3C UN0508 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

228 Publication 52

1-Hydroxybenzotriazole,

monohydrate

4.1 UN3474 I Prohibited Prohibited

Hydroxyl amine iodide Forbidden Prohibited Prohibited Prohibited Prohibited

Hydroxylamine sulfate 8 UN2865 III 8A 8A

Hypochlorite solutions 8 UN1791 II, III 8A 8A

Hypochlorites, inorganic, n.o.s. 5.1 UN3212 II 5A 5A

Hyponitrous acid Forbidden Prohibited Prohibited Prohibited Prohibited

Igniter fuse, metal clad, see Fuse,

igniter tubular metal clad

Igniters 1.1G UN0121 II Prohibited Prohibited

Igniters 1.2G UN0314 II Prohibited Prohibited

Igniters 1.3G UN0315 II Prohibited Prohibited

Igniters 1.4G UN0325 II Prohibited Prohibited

Igniters 1.4S UN0454 II Prohibited 1A

3,3’-Iminodipropylamine 8 UN2269 III 8A 8A

Infectious substances, affecting

animals only

6.2 UN2900 n/a Prohibited Prohibited

Infectious substances, affecting

humans only

6.2 UN2814 n/a Prohibited Prohibited

Inflammable, see Flammable

Initiating explosives (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Inosital hexanitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Insecticide gases, n.o.s. 2.2 UN1968 n/a 2B 2B

Insecticide gases, flammable, n.o.s 2.1 UN3354 n/a Prohibited 2A

Insecticide gases, toxic, n.o.s. 2.3 UN1967 n/a Prohibited Prohibited

Insecticide gases, toxic, flammable,

n.o.s., Inhalation hazard A, B, C or D

2.3 UN3355 n/a Prohibited Prohibited

Inulin trinitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Iodine 8 UN3495 III Prohibited Prohibited

Iodine azide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Iodine monochloride, liquid 8 UN3498 II Prohibited Prohibited

Iodine monochloride, solid 8 UN1792 II Prohibited Prohibited

Iodine pentafluoride 5.1 UN2495 I Prohibited Prohibited

2-Iodobutane 3 UN2390 II Prohibited 3A

Iodomethylpropanes 3 UN2391 II Prohibited 3A

Iodopropanes 3 UN2392 III Prohibited 3A

Iodoxy compounds (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Iridium nitratopentamine iridium

nitrate

Forbidden Prohibited Prohibited Prohibited Prohibited

Iron chloride, see Ferric chloride, etc.

Iron oxide, spent, or Iron sponge,

spent obtained from coal gas

purification

4.2 UN1376 III Prohibited Prohibited

Iron pentacarbonyl 6.1 UN1994 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 229

Iron sesquichloride, see Ferric

chloride

Irritating material, see Tear gas

substances, etc.

Isobutane see also Petroleum gases,

liquified

2.1 UN1969 n/a Prohibited 2A

Isobutanol or Isobutyl alcohol 3 UN1212 III Prohibited 3A

Isobutyl acetate 3 UN1213 II Prohibited 3A

Isobutyl acrylate, stabilized 3 UN2527 III Prohibited 3A

Isobutyl alcohol, see Isobutanol

Isobutyl aldehyde, see

Isobutyraldehyde

Isobutyl formate 3 UN2393 II Prohibited 3A

Isobutyl isobutyrate 3 UN2528 III Prohibited 3A

Isobutyl isocyanate 3 UN2486 I Prohibited Prohibited

Isobutyl methacrylate, stabilized 3 UN2283 III Prohibited 3A

Isobutyl propionate 3 UN2394 III Prohibited 3A

Isobutylamine 3 UN1214 II Prohibited Prohibited

Isobutylene see also Petroleum

gases, liquified

2.1 UN1055 n/a Prohibited 2A

Isobutyraldehyde or Isobutyl

aldehyde

3 UN2045 II Prohibited 3A

Isobutyric acid 3 UN2529 III Prohibited 3A

Isobutyronitrile 3 UN2284 II Prohibited Prohibited

Isobutyryl chloride 3 UN2395 II Prohibited Prohibited

Isocyanates, flammable, toxic, n.o.s.

or Isocyanate solutions, flammable,

toxic, n.o.s. flashpoint less than

23°C

3 UN2478 II Prohibited Prohibited

Isocyanates, toxic, flammable, n.o.s.

or Isocyanate solutions, toxic,

flammable, n.o.s. flashpoint not less

than 23° C but not more than 61° C

and boiling point less than 300° C

6.1 UN3080 II Prohibited Prohibited

Isocyanates, toxic, n.o.s. or

Isocyanate solutions, toxic, n.o.s.

flashpoint more than 61° C and

boiling point less than 300° C

6.1 UN2206 II Prohibited Prohibited

Isocyanates, toxic, n.o.s. or

Isocyanate solutions, toxic, n.o.s.

flashpoint more than 61° C and

boiling point less than 300° C

6.1 UN2206 III 6A 6A

Isocyanatobenzotrifluorides 6.1 UN2285 II Prohibited Prohibited

Isoheptenes 3 UN2287 II Prohibited 3A

Isohexenes 3 UN2288 II Prohibited 3A

Isooctane, see Octanes

Isooctenes 3 UN1216 II Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

230 Publication 52

Isopentane, see Pentanes

Isopentanoic acid, see Corrosive

liquids, n.o.s.

Isopentenes 3 UN2371 I Prohibited 3A

Isophorone diisocyanate 6.1 UN2290 III 6A 6A

Isophoronediamine 8 UN2289 III 8A 8A

Isoprene, stabilized 3 UN1218 I Prohibited 3A

Isopropanol or Isopropyl alcohol 3 UN1219 II Prohibited 3A

Isopropenyl acetate 3 UN2403 II Prohibited 3A

Isopropenylbenzene 3 UN2303 III Prohibited 3A

Isopropyl acetate 3 UN1220 II Prohibited 3A

Isopropyl acid phosphate 8 UN1793 III 8A 8A

Isopropyl alcohol, see Isopropanol

Isopropyl butyrate 3 UN2405 III Prohibited 3A

Isopropyl chloroacetate 3 UN2947 III Prohibited 3A

Isopropyl chloroformate 6.1 UN2407 I Prohibited Prohibited

Isopropyl 2-chloropropionate 3 UN2934 III Prohibited 3A

Isopropyl isobutyrate 3 UN2406 II Prohibited 3A

Isopropyl isocyanate 3 UN2483 I Prohibited 3A

Isopropyl mercaptan, see

Propanethiols

Isopropyl nitrate 3 UN1222 II Prohibited 3A

Isopropyl phosphoric acid, see

Isopropyl acid phosphate

Isopropyl propionate 3 UN2409 II Prohibited 3A

Isopropylamine 3 UN1221 I

Isopropylbenzene 3 UN1918 III Prohibited 3A

Isopropylcumyl hydroperoxide, with

more than 72

percent in solution

Forbidden Prohibited Prohibited Prohibited Prohibited

Isosorbide dinitrate mixture with not

less than 60 percent lactose,

mannose, starch or calcium

hydrogen phosphate

4.1 UN2907 II Prohibited Prohibited

Isosorbide5mononitrate 4.1 UN3251 III Prohibited 3A

Isothiocyanic acid Forbidden Prohibited Prohibited Prohibited Prohibited

Jet fuel, see Fuel, aviation, turbine

engine

Jet, perforating guns, charged oil

well, with detonator

1.1D NA0124 II Prohibited Prohibited

Jet, perforating guns, charged oil

well, with detonator

1.4D NA0494 II Prohibited Prohibited

Jet, perforating guns, charged oil

well, without detonator

1.1D UN0124 II Prohibited Prohibited

Jet, perforating guns, charged oil

well, without detonator

1.4D UN0494 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 231

Jet, perforators, see Charges,

shaped, commercial etc.

Jet tappers, without detonator, see

Charges, shaped, commercial, etc.

Jet thrust igniters, for rocket motors

or Jato, see Igniters

Jet thrust unit (Jato), see Rockets

motors

Kerosene 3 UN1223 III Prohibited 3A

Ketones, liquid, n.o.s. 3 UN1224 I Prohibited Prohibited

Ketones, liquid, n.o.s. 3 UN1224 II, III Prohibited 3A

Krill meal 4.2 UN3497 II, III Prohibited 4A

Krypton, compressed 2.2 UN1056 n/a 2B 2B

Krypton, refrigerated liquid

(cryogenic liquid)

2.2 UN1970 n/a Prohibited Prohibited

Lacquer base or lacquer chips,

nitrocellulose, dry, see

Nitrocellulose, etc. (UN2557)

Lacquer base or lacquer chips,

plastic, wet with alcohol or solvent,

see Nitrocellulose (UN2059,

UN2555, UN2556, UN2557) or Paint

etc. (UN1263)

Lead acetate 6.1 UN1616 III 6A 6A

Lead arsenates 6.1 UN1617 II Prohibited Prohibited

Lead arsenites 6.1 UN1618 II Prohibited Prohibited

Lead azide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Lead azide, wetted with not less than

20 percent water or mixture of

alcohol and water, by mass

1.1A UN0129 II Prohibited Prohibited

Lead compounds, soluble, n.o.s. 6.1 UN2291 III 6A 6A

Lead cyanide 6.1 UN1620 II Prohibited Prohibited

Lead dioxide 5.1 UN1872 III 5A 5A

Lead dross, see Lead sulfate with

more than 3 percent free acid

Lead nitrate 5.1 UN1469 II Prohibited Prohibited

Lead nitroresorcinate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Lead perchlorate, solid 5.1 UN1470 II Prohibited Prohibited

Lead perchlorate, solution 5.1 UN3408 II, III Prohibited Prohibited

Lead peroxide, see Lead dioxide

Lead phosphite, dibasic 4.1 UN2989 II Prohibited Prohibited

Lead phosphite, dibasic 4.1 UN2989 III Prohibited 4A

Lead picrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Lead styphnate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

232 Publication 52

Lead styphnate, wetted or Lead

trinitroresorcinate, wetted with not

less than 20

percent water or

mixture of alcohol and water, by

mass

1.1A UN0130 II Prohibited Prohibited

Lead sulfate with more than

3 percent free acid

8 UN1794 II 8A 8A

Lead trinitroresorcinate, see Lead

styphnate, etc.

Lifesaving appliances, not self-

inflating containing dangerous

goods as equipment

9 UN3072 n/a Prohibited Prohibited

Lifesaving appliances, self-inflating 9 UN2990 n/a Prohibited Prohibited

Lighters, new or empty, purged of all

residual fuel and vapors

n/a

Lighter replacement cartridges

containing liquified petroleum

gases, see Lighter refills containing

flammable gas

Lighters containing flammable gas 2.1 UN1057 n/a Prohibited 3C

Lighter refills containing flammable

gas not exceeding 4 fluid ounces

(7.22 cubic inches) and 65 grams of

flammable gas

2.1 UN1057 n/a Prohibited 3C

Lighters, non-pressurized, containing

flammable liquid

3 NA1057 II Prohibited Prohibited

Lighter replacement cartridges

containing liquified petroleum gases

see Lighter refills containing

flammable gas. Etc.

Lighters, fuse 1.4S UN0131 II Prohibited Prohibited

Lime, unslaked, see Calcium oxide

Liquified gas, flammable, n.o.s. 2.1 UN3161 n/a Prohibited 2A

Liquified gas, n.o.s. 2.2 UN3163 n/a 2B 2B

Liquified gas, oxidizing, n.o.s. 2.2 UN3157 n/a 2B 2B

Liquified gas, toxic, corrosive, n.o.s.

Inhalation Hazard Zone A, B, C, or D

2.3 UN3308 n/a Prohibited Prohibited

Liquified gas, toxic, flammable,

corrosive, n.o.s. Inhalation Hazard

Zone A, B, C, or D

2.3 UN3309 n/a Prohibited Prohibited

Liquified gas, toxic, flammable, n.o.s.

Inhalation Hazard Zone A, B, C, or D

2.3 UN3160 n/a Prohibited Prohibited

Liquified gas, toxic, n.o.s. Inhalation

Hazard Zone A, B, C, or D

2.3 UN3162 n/a Prohibited Prohibited

Liquified gas, toxic, oxidizing,

corrosive, n.o.s. Inhalation Hazard

Zone A, B, C, or D

2.3 UN3310 n/a Prohibited Prohibited

Liquified gas, toxic, oxidizing, n.o.s.

Inhalation Hazard Zone A, B, C, or D

2.3 UN3307 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 233

Liquified gases, nonflammable

charged with nitrogen, carbon

dioxide, or air

2.2 UN1058 n/a 2B 2B

Liquified hydrocarbon gas, see

Hydrocarbon gas mixtures, liquified,

n.o.s., etc.

Liquified natural gas, see Methane,

etc. (UN1972)

Liquified petroleum gas, see

Petroleum gases, liquified

Lithium 4.3 UN1415 I Prohibited 4A

Lithium acetylide ethylenediamine

complex, see Water reactive solid

etc.

Lithium aluminum hydride 4.3 UN1410 I Prohibited Prohibited

Lithium aluminum hydride, ethereal 4.3 UN1411 I Prohibited Prohibited

Lithium borohydride 4.3 UN1413 I Prohibited Prohibited

Lithium ferrosilicon 4.3 UN2830 II Prohibited 4A

Lithium hydride 4.3 UN1414 I Prohibited 4A

Lithium hydride, fused solid 4.3 UN2805 II Prohibited 4A

Lithium hydroxide, monohydrate or

Lithium hydroxide, solid

8 UN2680 II 8A 8A

Lithium hydroxide, solution 8 UN2679 II, III 8A 8A

Lithium hypochlorite, dry or Lithium

hypochlorite mixtures, dryo

5.1 UN1471 II 5A 5A

Lithium-ion batteries (including

lithium polymer batteries)

9 UN3480 N/A Prohibited 9D

Lithium-ion batteries (including

lithium polymer batteries) contained

in equipment

9 UN3481 N/A 9D 9D

Lithium-ion batteries (including

lithium polymer batteries) packed

with equipment

9 UN3481 N/A 9D 9D

Lithium metal batteries (including

lithium alloy batteries)

9 UN3090 N/A Prohibited 9D

Lithium metal batteries (including

lithium alloy batteries) contained in

equipment

9 UN3091 N/A 9D 9D

Lithium metal batteries (including

lithium alloy batteries) packed with

equipment

9 UN3091 N/A 9D 9D

Lithium peroxide 5.1 UN1472 II 5A 5A

Lithium silicon 4.3 UN1417 II Prohibited 5A

LNG, see Methane etc. (UN1972)

London purple 6.1 UN1621 II 6A 6A

LPG, see Petroleum gases, liquified

Lye, see Sodium hydroxide solutions

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

234 Publication 52

Magnesium or Magnesium alloys

with more than 50

percent

magnesium in pellets, turnings, or

ribbons

4.1 UN1869 III Prohibited 4A

Magnesium aluminum phosphide 4.3 UN1419 I Prohibited Prohibited

Magnesium arsenate 6.1 UN1622 II Prohibited Prohibited

Magnesium bisulfite solution, see

Bisulfites, aqueous solutions, n.o.s.

Magnesium bromate 5.1 UN1473 II 5A 5A

Magnesium chlorate 5.1 UN2723 II 5A 5A

Magnesium diamide 4.2 UN2004 II Prohibited Prohibited

Magnesium dross, wet or hot Forbidden Prohibited Prohibited Prohibited Prohibited

Magnesium fluorosilicate 6.1 UN2853 III 6A 6A

Magnesium granules, coated particle

size not less than 149 microns

4.3 UN2950 III Prohibited Prohibited

Magnesium hydride 4.3 UN2010 I Prohibited Prohibited

Magnesium nitrate 5.1 UN1474 III 5A 5A

Magnesium perchlorate 5.1 UN1475 II 5A 5A

Magnesium peroxide 5.1 UN1476 II 5A 5A

Magnesium phosphide 4.3 UN2011 I Prohibited Prohibited

Magnesium, powder or Magnesium

alloys, powder

4.3 UN1418 I Prohibited Prohibited

Magnesium, powder or Magnesium

alloys, powder

4.3 UN1418 II, III Prohibited Prohibited

Magnesium scrap, see Magnesium

etc. (UN1869)

Magnesium silicide 4.3 UN2624 II Prohibited Prohibited

Maleic anhydride 8 UN2215 III 8A 8A

Maleic anhydride, molten 8 UN2215 III Prohibited Prohibited

Malononitrile 6.1 UN2647 II Prohibited Prohibited

Mancozeb (manganese

ethylenebisdithiocarbamate

complex with zinc) see Maneb etc.

Maneb or Maneb preparations with

not less than 60 percent maneb

4.2 UN2210 III Prohibited Prohibited

Maneb stabilized or Maneb

preparations, stabilized against self-

heating

4.3 UN2968 III Prohibited Prohibited

Manganese nitrate 5.1 UN2724 III 5A 5A

Manganese resinate 4.1 UN1330 III Prohibited 4A

Mannitan tetranitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Mannitol hexanitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Mannitol hexanitrate, wetted or

Nitromannite, wetted with not less

than 40

percent water, or mixture of

alcohol and water, by mass

1.1D UN0133 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 235

Marine pollutants, liquid or solid,

n.o.s., see Environmentally

hazardous substances, liquid or

solid, n.o.s.

Matches, block, see Matches, strike

anywhere

Matches, fusee 4.1 UN2254 III Prohibited Prohibited

Matches, safety (book, card, or strike

on box)

4.1 UN1944 III Prohibited 4B

Matches, strike anywhere 4.1 UN1331 III Prohibited Prohibited

Matches, wax, Vesta 4.1 UN1945 III Prohibited Prohibited

Matting acid, see Sulfuric acid etc.

Medicine, liquid, flammable, toxic,

n.o.s.

3 UN3248 II Prohibited Prohibited

Medicine, liquid, flammable, toxic,

n.o.s.

3 UN3248 III Prohibited 3A

Medicine, liquid, toxic, n.o.s. 6.1 UN1851 II, III 6A 6A

Medicine, solid, toxic, n.o.s. 6.1 UN3249 II, III 6A 6A

Memtetrahydrophthalic anhydride,

see Corrosive liquids, n.o.s.

Mercaptans, liquid, flammable, n.o.s.

or Mercaptan mixture, liquid,

flammable, n.o.s.

3 UN3336 I, II, III Prohibited 3A

Mercaptans, liquid, flammable, toxic,

n.o.s. or Mercaptan mixtures, liquid,

flammable, toxic, n.o.s.

3 UN1228 II Prohibited Prohibited

Mercaptans, liquid, flammable, toxic,

n.o.s. or Mercaptan mixtures, liquid,

flammable, toxic, n.o.s.

3 UN1228 III Prohibited 3A

Mercaptans, liquid, toxic, flammable,

n.o.s. or Mercaptan mixtures, liquid,

toxic, flammable, n.o.s., flashpoint

not less than 23° C

6.1 UN3071 II Prohibited Prohibited

5-Mercaptotetrazol-1-acetic acid 1.4C UN0448 II Prohibited Prohibited

Mercuric arsenate 6.1 UN1623 II Prohibited Prohibited

Mercuric chloride 6.1 UN1624 II Prohibited Prohibited

Mercuric compounds, see Mercury

compounds, etc.

Mercuric nitrate 6.1 UN1625 II Prohibited Prohibited

Mercuric potassium cyanide 6.1 UN1626 I Prohibited Prohibited

Mercuric sulfocyanate, see Mercury

thiocyanate

Mercurol, see Mercury nucleate

Mercurous azide Forbidden Prohibited Prohibited Prohibited Prohibited

Mercurous compounds, see Mercury

compounds, etc.

Mercurous nitrate 6.1 UN1627 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

236 Publication 52

Mercury 8 UN2809 III Prohibited Prohibited

Mercury acetate 6.1 UN1629 II Prohibited Prohibited

Mercury acetylide Forbidden Prohibited Prohibited Prohibited Prohibited

Mercury ammonium chloride 6.1 UN1630 II Prohibited Prohibited

Mercury based pesticides, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2778 I, II Prohibited Prohibited

Mercury based pesticides, liquid, toxic 6.1 UN3012 I, II Prohibited Prohibited

Mercury based pesticides, liquid, toxic 6.1 UN3012 III 6A 6A

Mercury based pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN3011 I, II Prohibited Prohibited

Mercury based pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN3011 III 6A 6A

Mercury based pesticides, solid, toxic 6.1 UN2777 I, II Prohibited Prohibited

Mercury based pesticides, solid, toxic 6.1 UN2777 III 6A 6A

Mercury benzoate 6.1 UN1631 II Prohibited Prohibited

Mercury bromides 6.1 UN1634 II Prohibited Prohibited

Mercury compounds, liquid, n.o.s. 6.1 UN2024 I, II Prohibited Prohibited

Mercury compounds, liquid, n.o.s. 6.1 UN2024 III 6A 6A

Mercury compounds, solid, n.o.s. 6.1 UN2025 I, II Prohibited Prohibited

Mercury compounds, solid, n.o.s. 6.1 UN2025 III 6A 6A

Mercury contained in manufactured

articles

8 UN3506 III 8C 8C

Mercury cyanide 6.1 UN1636 II Prohibited Prohibited

Mercury fulminate, wetted with not

less than 20 percent water, or

mixture of alcohol and water, by

mass

1.1A UN0135 II Prohibited Prohibited

Mercury gluconate 6.1 UN1637 II Prohibited Prohibited

Mercury iodide aquabasic

ammonobasic (Iodide of Millon’s

base)

Forbidden Prohibited Prohibited Prohibited Prohibited

Mercury iodide 6.1 UN1638 II Prohibited Prohibited

Mercury nitride Forbidden Prohibited Prohibited Prohibited Prohibited

Mercury nucleate 6.1 UN1639 II Prohibited Prohibited

Mercury oleate 6.1 UN1640 II Prohibited Prohibited

Mercury oxide 6.1 UN1641 II Prohibited Prohibited

Mercury oxycyanide, desensitized 6.1 UN1642 II Prohibited Prohibited

Mercury oxycyanide Forbidden Prohibited Prohibited Prohibited Prohibited

Mercury potassium iodide 6.1 UN1643 II Prohibited Prohibited

Mercury salicylate 6.1 UN1644 II Prohibited Prohibited

Mercury sulfates 6.1 UN1645 II Prohibited Prohibited

Mercury thiocyanate 6.1 UN1646 II Prohibited Prohibited

Mesityl oxide 3 UN1229 III Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 237

Metal carbonyls, liquid, n.o.s. 6.1 UN3281 I, II Prohibited Prohibited

Metal carbonyls, liquid, n.o.s. 6.1 UN3281 III 6A 6A

Metal carbonyls, solid, n.o.s. 6.1 UN3466 I, II Prohibited Prohibited

Metal carbonyls, solid, n.o.s. 6.1 UN3466 III 6A 6A

Metal catalyst, dry 4.2 UN2881 I, II Prohibited Prohibited

Metal catalyst, dry 4.2 UN2881 III Prohibited 4A

Metal catalyst, wetted with a visible

excess of liquid

4.2 UN1378 II Prohibited Prohibited

Metal hydrides, flammable, n.o.s. 4.1 UN3182 II, III Prohibited 3A

Metal hydrides, water reactive, n.o.s. 4.3 UN1409 I Prohibited Prohibited

Metal hydrides, water reactive, n.o.s. 4.3 UN1409 II Prohibited Prohibited

Metal powder, self-heating, n.o.s. 4.2 UN3189 II, III Prohibited Prohibited

Metal powders, flammable, n.o.s. 4.1 UN3089 II, III Prohibited 4A

Metal salts of methyl nitramine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Metal salts of organic compounds,

flammable, n.o.s.

4.1 UN3181 II, III Prohibited 4A

Metaldehyde 4.1 UN1332 III Prohibited 4A

Metallic substances, water reactive,

n.o.s.

4.3 UN3208 I, II, III Prohibited Prohibited

Metallic substance, water reactive,

self-heating, n.o.s.

4.3 UN3209 I, II, III Prohibited Prohibited

Methacrylaldehyde, inhibited 3 UN2396 II Prohibited Prohibited

Methacrylic acid, inhibited 8 UN2531 III 8A 8A

Methacrylonitrile, inhibited 3 UN3079 I Prohibited Prohibited

Methallyl alcohol 3 UN2614 III Prohibited 3A

Methane and hydrogen, mixtures, see

Hydrogen and methane, mixtures

etc.

Methane, compressed or Natural

gas, compressed (with high

methane content)

2.1 UN1971 n/a Prohibited 2A

Methane, refrigerated liquid

(cryogenic liquid) or Natural gas,

refrigerated liquid (cryogenic liquid),

with high methane content

2.1 UN1972 n/a Prohibited 2A

Methanesulfonyl chloride 6.1 UN3246 I Prohibited Prohibited

Methanol 3 UN1230 II Prohibited 3A

Methazoic acid Forbidden Prohibited Prohibited Prohibited Prohibited

4-Methoxy-4-methylpentan-2-one 3 UN2293 III Prohibited 3A

1-Methoxy-2-propanol 3 UN3092 III Prohibited 3A

Methoxymethyl isocyanate 6.1 UN2605 I Prohibited Prohibited

Methyl-2-chloropropionate 3 UN2933 III Prohibited 3A

Methyl acetate 3 UN1231 II Prohibited 3A

Methyl acetylene and propadiene

mixtures, stabilized

2.1 UN1060 n/a Prohibited 2A

Methyl acrylate, stabilized 3 UN1919 II Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

238 Publication 52

Methyl alcohol, see Methanol

Methyl allyl chloride 3 UN2554 II Prohibited 3A

Methyl amyl ketone, see Amyl methyl

ketone

Methyl bromide 2.3 UN1062 n/a Prohibited Prohibited

Methyl bromide and chloropicrin

mixtures with more than 2 percent

chloropicrin, see Chloropicrin and

methyl bromide mixtures

Methyl bromide and chloropicrin

mixtures with not more than

percent chloropicrin, see Methyl

bromide

Methyl bromide and ethylene

dibromide mixtures, liquid

6.1 UN1647 I Prohibited Prohibited

Methyl bromoacetate 6.1 UN2643 II Prohibited Prohibited

2-Methyl-1-butene 3 UN2459 I Prohibited Prohibited

2-Methyl-2-butene 3 UN2460 II Prohibited Prohibited

3-Methyl-1-butene 3 UN2561 I Prohibited Prohibited

Methyl tertbutyl ether 3 UN2398 II Prohibited 3A

Methyl butyrate 3 UN1237 II Prohibited 3A

Methyl chloride, or Refrigerant gas

2.1 UN1063 Prohibited 2A

Methyl chloride and chloropicrin

mixtures, see Chloropicrin and

methyl chloride mixtures

Methyl chloride and methylene

chloride mixtures

2.1 UN1912 n/a Prohibited 2A

Methyl chloroacetate 6.1 UN2295 I Prohibited Prohibited

Methyl chlorocarbonate, see Methyl

chloroformate

Methyl chloroform, see 1,1,1-

Trichloroethane

Methyl chloroformate 6.1 UN1238 I Prohibited Prohibited

Methyl chloromethyl ether 6.1 UN1239 I Prohibited Prohibited

Methyl dichloroacetate 6.1 UN2299 III 6A 6A

Methyl ethyl ether, see Ethyl methyl

ether

Methyl ethyl ketone peroxide, in

solution with more than 9 percent

by mass active oxygen

Forbidden Prohibited Prohibited Prohibited Prohibited

2-Methyl-5-ethylpyridine 6.1 UN2300 III 6A 6A

Methyl ethyl ketone, see Ethyl methyl

ketone

Methyl fluoride, or Refrigerant gas R

2.1 UN2454 n/a Prohibited 2A

Methyl formate 3 UN1243 I Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 239

2-Methyl-2-heptanethiol 6.1 UN3023 I Prohibited Prohibited

Methyl iodide 6.1 UN2644 I Prohibited Prohibited

Methyl isobutyl carbinol 3 UN2053 III Prohibited 3A

Methyl isobutyl ketone 3 UN1245 II Prohibited 3A

Methyl isobutyl ketone peroxide, in

solution with more than 9 percent

by mass active oxygen

Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl isocyanate 6.1 UN2480 I Prohibited Prohibited

Methyl isopropenyl ketone, inhibited 3 UN1246 II Prohibited 3A

Methyl isothiocyanate 6.1 UN2477 I Prohibited Prohibited

Methyl isovalerate 3 UN2400 II Prohibited 3A

Methyl magnesium bromide, in ethyl

ether

4.3 UN1928 I Prohibited Prohibited

Methyl mercaptan 2.3 UN1064 n/a Prohibited Prohibited

Methyl mercaptopropionaldehyde,

see 4-Thiapentanal

Methyl methacrylate monomer,

stabilized

3 UN1247 II Prohibited 3A

Methyl nitramine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl nitrite Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl norbornene dicarboxylic

anhydride, see Corrosive liquids,

n.o.s.

Methyl orthosilicate 6.1 UN2606 I Prohibited Prohibited

Methyl phosphonic dichloride 6.1 NA9206 I Prohibited Prohibited

Methyl phosphonothioic dichloride,

anhydrous, see Corrosive liquids,

n.o.s.

Methyl phosphonous dichloride,

pyrophoric liquid

6.1 NA2845 I Prohibited Prohibited

Methyl picric acid (heavy metal salts

of)

Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl propionate 3 UN1248 II Prohibited 3A

Methyl propyl ether 3 UN2612 II Prohibited 3A

Methyl propyl ketone 3 UN1249 II Prohibited 3A

Methyl sulfate, see Dimethyl sulfate

Methyl sulfide, see Dimethyl sulfide

Methyl trichloroacetate 6.1 UN2533 III 6A 6A

Methyl trimethylol methane trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Methyl vinyl ketone, stabilized 6.1 UN1251 I Prohibited Prohibited

Methylal 3 UN1234 II Prohibited Prohibited

Methylamine, anhydrous 2.1 UN1061 n/a Prohibited 2A

Methylamine, aqueous solution 3 UN1235 II Prohibited 3A

Methylamine dinitramine and dry salts

thereof

Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

240 Publication 52

Methylamine nitroform Forbidden Prohibited Prohibited Prohibited Prohibited

Methylamine perchlorate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Methylamyl acetate 3 UN1233 III Prohibited 3A

N-Methylaniline 6.1 UN2294 III 6A 6A

alpha-Methylbenzyl alcohol, solid 6.1 UN3438 III 6A 6A

alpha-Methylbenzyl alcohol, liquid 6.1 UN2937 III 6A 6A

3-Methylbutan-2-one 3 UN2397 II Prohibited 3A

N-Methylbutylamine 3 UN2945 II Prohibited Prohibited

Methylchlorosilane 2.3 UN2534 n/a Prohibited Prohibited

Methylcyclohexane 3 UN2296 II Prohibited 3A

Methylcyclohexanols, flammable 3 UN2617 III Prohibited 3A

Methylcyclohexanone 3 UN2297 III Prohibited 3A

Methylcyclopentane 3 UN2298 II Prohibited 3A

Methyldichloroarsine 6.1 NA1556 I Prohibited Prohibited

Methyldichlorosilane 4.3 UN1242 I Prohibited Prohibited

Methylene chloride, see

Dichloromethane

Methylene glycol dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

2-Methylfuran 3 UN2301 II Prohibited 3A

a-Methylglucoside tetranitrate Forbidden Prohibited Prohibited Prohibited Prohibited

a-Methylglycerol trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

5-Methylhexan-2-one 3 UN2302 III Prohibited 3A

Methylhydrazine 6.1 UN1244 I Prohibited Prohibited

4-Methylmorpholine or n-

methylmorpholine

3 UN2535 II Prohibited Prohibited

Methylpentadienes 3 UN2461 II Prohibited 3A

2-Methylpentan-2-ol 3 UN2560 III Prohibited 3A

Methylpentanes, see Hexanes

Methylphenyldichlorosilane 8 UN2437 II 8A 8A

1-Methylpiperidine 3 UN2399 II Prohibited Prohibited

Methyltetrahydrofuran 3 UN2536 II Prohibited 3A

Methyltrichlorosilane 3 UN1250 I Prohibited Prohibited

alpha-Methylvaleraldehyde 3 UN2367 II Prohibited 3A

Mine rescue equipment containing

carbon dioxide, see Carbon dioxide

Mines with bursting charge 1.1D UN0137 II Prohibited Prohibited

Mines with bursting charge 1.1F UN0136 II Prohibited Prohibited

Mines with bursting charge 1.2D UN0138 II Prohibited Prohibited

Mines with bursting charge 1.2F UN0294 II Prohibited Prohibited

Mixed acid, see Nitrating acid,

mixtures etc.

Mobility aids, see Battery powered

equipment or Battery powered

vehicle

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 241

Model rocket motor 1.4C NA0276 II Prohibited Prohibited

Model rocket motor 1.4S NA0323 II Prohibited 1A

Molybdenum pentachloride 8 UN2508 III 8A 8A

Monochloroacetone (unstabilized) Forbidden Prohibited Prohibited Prohibited Prohibited

Monochloroethylene, see Vinyl

chloride, stabilized

Monoethanolamine, see

Ethanolamine solutions

Monoethylamine, see Ethylamine

Morpholine 3 UN2054 III Prohibited 3A

Morpholine, aqueous, mixture, see

Corrosive liquids, n.o.s.

Motor fuel anti-knock compounds,

see Motor fuel anti-knock mixtures

Motor fuel anti-knock mixture,

flammable

6.1 UN3483 I Prohibited Prohibited

Motor fuel anti-knock mixtures 6.1 UN1649 I Prohibited Prohibited

Motor spirit, see Gasoline

Muriatic acid, see Hydrochloric acid

solution

Musk xylene, see 5-tert-Butyl-2,4,6-

trinitro-m-xylene

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

242 Publication 52

Naphtha see Petroleum distallates

n.o.s.

Naphthalene, crude or Naphthalene,

refined

4.1 UN1334 III Prohibited 4A

Naphthalene diozonide Forbidden Prohibited Prohibited Prohibited Prohibited

Naphthalene, molten 4.1 UN2304 III Prohibited 4A

Alpha-Naphthylamine 6.1 UN2077 III 6A 6A

Beta-Naphthylamine, solid 6.1 UN1650 II Prohibited Prohibited

Beta-Naphthylamine, solution 6.1 UN3411 II, III Prohibited Prohibited

Naphthylamineperchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Naphthylthiourea 6.1 UN1651 II Prohibited Prohibited

Naphthylurea 6.1 UN1652 II Prohibited Prohibited

Natural gases (with high methane

content), see Methane, etc.

(UN1971, UN1972)

Neohexane, see Hexanes

Neon, compressed 2.2 UN1065 n/a 2B 2B

Neon, refrigerated liquid (cryogenic

liquid)

2.2 UN1913 n/a Prohibited Prohibited

New explosive or explosive device,

see 49 CFR 173.51 and 173.56

Prohibited Prohibited Prohibited Prohibited Prohibited

Nickel carbonyl 6.1 UN1259 I Prohibited Prohibited

Nickel cyanide 6.1 UN1653 II Prohibited Prohibited

Nickel nitrate 5.1 UN2725 III 5A 5A

Nickel nitrite 5.1 UN2726 III 5A 5A

Nickel picrate Forbidden Prohibited Prohibited Prohibited Prohibited

Nicotine 6.1 UN1654 II Prohibited Prohibited

Nicotine compounds, liquid, n.o.s. or

Nicotine preparations, liquid, n.o.s.

6.1 UN3144 I, II Prohibited Prohibited

Nicotine compounds, liquid, n.o.s. or

Nicotine preparations, liquid, n.o.s.

6.1 UN3144 III 6A 6A

Nicotine compounds, solid, n.o.s. or

Nicotine preparations, solid, n.o.s.

6.1 UN1655 I, II Prohibited Prohibited

Nicotine compounds, solid, n.o.s. or

Nicotine preparations, solid, n.o.s.

6.1 UN1655 III 6A 6A

Nicotine hydrochloride liquid or

solution

6.1 UN1656 II Prohibited Prohibited

Nicotine hydrochloride, solid 6.1 UN3444 II Prohibited Prohibited

Nicotine salicylate 6.1 UN1657 II Prohibited Prohibited

Nicotine sulfate, solid 6.1 UN3445 II Prohibited Prohibited

Nicotine sulfate, solution 6.1 UN1658 II Prohibited Prohibited

Nicotine tartrate 6.1 UN1659 II Prohibited Prohibited

Nitrated paper (unstable) Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrates of diazonium compounds Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 243

Nitrates, inorganic, aqueous solution,

n.o.s.

5.1 UN3218 II, III 5A 5A

Nitrates, inorganic, n.o.s. 5.1 UN1477 II, III 5A 5A

Nitrating acid mixtures, with more

than 50

percent nitric acid

8 UN1796 I Prohibited Prohibited

Nitrating acid mixtures, with not more

than 50 percent nitric acid

8 UN1796 II Prohibited Prohibited

Nitrating acid mixtures, spent with

more than 50 percent nitric acid

8 UN1826 I Prohibited Prohibited

Nitrating acid mixtures, spent with

not more than 50

percent nitric acid

8 UN1826 II Prohibited Prohibited

Nitric acid other than red fuming, with

more than 70 percent nitric acid

8 UN2031 I Prohibited Prohibited

Nitric acid other than red fuming, with

not more than 70 percent nitric acid

8 UN2031 II Prohibited Prohibited

Nitric acid, red fuming 8 UN2032 I Prohibited Prohibited

Nitric oxide, compressed 2.3 UN1660 n/a Prohibited Prohibited

Nitric oxide and dinitrogen tetroxide

mixtures or Nitric oxide and

nitrogen dioxide mixtures

2.3 UN1975 n/a Prohibited Prohibited

Nitriles, flammable, toxic, n.o.s. 3 UN3273 I, II Prohibited Prohibited

Nitriles, toxic, flammable, n.o.s. 6.1 UN3275 I, II Prohibited Prohibited

Nitriles, toxic, liquid, n.o.s. 6.1 UN3276 I, II Prohibited Prohibited

Nitriles, toxic, liquid, n.o.s. 6.1 UN3276 III 6A 6A

Nitriles, toxic, solid, n.o.s. 6.1 UN3439 I, II, Prohibited Prohibited

Nitriles, toxic, solid, n.o.s. 6.1 UN3439 III 6A 6A

Nitrites, inorganic, aqueous solution,

n.o.s.

5.1 UN3219 II, III 5A 5A

Nitrites, inorganic, n.o.s. 5.1 UN2627 II 5A 5A

3-Nitro-4-chlorobenzotrifluoride 6.1 UN2307 II Prohibited Prohibited

Nitro isobutane triol trinitrate Forbidden Prohibited Prohibited

Nitro urea 1.1D UN0147 II Prohibited Prohibited

2-Nitro-2-methylpropanol nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

6-Nitro-4-diazotoluene-3-sulfonic

acid (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

N-Nitro-N-methylglycolamide nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

N-Nitroaniline Forbidden Prohibited Prohibited Prohibited Prohibited

Nitroanilines (o-; m-; p-;) 6.1 Prohibited Prohibited Prohibited Prohibited

Nitroanisole, liquid 6.1 UN2730 III 6A 6A

Nitroanisole, solid 6.1 UN3458 III 6A 6A

Nitrobenzene 6.1 UN1662 II Prohibited Prohibited

m-Nitrobenzene diazonium

perchlorate

Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrobenzenesulfonic acid 8 UN2305 II 8A 8A

Nitrobenzol, see Nitrobenzene

5-Nitrobenzotriazol 1.1D UN0385 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

244 Publication 52

Nitrobenzotrifluorides, liquid 6.1 UN2306 II Prohibited Prohibited

Nitrobenzotrifluorides, solid 6.1 UN3431 II Prohibited Prohibited

Nitrobromobenzenes liquid 6.1 UN2732 III 6A 6A

Nitrobromobenzenes solid 6.1 UN3459 III 6A 6A

Nitrocellulose, with not more than

12.6 percent, by dry mass mixture

with or without plasticizer, with or

without pigment

4.1 UN2557 II Prohibited 4A

Nitrocellulose, dry or wetted with less

than 25 percent water (or alcohol),

by mass

1.1D UN0340 II Prohibited Prohibited

Nitrocellulose membrane filters, with

not more than 12.6 percent

nitrogen, by dry mass

4.1 UN3270 II Prohibited 4A

Nitrocellulose, plasticized with not

less than 18 percent plasticizing

substance, by mass

1.3C UN0343 II Prohibited Prohibited

Nitrocellulose, solution, flammable

with not more than 12.6 percent

nitrogen, by mass, and not more

than 55

percent nitrocellulose

3 UN2059 II, III Prohibited 3A

Nitrocellulose, unmodified or

plasticized with less than 18

percent

plasticizing substance, by mass

1.1D UN0341 II Prohibited Prohibited

Nitrocellulose, wetted with not less

than 25

percent alcohol, by mass

1.3C UN0342 II Prohibited Prohibited

Nitrocellulose, with alcohol with not

less than 25 percent alcohol, by

mass, and with not more than

12.6

percent nitrogen, by dry mass

4.1 UN2556 II Prohibited 4A

Nitrocellulose with water with not less

than 25

percent water, by mass

4.1 UN2555 II Prohibited 4A

Nitrochlorobenzene, see

Chloronitrobenzenes etc.

Nitrocresols, solid 6.1 UN2446 III 6A 6A

Nitrocresols, liquid 6.1 UN3434 III 6A 6A

Nitroethane 3 UN2842 III Prohibited 3A

Nitroethyl nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Nitroethylene polymer Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrogen, compressed 2.2 UN1066 n/a 2B 2B

Nitrogen dioxide, see Dinitrogen

tetroxide

Nitrogen fertilizer solution, see

Fertilizer ammoniating solution etc.

Nitrogen peroxide, see Dinitrogen

tetroxide

Nitrogen, refrigerated liquid

cryogenic liquid

2.2 UN1977 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 245

Nitrogen tetroxide and nitric oxide

mixtures, see Nitric oxide and

nitrogen tetroxide mixtures

Nitrogen tetroxide, see Dinitrogen

tetroxide

Nitrogen trichloride Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrogen trifluoride, 2.2 UN2451 n/a Prohibited Prohibited

Nitrogen triiodide Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrogen triiodide monoamine Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrogen trioxide 2.3 UN2421 n/a Prohibited Prohibited

Nitroglycerin, desensitized with not

less than 40 percent non-volatile

water insoluble phlegmatizer, by

mass

1.1D UN0143 II Prohibited Prohibited

Nitroglycerin, liquid, not desensitized Forbidden Prohibited Prohibited Prohibited Prohibited

Nitroglycerin mixture, desensitized,

liquid, flammable, n.o.s. with not

more than 30

percent nitroglycerin,

by mass

3 UN3343 n/a Prohibited Prohibited

Nitroglycerin mixture, desensitized,

liquid, n.o.s. with not more than

30 percent nitroglycerin, by mass

3 UN3357 II Prohibited Prohibited

Nitroglycerin mixture, desensitized,

solid, n.o.s. with more than

2 percent but not more than

percent nitroglycerin, by mass

4.1 UN3319 II Prohibited Prohibited

Nitroglycerin, solution in alcohol, with

more than 1 percent but not more

than 5

percent nitroglycerin

3 UN3064 II Prohibited Prohibited

Nitroglycerin, solution in alcohol, with

more than 1 percent but not more

than 10

percent nitroglycerin

1.1D UN0144 II Prohibited Prohibited

Nitroglycerin, solution in alcohol, with

not more than 1 percent

nitroglycerin

3 UN1204 II Prohibited Prohibited

Nitroguanidine nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Nitroguanidine or Picrite, dry or

wetted with less than 20

percent

water, by mass

1.1D UN0282 II Prohibited Prohibited

Nitroguanidine, wetted or Picrite,

wetted with not less than 20

percent

water, by mass

4.1 UN1336 I Prohibited Prohibited

1-Nitrohydantoin Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrohydrochloric acid 8 UN1798 I Prohibited Prohibited

Nitromannite (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Nitromannite, wetted, see Mannitol

hexanitrate, etc.

Nitromethane 3 UN1261 II Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

246 Publication 52

Nitromuriatic acid, see

Nitrohydrochloric acid

Nitronaphthalene 4.1 UN2538 III Prohibited 4A

Nitophenols (o-; m-; p-;) 6.1 UN1663 III 6A 6A

m-Nitrophenyldinitro methane Forbidden Prohibited Prohibited Prohibited Prohibited

4-Nitrophenylhydrazine, with not less

than 30 percent water, by mass

4.1 UN3376 I Prohibited Prohibited

Nitropropanes 3 UN2608 III Prohibited 3A

p-Nitrosodimethylaniline 4.2 UN1369 II Prohibited Prohibited

Nitrostarch, dry or wetted with less

than 20

percent water, by mass

1.1D UN0146 II Prohibited Prohibited

Nitrostarch, wetted with not less than

20 percent water, by mass

4.1 UN1337 I Prohibited Prohibited

Nitrosugars (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Nitrosyl chloride 2.3 UN1069 n/a Prohibited Prohibited

Nitrosylsulfuric acid, liquid 8 UN2308 II 8A 8A

Nitrosylsulfuric acid, solid 8 UN3456 II 8A 8A

Nitrotoluenes, liquid 6.1 UN1664 II Prohibited Prohibited

Nitrotoluenes, solid 6.1 UN3446 II Prohibited Prohibited

Nitrotoluidines (mono) 6.1 UN2660 III 6A 6A

Nitrotriazolone or NTO 1.1D UN0490 II Prohibited Prohibited

Nitrous oxide 2.2 UN1070 n/a 2B 2B

Nitrous oxide, refrigerated liquid 2.2 UN2201 n/a Prohibited Prohibited

Nitroxylenes, liquid 6.1 UN1665 II Prohibited Prohibited

Nitroxylenes, solid 6.1 UN3447 II Prohibited Prohibited

Nitroxylol, see Nitroxylenes

Nonanes 3 UN1920 III Prohibited 3A

Non-flammable gas, n.o.s., see

Compressed gas, etc. or Liquified

gases, etc.

Nonliquified gases, see Compressed

gases, etc.

Nonliquified hydrocarbon gas, see

Hydrocarbon gas mixture,

compressed, n.o.s.

Nonyltrichlorosilane 8 UN1799 II Prohibited Prohibited

Nordhausen acid, see Sulfuric acid,

fuming etc.

2,5-Norbormadiene, stabilized, see

Bicyclo [2,2,1] hepta-2,5-diene,

stabilized

Octadecyltrichlorosilane 8 UN1800 II Prohibited Prohibited

Octadiene 3 UN2309 II Prohibited 3A

1,7-Octadiene-3,5-diyne1,8-

dimethoxy- 9-octadecynoic acid

Forbidden Prohibited Prohibited Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 247

Octafluorobut-2-ene or Refrigerant

gas R 1318

2.2 UN2422 n/a Prohibited Prohibited

Octafluorocyclobutane, or

Refrigerant gas RC 318

2.2 UN1976 n/a Prohibited Prohibited

Octafluoropropane or Refrigerant gas

R 218

2.2 UN2424 n/a Prohibited Prohibited

Octanes 3 UN1262 II Prohibited 3A

Octogen, see Cyclotetramethylene

tetranitramine, etc.

Octolite or Octol, dry or wetted with

less than 15

percent water, by mass

1.1D UN0266 II Prohibited Prohibited

Octonal 1.1D UN0496 n/a Prohibited Prohibited

Octyl aldehydes 3 UN1191 III Prohibited 3A

Octyltrichlorosilane 8 UN1801 II Prohibited Prohibited

Oil gas, compressed 2.3 UN1071 n/a Prohibited Prohibited

Oleum, see Sulfuric acid, fuming etc.

Organic peroxide, type A, liquid or

solid

Forbidden Prohibited Prohibited Prohibited Prohibited

Organic peroxide type B, liquid 5.2 UN3101 II 5A 5A

Organic peroxide type B, liquid,

temperature controlled

5.2 UN3111 II Prohibited Prohibited

Organic peroxide type B, solid 5.2 UN3102 II 5A 5A

Organic peroxide type B, solid,

temperature controlled

5.2 UN3112 II Prohibited Prohibited

Organic peroxide type C, liquid 5.2 UN3103 II 5A 5A

Organic peroxide type C, liquid,

temperature controlled

5.2 UN3113 II Prohibited Prohibited

Organic peroxide type C, solid 5.2 UN3104 II 5A 5A

Organic peroxide type C, solid,

temperature controlled

5.2 UN3114 II Prohibited Prohibited

Organic peroxide type D, liquid 5.2 UN3105 II 5A 5A

Organic peroxide type D, liquid,

temperature controlled

5.2 UN3115 II Prohibited Prohibited

Organic peroxide type D, solid 5.2 UN3106 II 5A 5A

Organic peroxide type D, solid,

temperature controlled

5.2 UN3116 II Prohibited Prohibited

Organic peroxide type E, liquid 5.2 UN3107 II 5A 5A

Organic peroxide type E, liquid,

temperature controlled

5.2 UN3117 II Prohibited Prohibited

Organic peroxide type E, solid 5.2 UN3108 II 5A 5A

Organic peroxide type E, solid,

temperature controlled

5.2 UN3118 II Prohibited Prohibited

Organic peroxide type F, liquid 5.2 UN3109 II 5A 5A

Organic peroxide type F, liquid,

temperature controlled

5.2 UN3119 II Prohibited Prohibited

Organic peroxide type F, solid 5.2 UN3110 II 5A 5A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

248 Publication 52

Organic peroxide type F, solid,

temperature controlled

5.2 UN3120 II Prohibited Prohibited

Organic phosphate, mixed with

compressed gas or Organic

phosphate compound, mixed with

compressed gas or Organic

phosphorous compound, mixed

with compressed gas

2.3 NA1955 n/a Prohibited Prohibited

Organic pigments, self-heating 4.2 UN3313 II, III Prohibited Prohibited

Organoarsenic compound, liquid,

n.o.s.

6.1 UN3280 I, II Prohibited Prohibited

Organoarsenic compound, liquid,

n.o.s.

6.1 UN3280 III 6A 6A

Organoarsenic compound, solid,

n.o.s.

6.1 UN3465 I Prohibited Prohibited

Organoarsenic compound, solid,

n.o.s.

6.1 UN3465 II, III 6A 6A

Organochlorine pesticides liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2762 I, II Prohibited Prohibited

Organochlorine pesticide, liquid,

toxic

6.1 UN2996 I, II Prohibited Prohibited

Organochlorine pesticide, liquid,

toxic

6.1 UN2996 III 6A 6A

Organochlorine pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN2995 I, II Prohibited Prohibited

Organochlorine pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN2995 III 6A 6A

Organochlorine pesticides, solid,

toxic

6.1 UN2761 I, II Prohibited Prohibited

Organochlorine pesticides, solid,

toxic

6.1 UN2761 III 6A 6A

Organometallic compound, toxic,

liquid, n.o.s.

6.1 UN3282 I, II Prohibited Prohibited

Organometallic compound, toxic,

liquid, n.o.s.

6.1 UN3282 III 6A 6A

Organometallic compound, toxic,

solid, n.o.s.

6.1 UN3467 I, II Prohibited Prohibited

Organometallic compound, toxic,

solid, n.o.s.

6.1 UN3467 III 6A 6A

Organometallic substance, liquid,

pyrophoric

4.2 UN3392 I Prohibited Prohibited

Organometallic substance, liquid,

pyro9phoric, water-reactive

4.2 UN3394 I Prohibited Prohibited

Organometallic substance, liquid,

pyrophoric, water-reactive

4.3 UN3398 I, II, III Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 249

Organometallic substance, liquid,

pyrophoric, water-reactive,

flammable

4.3 UN3399 I, II, III Prohibited Prohibited

Organometallic substance, solid,

pyrophoric

4.2 UN3391 I Prohibited Prohibited

Organometallic substance, solid,

pyrophoric, water-reactive

4.2 UN3393 I Prohibited Prohibited

Organometallic substance, solid, self

heating

4.2 UN3400 II, III Prohibited Prohibited

Organometallic substance, solid,

water-reactive

4.3 UN3395 I, II, III Prohibited Prohibited

Organometallic substance, solid,

water-reactive, flammable

4.3 UN3396 I, II, III Prohibited Prohibited

Organometallic substance, solid,

water-reactive, self-heating

4.3 UN3397 I, II, III Prohibited Prohibited

Organophosphorus compound,

toxic, flammable, n.o.s.

6.1 UN3279 I, II Prohibited Prohibited

Organophosphorus compound,

toxic, liquid, n.o.s.

6.1 UN3278 I, II Prohibited Prohibited

Organophosphorus compound,

toxic, liquid, n.o.s.

6.1 UN3278 III 6A 6A

Organophosphorus compound,

toxic, solid, n.o.s.

6.1 UN3464 I, II Prohibited Prohibited

Organophosphorus compound,

toxic, solid, n.o.s.

6.1 UN3464 III 6A 6A

Organophosphorus pesticides, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2784 I, II Prohibited Prohibited

Organophosphorus pesticides,

liquid, toxic

6.1 UN3018 I, II Prohibited Prohibited

Organophosphorus pesticides,

liquid, toxic

6.1 UN3018 III 6A 6A

Organophosphorus pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN3017 I, II Prohibited Prohibited

Organophosphorus pesticides, liquid,

toxic, flammable, flashpoint not less

than 23° C

6.1 UN3017 III 6A 6A

Organophosphorus pesticides, solid,

toxic

6.1 UN2783 I, II Prohibited Prohibited

Organophosphorus pesticides, solid,

toxic

6.1 UN2783 III 6A 6A

Organotin compounds, liquid, n.o.s. 6.1 UN2788 I, II Prohibited Prohibited

Organotin compounds, liquid, n.o.s 6.1 UN2788 III 6A 6A

Organotin compounds, solid, n.o.s. 6.1 UN3146 I, II Prohibited Prohibited

Organotin compounds, solid, n.o.s. 6.1 UN3146 III 6A 6A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

250 Publication 52

Organotin pesticides, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2787 I, II Prohibited Prohibited

Organotin pesticides, liquid, toxic 6.1 UN3020 I, II Prohibited Prohibited

Organotin pesticides, liquid, toxic 6.1 UN3020 III 6A 6A

Organotin pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN3019 I, II Prohibited Prohibited

Organotin pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN3019 III 6A 6A

Organotin pesticides, solid, toxic 6.1 UN2786 I, II Prohibited Prohibited

Organotin pesticides, solid, toxic 6.1 UN2786 III 6A 6A

Orthonitroaniline, see Nitroanilines

etc.

Osmium tetroxide 6.1 UN2471 I Prohibited Prohibited

Other regulated substances, liquid,

n.o.s.

9 NA3082 III 9C 9C

Other regulated substances, solid,

n.o.s.

9 NA3077 III 9C 9C

Oxidizing liquid, corrosive, n.o.s. 5.1 UN3098 I, II Prohibited Prohibited

Oxidizing liquid, corrosive, n.o.s. 5.1 UN3098 III 5A 5A

Oxidizing liquid, n.o.s. 5.1 UN3139 I Prohibited Prohibited

Oxidizing liquid, n.o.s. 5.1 UN3139 II, III 5A 5A

Oxidizing liquid, toxic, n.o.s. 5.1 UN3099 I, II Prohibited Prohibited

Oxidizing liquid, toxic, n.o.s. 5.1 UN3099 III 5A 5A

Oxidizing solid, corrosive, n.o.s. 5.1 UN3085 I, II Prohibited Prohibited

Oxidizing solid, corrosive, n.o.s. 5.1 UN3085 III 5A 5A

Oxidizing solid, flammable, n.o.s. 5.1 UN3137 I Prohibited Prohibited

Oxidizing solid, n.o.s. 5.1 UN1479 I Prohibited Prohibited

Oxidizing solid, n.o.s. 5.1 UN1479 II, III 5A 5A

Oxidizing solid, selfheating, n.o.s. 5.1 UN3100 II Prohibited Prohibited

Oxidizing solid, toxic, n.o.s. 5.1 UN3087 I, II Prohibited Prohibited

Oxidizing solid, toxic, n.o.s. 5.1 UN3087 III 5A 5A

Oxidizing solid, water reactive, n.o.s. 5.1 UN3121 n/a Prohibited Prohibited

Oxygen, compressed 2.2 UN1072 n/a 2B 2B

Oxygen difluoride, compressed 2.3 UN2190 n/a Prohibited Prohibited

Oxygen generator, chemical

(including when contained in

associated equipment, e.g.,

passenger service units (PSUs),

portable breathing equipment

(PBE), etc.)

5.1 UN3356 II Prohibited Prohibited

Oxygen generator, chemical, spent 9 NA3356 III Prohibited Prohibited

Oxygen, refrigerated liquid (cryogenic

liquid)

2.2 UN1073 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 251

Paint including paint, lacquer,

enamel, stain, shellac solutions,

varnish, polish, liquid filler, and

liquid lacquer base

3 UN1263 I, II, III Prohibited 3A

Paint or Paint related material 8 UN3066 II, III 8A 8A

Paint related material including paint

thinning, drying, removing, or

reducing compound

3 UN1263 I, II, III Prohibited 8A

Paint, corrosive, flammable (including

paint, lacquer, enamel, stain,

shellac, varnish, polish, liquid filler

and liquid lacquer base)

8 UN3470 II Prohibited 8A

Paint related material corrosive,

flammable (including paint thinning

or reducing compound)

8 UN3470 II Prohibited 8A

Paint, flammable, corrosive (including

paint, lacquer, enamel, stain,

shellac, varnish, polish, liquid filler

and liquid lacquer base)

3 UN3469 I, II Prohibited Prohibited

Paint, flammable, corrosive (including

paint, lacquer, enamel, stain,

shellac, varnish, polish, liquid filler

and liquid lacquer base)

3 UN3469 III Prohibited 3A

Paint related material, flammable,

corrosive (including paint thinning or

reducing compound)

3 UN3469 I, II Prohibited Prohibited

Paint related material, flammable,

corrosive (including paint thinning or

reducing compound)

3 UN3469 III Prohibited 3A

Paper, unsaturated oil treated

incompletely dried (including

carbon paper)

4.2 UN1379 III Prohibited Prohibited

Paraformaldehyde 4.1 UN2213 III Prohibited 4A

Paraldehyde 3 UN1264 III Prohibited 3A

Paranitroaniline, solid, see

Nitroanilines etc.

Parathion and compressed gas

mixture

2.3 NA1967 n/a Prohibited Prohibited

Paris green, solid, see Copper

acetoarsenite

PCB, see Polychlorinated biphenyls

Pentaporane 4.2 UN1380 I Prohibited Prohibited

Pentachloroethane 6.1 UN1669 II Prohibited Prohibited

Pentachlorophenol 6.1 UN3155 II Prohibited Prohibited

Pentaerythrite tetranitrate (dry) Forbidden Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

252 Publication 52

Pentaerythrite tetranitrate or

Pentaerythritol tetranitrate or PETN,

with not less than 7

percent wax by

mass

1.1D UN0411 II Prohibited Prohibited

Pentaerythrite tetranitrate mixture,

desensitized, solid, n.o.s. or

Pentaerythritol tetranitrate mixture,

desensitized, solid, n.o.s. or PETN

mixture, desensitized, solid,

n.o.s.,with more than 10

percent

but not more than 20

percent PETN,

by mass

4.1 UN3344 II Prohibited Prohibited

Pentaerythrite tetranitrate, wetted or

Pentaerythritol tetranitrate, wetted

or PETN, wetted with not less than

percent water, by mass, or

Pentaerythrite tetranitrate, or

Pentaerythritol tetranitrate, or

PETN, desensitized with not less

than 15

percent phlegmatizer by

mass

1.1D UN0150 II Prohibited Prohibited

Pentaerythritol tetranitrate, see

Pentaerythrite tetranitrate, etc.

Pentafluoroethane or Refrigerant gas

R 125

2.2 UN3220 n/a 2B 2B

Pentamethylheptane 3 UN2286 III Prohibited 3A

Pentane-2,4-dione 3 UN2310 III Prohibited 3A

Pentanes 3 UN1265 I, II Prohibited 3A

Pentanitroaniline (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Pentanols 3 UN1105 II, III Prohibited 3A

1-Pentene (n-amylene) 3 UN1108 I Prohibited 3A

1-Pentol 8 UN2705 II 8A 8A

Pentolite, dry or wetted with less than

15 percent water, by mass

1.1D UN0151 II Prohibited Prohibited

Pepper spray, see Aerosols, etc. or

Self-defense spray, non-

pressurized

Perchlorates, inorganic, aqueous

solution, n.o.s.

5.1 UN3211 II, III 5A 5A

Perchlorates, inorganic, n.o.s. 5.1 UN1481 II, III 5A 5A

Perchloric acid with more than

50 percent but not more than

72 percent acid, by mass

5.1 UN1873 I Prohibited Prohibited

Perchloric acid with not more than

50 percent acid by mass

8 UN1802 II Prohibited Prohibited

Perchloric acid, with more than

72 percent acid by mass

Forbidden Prohibited Prohibited Prohibited Prohibited

Perchloroethylene, see

Tetrachloroethylene

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 253

Perchloromethyl mercaptan 6.1 UN1670 I Prohibited Prohibited

Perchloryl fluoride 2.3 UN3083 n/a Prohibited Prohibited

Percussion caps, see Primers, cap

type

Perfluoro (ethyl vinyl ether) 2.1 UN3154 n/a Prohibited 2A

Perfluoro (methyl vinyl ether) 2.1 UN3153 n/a Prohibited 2A

Perfluoro-2-butene, see

Octafluorobut-2-ene

Perfumery products with flammable

solvents

3 UN1266 II, III Prohibited 3A

Permanganates, inorganic, aqueous

solution, n.o.s.

5.1 UN3214 II 5A 5A

Permanganates, inorganic, n.o.s. 5.1 UN1482 II, III 5A 5A

Peroxides, inorganic, n.o.s. 5.1 UN1483 II Prohibited Prohibited

Peroxides, inorganic, n.o.s. 5.1 UN1483 III 5A 5A

Permeation devices for calibrating air

quality monitoring equipment see

CFR 49 173.175

Peroxyacetic acid, with more than

percent and with more than

6 percent hydrogen peroxide

Forbidden Prohibited Prohibited Prohibited Prohibited

Persulfates, inorganic, aqueous

solution, n.o.s.

5.1 UN3216 III 5A 5A

Persulfates, inorganic, n.o.s. 5.1 UN3215 III 5A 5A

Pesticides, liquid, flammable, toxic,

flashpoint less than 23° C

3 UN3021 I, II Prohibited Prohibited

Pesticides, liquid, toxic, flammable,

flashpoint not less than 23° C

6.1 UN2903 I, II Prohibited Prohibited

Pesticides, liquid, toxic, flammable,

flashpoint not less than 23° C

6.1 UN2903 III 6A 6A

Pesticides, liquid, toxic, n.o.s. 6.1 UN2902 I, II Prohibited Prohibited

Pesticides, liquid, toxic, n.o.s. 6.1 UN2902 III 6A 6A

Pesticides, solid, toxic, n.o.s. 6.1 UN2588 I, II Prohibited Prohibited

Pesticides, solid, toxic, n.o.s. 6.1 UN2588 III 6A 6A

PETN, see Pentaerythrite tetranitrate

PETN/TNT, see Pentolite, etc.

Petro, see Gasoline

Petroleum crude oil 3 UN1267 I Prohibited Prohibited

Petroleum crude oil 3 UN1267 II, III Prohibited 3A

Petroleum distillates, n.o.s. or

Petroleum products, n.o.s.

3 UN1268 I, II, III Prohibited 3A

Petroleum gases, liquified or Liquified

petroleum gas

2.1 UN1075 n/a Prohibited 2A

Petroleum oil 3 NA1270 I Prohibited Prohibited

Petroleum oil 3 NA1270 II, III Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

254 Publication 52

Petroleum sour crude oil, flammable,

toxic

3 UN3494 I, II, III Prohibited Prohibited

Phenacyl bromide 6.1 UN2645 II Prohibited Prohibited

Phenetidines 6.1 UN2311 III 6A 6A

Phenol, molten 6.1 UN2312 II Prohibited Prohibited

Phenol, solid 6.1 UN1671 II Prohibited Prohibited

Phenol solutions 6.1 UN2821 II Prohibited Prohibited

Phenol solutions 6.1 UN2821 III 6A 6A

Phenolsulfonic acid, liquid 8 UN1803 II 8A 8A

Phenoxyacetic acid derivative

pesticide, liquid, flammable, toxic

flashpoint less than 23° C

3 UN3346 I, II Prohibited Prohibited

Phenoxyacetic acid derivative

pesticide, liquid, toxic

6.1 UN3348 I Prohibited Prohibited

Phenoxyacetic acid derivative

pesticide, liquid, toxic

6.1 UN3348 II, III 6A 6A

Phenoxyacetic acid derivative

pesticide, liquid, toxic, flammable,

flashpoint not less than 23° C

6.1 UN3347 I Prohibited Prohibited

Phenoxyacetic acid derivative

pesticide, liquid, toxic, flammable,

flashpoint not less than 23° C

6.1 UN3347 II, III 6A 6A

Phenoxyacetic acid derivative

pesticide, solid, toxic

6.1 UN3345 I Prohibited Prohibited

Phenoxyacetic acid derivative

pesticide, solid, toxic

6.1 UN3345 II, III 6A 6A

Phenyl chloroformate 6.1 UN2746 II Prohibited Prohibited

Phenyl isocyanate 6.1 UN2487 I Prohibited Prohibited

Phenyl mercaptan 6.1 UN2337 I Prohibited Prohibited

Phenyl phosphorus dichloride 8 UN2798 II 8A 8A

Phenyl phosphorus thiodichloride 8 UN2799 II 8A 8A

Phenyl urea pesticides, liquid, toxic 6.1 UN3002 I, II Prohibited Prohibited

Phenyl urea pesticides, liquid, toxic 6.1 UN3002 III 6A 6A

Phenylacetonitrile, liquid 6.1 UN2470 III 6A 6A

Phenylacetyl chloride 8 UN2577 II 8A 8A

Phenylcarbylamine chloride 6.1 UN1672 I Prohibited Prohibited

m-Phenylene diaminediperchlorate

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Phenylenediamines (o-; m-; p-;) 6.1 UN1673 III 6A 6A

Phenylhydrazine 6.1 UN2572 II Prohibited Prohibited

Phenylmercuric acetate 6.1 UN1674 II Prohibited Prohibited

Phenylmercuric compounds, n.o.s. 6.1 UN2026 I, II Prohibited Prohibited

Phenylmercuric compounds, n.o.s. 6.1 UN2026 III 6A 6A

Phenylmercuric hydroxide 6.1 UN1894 II Prohibited Prohibited

Phenylmercuric nitrate 6.1 UN1895 II Prohibited Prohibited

Phenyltrichlorosilane 8 UN1804 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 255

Phosgene 2.3 UN1076 Prohibited Prohibited

9-Phosphabicyclononanes or

Cyclooctadiene phosphines

4.2 UN2940 II Prohibited Prohibited

Phosphine 2.3 UN2199 Prohibited Prohibited

Phosphoric acid solution 8 UN1805 III 8A 8A

Phosphoric acid, solid 8 UN3453 III 8A 8A

Phosphoric acid triethyleneimine, see

Tris-(1-aziridinyl)phosphine oxide,

solution

Phosphorus, amorphous 4.1 UN1338 III Prohibited Prohibited

Phosphoric anhydride, see

Phosphorus pentoxide

Phosphorous acid 8 UN2834 III 8A 8A

Phosphorus bromide, see

Phosphorus tribromide

Phosphorus chloride, see

Phosphorus trichloride

Phosphorus heptasulfide, free from

yellow or white phosphorus

4.1 UN1339 II Prohibited Prohibited

Phosphorus oxybromide 8 UN1939 II Prohibited Prohibited

Phosphorus oxybromide, molten 8 UN2576 II Prohibited Prohibited

Phosphorus oxychloride 8 UN1810 II Prohibited Prohibited

Phosphorus pentabromide 8 UN2691 II 8A 8A

Phosphorus pentachloride 8 UN1806 II Prohibited Prohibited

Phosphorus pentafluoride 2.3 UN2198 Prohibited Prohibited

Phosphorus pentasulfide, free from

yellow or white phosphorus

4.3 UN1340 II Prohibited 4A

Phosphorus pentoxide 8 UN1807 II 8A 8A

Phosphorus sesquisulfide, free from

yellow or white phosphorus

4.1 UN1341 II Prohibited Prohibited

Phosphorus tribromide 8 UN1808 II Prohibited Prohibited

Phosphorus trichloride 6.1 UN1809 I Prohibited Prohibited

Phosphorus trioxide 8 UN2578 III 8A 8A

Phosphorus trisulfide, free from

yellow or white phosphorus

4.1 UN1343 II Prohibited Prohibited

Phosphorus, white dry or

Phosphorus, white, under water or

Phosphorus white, in solution or

Phosphorus, yellow dry or

Phosphorus, yellow, under water or

Phosphorus, yellow, in solution

4.2 UN1381 I Prohibited Prohibited

Phosphorus white, molten 4.2 UN2447 I Prohibited Prohibited

Phosphorus (white or red) and a

chlorate, mixtures of

Forbidden Prohibited Prohibited Prohibited Prohibited

Phosphoryl chloride, see

Phosphorus

oxychloride

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

256 Publication 52

Phthalic anhydride with more than

.05 percent maleic anhydride

8 UN2214 III 8A 8A

Picolines 3 UN2313 III Prohibited 3A

Picric acid, see Trinitrophenol, etc.

Picrite, see Nitroguanidine, etc.

Picryl chloride, see

Trinitrochlorobenzene

Pine oil 3 UN1272 III Prohibited 3A

alphaPinene 3 UN2368 III Prohibited 3A

Piperazine 8 UN2579 III 8A 8A

Piperidine 8 UN2401 I Prohibited Prohibited

Pivaloyl chloride, see Trimethylacetyl

chloride

Plastic molding compound in dough,

sheet, or extruded rope form

evolving flammable vapor

9 UN3314 III Prohibited 9C

Plastic solvent, n.o.s., see Flammable

liquids, n.o.s.

Plastics, nitrocellulose-based, self-

heating, n.o.s.

4.2 UN2006 III Prohibited Prohibited

Poisonous gases, n.o.s., see

Compressed or Liquified gases,

flammable or toxic, n.o.s.

Polyalkylamines, n.o.s., see Amines,

etc.

Polyamines, flammable, corrosive,

n.o.s. see Amines, flammable,

corrosive, n.o.s.

Polyamines, liquid, corrosive, n.o.s.

see Amines, liquid, corrosive, n.o.s.

Polyamines, liquid, corrosive,

flammable, n.o.s. see Amines,

liquid, corrosive, flammable, n.o.s.

Polychlorinated biphenyls, liquid 9 UN2315 II Prohibited 9C

Polychlorinated biphenyls, solid 9 UN3432 II Prohibited 9C

Polyester resin kit 3 UN3269 n/a Prohibited 3A

Polyhalogenated biphenyls, liquid or

Polyhalogenated terphenyls, liquid

9 UN3151 II Prohibited 9C

Polyhalogenated biphenyls, solid or

Polyhalogenated terphenyls, solid

9 UN3152 II Prohibited 9C

Polymeric beads, expandable,

evolving flammable vapor

9 UN2211 III Prohibited 9C

Potassium 4.3 UN2257 I Prohibited Prohibited

Potassium arsenate 6.1 UN1677 II Prohibited Prohibited

Potassium arsenite 6.1 UN1678 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 257

Potassium bisulfite solution, see

Bisulfites, inorganic, aqueous

solutions, n.o.s.

Potassium borohydride 4.3 UN1870 I Prohibited Prohibited

Potassium bromate 5.1 UN1484 II 5A 5A

Potassium carbonyl Forbidden Prohibited Prohibited Prohibited Prohibited

Potassium chlorate 5.1 UN1485 II 5A 5A

Potassium chlorate mixed with

mineral oil, see Explosive, blasting,

type C

Potassium chlorate, aqueous

solution

5.1 UN2427 II, III 5A 5A

Potassium cuprocyanide 6.1 UN1679 II Prohibited Prohibited

Potassium cyanide, solid 6.1 UN1680 I Prohibited Prohibited

Potassium cyanide solution 6.1 UN3413 I Prohibited Prohibited

Potassium dichloro isocyanurate or

Potassium dichloro-s-triazinetrione,

see Dichloroisocyanuric acid, dry or

Dichloroisocyanuric acid salts etc.

Potassium dithionite or Potassium

hydrosulfite

4.2 UN1929 II Prohibited Prohibited

Potassium fluoride, solid 6.1 UN1812 III 6A 6A

Potassium fluoride solution 6.1 UN3422 III 6A 6A

Potassium fluoroacetate 6.1 UN2628 I Prohibited Prohibited

Potassium fluorosilicate 6.1 UN2655 III 6A 6A

Potassium hydrate, see Potassium

hydroxide, solid

Potassium hydrogen fluoride

solution, see Corrosive liquid, n.o.s.

Potassium hydrogen fluoride, see

Potassium hydrogen difluoride

Potassium hydrogen sulfate 8 UN2509 II 8A 8A

Potassium hydrogendifluoride, solid 8 UN1811 II 8A 8A

Potassium hydrogendifluoride,

solution

8 UN3421 II 8A 8A

Potassium hydrosulfite, see

Potassium dithionite

Potassium hydroxide, liquid, see

Potassium hydroxide solution

Potassium hydroxide, solid 8 UN1813 II 8A 8A

Potassium hydroxide, solution 8 UN1814 II, III 8A 8A

Potassium hypochlorite, solution, see

Hypochlorite solutions

Potassium, metal alloys, liquid 4.3 UN1420 I Prohibited 4A

Potassium, metal alloys, solid 4.3 UN3403 I Prohibited Prohibited

Potassium metavanadate 6.1 UN2864 II Prohibited Prohibited

Potassium monoxide 8 UN2033 II 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

258 Publication 52

Potassium nitrate 5.1 UN1486 III 5A 5A

Potassium nitrate and sodium nitrite

mixtures

5.1 UN1487 II 5A 5A

Potassium nitrite 5.1 UN1488 II 5A 5A

Potassium perchlorate 5.1 UN1489 II 5A 5A

Potassium permanganate 5.1 UN1490 II 5A 5A

Potassium peroxide 5.1 UN1491 I Prohibited Prohibited

Potassium persulfate 5.1 UN1492 III 5A 5A

Potassium phosphide 4.3 UN2012 I Prohibited Prohibited

Potassium selenate, see Selenates or

Selenites

Potassium selenite, see Selenates or

Selenites

Potassium sodium alloys, liquid 4.3 UN1422 I Prohibited Prohibited

Potassium sodium alloys, solid 4.3 UN3404 I Prohibited Prohibited

Potassium sulfide, anhydrous or

Potassium sulfide with less than

percent water of crystallization

4.2 UN1382 II Prohibited Prohibited

Potassium sulfide, hydrated with not

less than 30

percent water of

crystallization

8 UN1847 II Prohibited Prohibited

Potassium superoxide 5.1 UN2466 I Prohibited Prohibited

Powder cake, wetted or Powder

paste, wetted with not less than

25 percent water, by mass

1.3C UN0159 II Prohibited Prohibited

Powder cake, wetted or Powder

paste, wetted with not less than

17 percent alcohol by mass

1.1C UN0433 II Prohibited Prohibited

Powder paste, see Powder cake, etc.

Powder, smokeless 1.1C UN0160 II Prohibited Prohibited

Powder, smokeless 1.3C UN0161 II Prohibited Prohibited

Powder, smokeless 1.4C UN0509 n/a Prohibited Prohibited

Primers, cap type 1.1B UN0377 II Prohibited Prohibited

Primers, cap type 1.4B UN0378 II Prohibited Prohibited

Primers, cap type 1.4S UN0044 II Prohibited Prohibited

Primers, small arms, see Primers, cap

type

Primers, tubular 1.3G UN0319 II Prohibited Prohibited

Primers, tubular 1.4G UN0320 II Prohibited Prohibited

Primers, tubular 1.4S UN0376 II Prohibited Prohibited

Printing ink, flammable or Printing ink

related material (including printing

ink thinning or reducing compound),

flammable

3 UN1210 I, II, II Prohibited 3A

Projectiles, illuminating, see

Ammunition, illuminating, etc.

Projectiles, inert with tracer 1.3G UN0424 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 259

Projectiles, inert with tracer 1.4G UN0425 II Prohibited Prohibited

Projectiles, inert with tracer 1.4S UN0345 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.2D UN0346 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.2F UN0426 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.2G UN0434 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.4D UN0347 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.4F UN0427 II Prohibited Prohibited

Projectiles, with burster or expelling

charge

1.4G UN0435 II Prohibited Prohibited

Projectiles, with bursting charge 1.1D UN0168 II Prohibited Prohibited

Projectiles, with bursting charge 1.1F UN0167 II Prohibited Prohibited

Projectiles, with bursting charge 1.2D UN0169 II Prohibited Prohibited

Projectiles, with bursting charge 1.2F UN0324 II Prohibited Prohibited

Projectiles, with bursting charge 1.4D UN0344 II Prohibited Prohibited

Propadiene mixed with acetylene,

see Methyl acetylene and

propadiene mixtures, stabilized

Propadiene, stabilized 2.1 UN2200 n/a Prohibited Prohibited

Propane see also Petroleum gases,

liquified

2.1 UN1978 n/a Prohibited 2A

Propanethiols 3 UN2402 II Prohibited 3A

n-Propanol or Propyl alcohol, normal 3 UN1274 II, III Prohibited 3A

Propellant, liquid 1.1C UN0497 II Prohibited Prohibited

Propellant, liquid 1.3C UN0495 II Prohibited Prohibited

Propellant, solid 1.1C UN0498 II Prohibited Prohibited

Propellant, solid 1.3C UN0499 II Prohibited Prohibited

Propellant, solid 1.4C UN0501 n/a Prohibited Prohibited

Propionaldehyde 3 UN1275 II Prohibited 3A

Propionic acid with not less than

percent acid by mass

8 UN3463 II Prohibited 8A

Propionic acid with not less than

10 percent and less than 90 percent

acid by mass

8 UN1848 III 8A 8A

Propionic anhydride 8 UN2496 III 8A 8A

Propionitrile 3 UN2404 II Prohibited Prohibited

Propionyl chloride 3 UN1815 II Prohibited Prohibited

n-Propyl acetate 3 UN1276 II Prohibited 3A

Propyl alcohol, see Propanol

n-Propyl benzene 3 UN2364 III Prohibited 3A

Propyl chloride see 1-Chloropropane

n-Propyl chloroformate 6.1 UN2740 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

260 Publication 52

Propyl formates 3 UN1281 II Prohibited 3A

n-Propyl isocyanate 6.1 UN2482 I

Propyl mercaptan, see Propanethiols

n-Propyl nitrate 3 UN1865 II Prohibited 3A

Propylamine 3 UN1277 II Prohibited Prohibited

Propylene see also Petroleum gases,

liquified

2.1 UN1077 n/a Prohibited 2A

Propylene chlorohydrin 6.1 UN2611 II Prohibited Prohibited

Propylene oxide 3 UN1280 I Prohibited Prohibited

Propylene tetramer 3 UN2850 III Prohibited 3A

1,2-Propylenediamine 8 UN2258 II Prohibited Prohibited

Propyleneimine, stabilized 3 UN1921 I Prohibited Prohibited

Propyltrichlorosilane 8 UN1816 II Prohibited Prohibited

Prussic acid, see Hydrogen cyanide

etc.

Pyrethroid pesticide, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN3350 I, II Prohibited Prohibited

Pyrethroid pesticide, liquid,

flammable, toxic, flashpoint less

than 23° C

6.1 UN3351 I Prohibited Prohibited

Pyrethroid pesticide, liquid,

flammable, toxic, flashpoint less

than 23° C

6.1 UN3351 II, III 6A 6A

Pyrethroid pesticide, liquid, toxic 6.1 UN3352 I Prohibited Prohibited

Pyrethroid pesticide, liquid, toxic 6.1 UN3352 II, III 6A 6A

Pyrethroid pesticide, solid, toxic 6.1 UN3349 I Prohibited Prohibited

Pyrethroid pesticide, solid, toxic 6.1 UN3349 II, III 6A 6A

Pyridine 3 UN1282 II Prohibited Prohibited

Pyridine perchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Pyrophoric liquid, inorganic, n.o.s. 4.2 UN3194 I Prohibited Prohibited

Pyrophoric liquids, organic, n.o.s. 4.2 UN2845 I Prohibited Prohibited

Pyrophoric metals, n.o.s. or

Pyrophoric alloys, n.o.s.

4.2 UN1383 I Prohibited Prohibited

Pyrophoric solid, inorganic, n.o.s. 4.2 UN3200 I Prohibited Prohibited

Pyrophoric solids, organic, n.o.s. 4.2 UN2846 I Prohibited Prohibited

Pyrosulfuryl chloride 8 UN1817 II 8A 8A

Pyroxylin solution or solvent, see

Nitrocellulose

Pyrrolidine 3 UN1922 II Prohibited Prohibited

Quebrachitol pentanitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Quicklime, see Calcium oxide

Quinoline 6.1 UN2656 III 6A 6A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 261

R 12, see Dichlorodifluoromethane

R 12B1, see

Chlorodifluorobromomethane

R 13, see Chlorotrifluoromethane

R 13B1, see Bromotrifluoromethane

R 14, see Tetrafluoromethane

R 21, see Dichlorofluoromethane

R 22, see Chlorodifluoromethane

R 114, see Dichlorotetrafluroethane

R 115, see Chloropentafluoroethane

R 116, see Hexafluoroethane

R 124, see Chlorotetrafluoroethane

R 133a, see Chlorotrifluoroethane

R 152a, see Difluoroethane

R 500, see Dichlorodifluoromethane

and difluorethane, etc.

R 502, see Chlorodifluoromethane

and chloropentafluoroethane

mixture, etc.

R 503, see Chlorotrifluoromethane

and trifluoromethane, etc.

Radioactive material, excepted

package-articles manufactured

from natural uranium or depleted

uranium or natural thorium

7 UN2909 n/a Prohibited 7A

Radioactive material, excepted

package-empty packaging

7 UN2908 n/a Prohibited Prohibited

Radioactive material, excepted

package-instruments or articles

7 UN2911 n/a Prohibited 7A

Radioactive material, excepted

package-limited quantity of material

7 UN2910 n/a Prohibited 7A

Radioactive material, low specific

activity (LSA-I), non fissile or fissile-

excepted.

7 UN2912 n/a Prohibited Prohibited

Radioactive material, low specific

activity (LSA-II), non fissile or fissile-

excepted.

7 UN3321 n/a Prohibited Prohibited

Radioactive material, low specific

activity (LSA-III), non fissile or

fissile- excepted.

7 UN3322 n/a Prohibited Prohibited

Radioactive material, surface

contaminated objects (SCO-I or

SCO-II) non fissile or fissile-

excepted

7 UN2913 n/a Prohibited Prohibited

Radioactive material, transported

under special arrangement, non

fissile or fissile excepted

7 UN2919 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

262 Publication 52

Radioactive material, transported

under special arrangement, fissile

7 UN3331 n/a Prohibited Prohibited

Radioactive material, Type A

package, fissile non-special form

7 UN3327 n/a Prohibited Prohibited

Radioactive material, Type A

package, fissile non-special form,

non fissile or fissile-excepted

7 UN2915 n/a Prohibited Prohibited

Radioactive material, Type A

package, non fissile or fissile-

excepted

7 UN3332 n/a Prohibited Prohibited

Radioactive material, Type A

package, special form, fissile

7 UN3333 n/a Prohibited Prohibited

Radioactive material, Type B(M)

package, fissile

7 UN3329 n/a Prohibited Prohibited

Radioactive material, Type B(M)

package non fissile or fissile-

excepted

7 UN2917 n/a Prohibited Prohibited

Radioactive material, Type B(U)

package, fissile

7 UN3328 n/a Prohibited Prohibited

Radioactive material, Type B(U)

package non fissile or fissile-

excepted

7 UN2916 n/a Prohibited Prohibited

Radioactive material, uranium

hexafluoride nonfissile or fissile-

excepted

7 UN2978 n/a Prohibited Prohibited

Radioactive material, uranium

hexafluoride fissile

7 UN2977 n/a Prohibited Prohibited

Rags, oily 4.2 UN1856 III Prohibited Prohibited

Railway torpedo, see Signals, railway

track, explosive

RC318, see Octafluorocyclobutane

RDX and

cyclotetramethylenetetranitramine,

wetted or desensitized see RDX and

HMX mixtures, wetted or

desensitized

RDX and HMX mixtures, wetted with

not less than 15

percent water by

mass or RDX and HMX mixtures,

desensitized with not less than

percent phlegmatizer by mass

1.1D UN0391 II Prohibited Prohibited

RDX and Octogen mixtures, wetted

or desensitized see RDX and HMX

mixtures, wetted or desensitized,

etc.

RDX, see Cyclotrimethylene

trinitramine, etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 263

Receptacles, small, containing gas

(gas cartridges) flammable, without

release device, not refillable and not

exceeding 1 L capacity

2.1 UN2037 n/a Prohibited 2A

Receptacles, small, containing gas or

gas cartridges (nonflammable)

without release device, not refillable

and not exceeding 1 L capacity

2.2 UN2037 n/a 2B 2B

Receptacles, small, containing gas or

gas cartridges (oxidizing) without

release device, not refillable and not

exceeding 1 L capacity

2.2 UN2037 n/a Prohibited 2B

Red phosphorus, see Phosphorus,

amorphous

Refrigerant gas R 404A 2.2 UN3337 n/a 2B 2B

Refrigerant gas R 407A 2.2 UN3338 n/a 2B 2B

Refrigerant gas R 407B 2.2 UN3339 n/a 2B 2B

Refrigerant gas R 407C 2.2 UN3340 n/a 2B 2B

Refrigerant gases, n.o.s. 2.2 UN1078 n/a 2B 2B

Refrigerant gases, n.o.s., or

Dispersant gases, n.o.s.

2.1 NA1954 n/a Prohibited 2A

Refrigerating machines, containing

flammable, non-toxic, liquified gas

2.1 UN3358 n/a Prohibited 2A

Refrigerating machines, containing

non-flammable, non-toxic, or

ammonia solution (UN2672)

2.2 UN2857 n/a 2B 2B

Regulated medical waste (sharps),

n.o.s. or Clinical waste, unspecified,

n.o.s. or (BIO) Medical waste, n.o.s.

or Biomedical waste, n.o.s. or

Medical waste, n.o.s.

6.2 UN3291 II 6D n/a

Regulated medical waste

(nonsharps), n.o.s. or Clinical waste,

unspecified, n.o.s. or (BIO) Medical

waste, n.o.s. or Biomedical waste,

n.o.s. or Medical waste, n.o.s.

6.2 UN3291 II 6E n/a

Release devices, explosive 1.4S UN0173 II Prohibited Prohibited

Resin solution, flammable 3 UN1866 I, II, III Prohibited 3A

Resorcinol 6.1 UN2876 III 6A 6A

Rifle grenade, see Grenades, hand or

rifle, etc.

Rifle powder, see Powder, smokeless

(UN0160)

Rivets, explosive 1.4S UN0174 II Prohibited Prohibited

Road asphalt or tar liquid, see Tars,

liquid etc.

Rocket motors 1.3C UN0186 II Prohibited Prohibited

Rocket motors 1.1C UN0280 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

264 Publication 52

Rocket motors 1.2C UN0281 II Prohibited Prohibited

Rocket motors, liquid fueled 1.2J UN0395 II Prohibited Prohibited

Rocket motors, liquid fueled 1.3J UN0396 II Prohibited Prohibited

Rocket motors with hypergolic

liquids with or without an expelling

charge

1.3L UN0250 II Prohibited Prohibited

Rocket motors with hypergolic

liquids with or without an expelling

charge

1.2L UN0322 II Prohibited Prohibited

Rockets, line-throwing 1.2G UN0238 II Prohibited Prohibited

Rockets, line-throwing 1.3G UN0240 II Prohibited Prohibited

Rockets, line-throwing 1.4G UN0453 II Prohibited Prohibited

Rockets, liquid fueled with bursting

charge

1.1J UN0397 II Prohibited Prohibited

Rockets, liquid fueled with bursting

charge

1.2J UN0398 II Prohibited Prohibited

Rockets, with bursting charge 1.1E UN0181 II Prohibited Prohibited

Rockets, with bursting charge 1.1F UN0180 II Prohibited Prohibited

Rockets, with bursting charge 1.2E UN0182 II Prohibited Prohibited

Rockets, with bursting charge 1.2F UN0295 II Prohibited Prohibited

Rockets, with expelling charge 1.2C UN0436 II Prohibited Prohibited

Rockets, with expelling charge 1.3C UN0437 II Prohibited Prohibited

Rockets, with expelling charge 1.4C UN0438 II Prohibited Prohibited

Rockets, with inert head 1.3C UN0183 II Prohibited Prohibited

Rockets, with inert head 1.2C UN0502 n/a Prohibited Prohibited

Rosin oil 3 UN1286 II, III Prohibited 3A

Rubber solution 3 UN1287 II, III Prohibited 3A

Rubber scrap or shoddy, powdered

or granulated, not exceeding

840

microns and rubber contend

exceeding 45 percent

4.1 UN1345 II Prohibited Prohibited

Rubidium 4.3 UN1423 I Prohibited Prohibited

Rubidium hydroxide 8 UN2678 II 8A 8A

Rubidium hydroxide solution 8 UN2677 II, III 8A 8A

Safety fuse, see Fuse, safety

Samples, explosive, other than

initiating explosives

UN0190 II Prohibited Prohibited

Sand acid, see Fluorosilicic acid

Seed cake with more than

1.5

percent oil and not more than

11 percent moisture

4.2 UN1386 III Prohibited Prohibited

Seed cake with not more than

1.5 percent oil and not more than

11 percent moisture

4.2 UN2217 III Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 265

Seed cake, containing vegetable oil

solvent extractions and expelled

seeds, with not more than

percent of oil and when the

amount of moisture is higher than

percent, with not more than

20 percent of oil and moisture

combined

4.2 UN1386 III Prohibited Prohibited

Selenates or Selenites 6.1 UN2630 I Prohibited Prohibited

Selenic acid 8 UN1905 I Prohibited Prohibited

Selenium compound, liquid, n.o.s. 6.1 UN3440 I, II Prohibited Prohibited

Selenium compound, liquid, n.o.s. 6.1 UN3440 III 6A 6A

Selenium compound, solid, n.o.s. 6.1 UN3283 I, II Prohibited Prohibited

Selenium compound, solid, n.o.s. 6.1 UN3283 III 6A 6A

Selenium disulfide 6.1 UN2657 II Prohibited Prohibited

Selenium hexafluoride 2.3 UN2194 Prohibited Prohibited

Selenium nitride Forbidden Prohibited Prohibited Prohibited Prohibited

Selenium oxychloride 8 UN2879 I Prohibited Prohibited

Self-defense spray, aerosol, see

Aerosols, etc.

Self-defense spray, non-pressurized 9 NA3334 III 9C 9C

Self-heating liquid, corrosive,

inorganic, n.o.s.

4.2 UN3188 II, III Prohibited Prohibited

Self-heating liquid, corrosive,

organic, n.o.s.

4.2 UN3185 II, III Prohibited Prohibited

Self-heating liquid, inorganic, n.o.s. 4.2 UN3186 II, III Prohibited Prohibited

Self-heating liquid, organic, n.o.s. 4.2 UN3183 II, III Prohibited Prohibited

Self-heating liquid, toxic, inorganic,

n.o.s.

4.2 UN3187 II, III Prohibited Prohibited

Self-heating liquid, toxic, organic,

n.o.s.

4.2 UN3184 II, III Prohibited Prohibited

Self-heating solid, corrosive,

inorganic, n.o.s.

4.2 UN3192 II, III Prohibited Prohibited

Self-heating solid, corrosive, organic,

n.o.s.

4.2 UN3126 II, III Prohibited Prohibited

Self-heating solid, inorganic, n.o.s. 4.2 UN3190 II, III Prohibited Prohibited

Self-heating solid, organic, n.o.s. 4.2 UN3088 II, III Prohibited Prohibited

Self-heating solid, oxidizing, n.o.s. 4.2 UN3127 n/a Prohibited Prohibited

Self-heating solid, toxic, inorganic,

n.o.s.

4.2 UN3191 II, III Prohibited Prohibited

Self-heating solid, toxic, organic,

n.o.s.

4.2 UN3128 II, III Prohibited Prohibited

Self-propelled vehicle, see Engines

etc. or Batteries etc.

Self-reactive liquid type B 4.1 UN3221 II Prohibited Prohibited

Self-reactive liquid type B,

temperature controlled

4.1 UN3231 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

266 Publication 52

Self-reactive liquid type C 4.1 UN3223 II Prohibited Prohibited

Self-reactive liquid type C,

temperature controlled

4.1 UN3233 II Prohibited Prohibited

Self-reactive liquid type D 4.1 UN3225 II Prohibited Prohibited

Self-reactive liquid type D,

temperature controlled

4.1 UN3235 II Prohibited Prohibited

Self-reactive liquid type E 4.1 UN3227 II Prohibited Prohibited

Self-reactive liquid type E,

temperature controlled

4.1 UN3237 II Prohibited Prohibited

Self-reactive liquid type F 4.1 UN3229 II Prohibited Prohibited

Self-reactive liquid type F,

temperature controlled

4.1 UN3239 II Prohibited Prohibited

Self-reactive solid type B 4.1 UN3222 II Prohibited Prohibited

Self-reactive solid type B,

temperature controlled

4.1 UN3232 II Prohibited Prohibited

Self-reactive solid type C 4.1 UN3224 II Prohibited Prohibited

Self-reactive solid type C,

temperature controlled

4.1 UN3234 II Prohibited Prohibited

Self-reactive solid type D 4.1 UN3226 II Prohibited Prohibited

Self-reactive solid type D,

temperature controlled

4.1 UN3236 II Prohibited Prohibited

Self-reactive solid type E 4.1 UN3228 II Prohibited Prohibited

Self-reactive solid type E,

temperature controlled

4.1 UN3238 II Prohibited Prohibited

Self-reactive solid type F 4.1 UN3230 II Prohibited Prohibited

Self-reactive solid type F,

temperature controlled

4.1 UN3240 II Prohibited Prohibited

Shale Oil 3 UN1288 I Prohibited Prohibited

Shale Oil 3 UN1288 II, III Prohibited 3A

Shaped charges, see Charges,

shaped, etc.

Signal devices, hand 1.4G UN0191 II Prohibited Prohibited

Signal devices, hand 1.4S UN0373 II Prohibited Prohibited

Signals, distress, ship 1.1G UN0194 II Prohibited Prohibited

Signals, distress, ship 1.3G UN0195 II Prohibited Prohibited

Signals, distress, ship 1.4G UN0505 n/a Prohibited Prohibited

Signals, distress, ship 1.4S UN0506 n/a Prohibited Prohibited

Signals, highway, see Signal devices,

hand

Signals, railway track, explosive 1.1G UN0192 II Prohibited Prohibited

Signals, railway track, explosive 1.3G UN0492 II Prohibited Prohibited

Signals, railway track, explosive 1.4G UN0493 II Prohibited Prohibited

Signals, railway track, explosive 1.4S UN0193 II Prohibited Prohibited

Signals, ship distress, water-

activated, see Contrivances, water-

activated, etc.

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 267

Signals, smoke 1.1G UN0196 II Prohibited Prohibited

Signals, smoke 1.2G UN0313 II Prohibited Prohibited

Signals, smoke 1.3G UN0487 II Prohibited Prohibited

Signals, smoke 1.4G UN0197 II Prohibited Prohibited

Signals, smoke 1.4S UN0507 n/a Prohibited Prohibited

Silane 2.1 UN2203 n/a Prohibited Prohibited

Silicofluoric acid, see Fluorosilicic

acid

Silicon chloride, see Silicon

tetrachloride

Silicon powder, amorphous 4.1 UN1346 III Prohibited Prohibited

Silicon tetrachloride 8 UN1818 II 8A 8A

Silicon tetrafluoride, compressed 2.3 UN1859 n/a Prohibited Prohibited

Silver acetylide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Silver arsenite 6.1 UN1683 II Prohibited Prohibited

Silver azide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Silver chlorite (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Silver cyanide 6.1 UN1684 II Prohibited Prohibited

Silver fulminate (dry) Forbidden Prohibited Prohibited

Silver nitrate 5.1 UN1493 II 5A 5A

Silver oxalate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Silver picrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Silver picrate, wetted with not less

than 30 percent water, by mass

4.1 UN1347 I Prohibited Prohibited

Sludge, acid 8 UN1906 II Prohibited Prohibited

Smokeless powder for small arms

(100 pounds or less)

4.1 NA3178 I Prohibited Prohibited

Soda lime with more than 4 percent

sodium hydroxide

8 UN1907 III 8A 8A

Sodium 4.3 UN1428 I Prohibited Prohibited

Sodium aluminate, solid 8 UN2812 III 8A 8A

Sodium aluminate, solution 8 UN1819 II, III 8A 8A

Sodium aluminum hydride 4.3 UN2835 II Prohibited 4A

Sodium ammonium vanadate 6.1 UN2863 II Prohibited Prohibited

Sodium arsanilate 6.1 UN2473 III 6A 6A

Sodium arsenate 6.1 UN1685 II Prohibited Prohibited

Sodium arsenite, aqueous solutions 6.1 UN1686 II Prohibited Prohibited

Sodium arsenite, aqueous solutions 6.1 UN1686 III 6A 6A

Sodium arsenite, solid 6.1 UN2027 II Prohibited Prohibited

Sodium azide 6.1 UN1687 II Prohibited Prohibited

Sodium bifluoride, see Sodium

hydrogendifluoride

Sodium bisulfite, solution, see

Bisulfites, aqueous solutions, n.o.s.

Sodium borohydride 4.3 UN1426 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

268 Publication 52

Sodium borohydride and sodium

hydroxide solution, with not more

than 12

percent sodium

borohydride and not more than

percent sodium hydroxide by

mass

8 UN3320 II, III Prohibited Prohibited

Sodium bromate 5.1 UN1494 II 5A 5A

Sodium cacodylate 6.1 UN1688 II Prohibited Prohibited

Sodium carbonate peroxyhydrate 5.1 UN3378 II, III 5A 5A

Sodium chlorate 5.1 UN1495 II 5A 5A

Sodium chlorate, aqueous solution 5.1 UN2428 II, III 5A 5A

Sodium chlorate mixed with

dinitrotoluene, see Explosive,

blasting, type C

Sodium chlorite 5.1 UN1496 II Prohibited Prohibited

Sodium chloroacetate 6.1 UN2659 III 6A 6A

Sodium cuprocyanide, solid 6.1 UN2316 I Prohibited Prohibited

Sodium cuprocyanide, solution 6.1 UN2317 I Prohibited Prohibited

Sodium cyanide, solid 6.1 UN1689 I Prohibited Prohibited

Sodium cyanide, solution 6.1 UN3414 I, II Prohibited Prohibited

Sodium cyanide, solution 6.1 UN3414 III Prohibited 6A

Sodium dichloroisocyanurate or

Sodium dichloro-s-triazinetrione,

see Dichloroisocyanuric acid etc.

Sodium dinitro-o-cresolate, dry or

wetted with less than 15

percent

water, by mass

1.3C UN0234 II Prohibited Prohibited

Sodium dinitro-o-cresolate, wetted

with not less than 10

percent water,

by mass

4.1 UN3369 I Prohibited Prohibited

Sodium dinitro-o-cresolate, wetted

with not less than 15

percent water,

by mass

4.1 UN1348 I Prohibited Prohibited

Sodium dithionite or Sodium

hydrosulfite

4.2 UN1384 II Prohibited Prohibited

Sodium fluoride, solid 6.1 UN1690 III 6A 6A

Sodium fluoride, solution 6.1 UN3415 III 6A 6A

Sodium fluoroacetate 6.1 UN2629 I Prohibited Prohibited

Sodium fluorosilicate 6.1 UN2674 III 6A 6A

Sodium hydrate, see Sodium

hydroxide, solid

Sodium hydride 4.3 UN1427 I Prohibited Prohibited

Sodium hydrogendifluoride 8 UN2439 II 8A 8A

Sodium hydrosulfide, with less than

25 percent water of crystallization

4.2 UN2318 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 269

Sodium hydrosulfide, with not less

than 25 percent water of

crystallization

8 UN2949 II Prohibited Prohibited

Sodium hydrosulfite, see Sodium

dithionite

Sodium hydroxide, solid 8 UN1823 II 8A 8A

Sodium hydroxide solution 8 UN1824 II, III 8A 8A

Sodium hypochlorite, solution, see

Hypochlorite solutions

Sodium metal, liquid alloy, see Alkali

metal alloys, liquid, n.o.s.

Sodium methylate 4.2 UN1431 II Prohibited Prohibited

Sodium methylate solutions in

alcohol

3 UN1289 II Prohibited Prohibited

Sodium methylate solutions in

alcohol

3 UN1289 III Prohibited 3A

Sodium monoxide 8 UN1825 II 8A 8A

Sodium nitrate 5.1 UN1498 III 5A 5A

Sodium nitrate and potassium nitrate

mixtures

5.1 UN1499 III 5A 5A

Sodium nitrite 5.1 UN1500 III 5A 5A

Sodium pentachlorophenate 6.1 UN2567 II Prohibited Prohibited

Sodium perborate monohydrate 5.1 UN3377 III 5A 5A

Sodium perchlorate 5.1 UN1502 II 5A 5A

Sodium permanganate 5.1 UN1503 II 5A 5A

Sodium peroxide 5.1 UN1504 I Prohibited Prohibited

Sodium peroxoborate, anhydrous 5.1 UN3247 II 5A 5A

Sodium persulfate 5.1 UN1505 III 5A 5A

Sodium phosphide 4.3 UN1432 I Prohibited 4A

Sodium picramate, dry or wetted with

less than 20 percent water, by mass

1.3C UN0235 II Prohibited Prohibited

Sodium picramate, wetted with not

less than 20 percent water, by mass

4.1 UN1349 I Prohibited Prohibited

Sodium picryl peroxide Forbidden Prohibited Prohibited Prohibited Prohibited

Sodium potassium alloys, see

Potassium sodium alloys

Sodium selenate, see Selenates or

Selenites

Sodium sulfide, anhydrous or

Sodium sulfide with less than

percent water of crystallization

4.2 UN1385 II Prohibited Prohibited

Sodium sulfide, hydrated with not

less than 30

percent water

8 UN1849 II Prohibited Prohibited

Sodium superoxide 5.1 UN2547 I Prohibited Prohibited

Sodium tetranitride Forbidden Prohibited Prohibited Prohibited Prohibited

Solids containing corrosive liquid,

n.o.s.

8 UN3244 II 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

270 Publication 52

Solids containing flammable liquid,

n.o.s.

4.1 UN3175 II Prohibited 4A

Solids containing toxic liquid, n.o.s. 6.1 UN3243 II Prohibited Prohibited

Sounding devices, explosive 1.1D UN0374 II Prohibited Prohibited

Sounding devices, explosive 1.1F UN0296 II Prohibited Prohibited

Sounding devices, explosive 1.2D UN0375 II Prohibited Prohibited

Sounding devices, explosive 1.2F UN0204 II Prohibited Prohibited

Spirits of salt, see Hydrochloric acid

Squibs, see Igniters

Stannic chloride, anhydrous 8 UN1827 II 8A 8A

Stannic chloride, pentahydrate 8 UN2440 III 8A 8A

Stannic phosphide 4.3 UN1433 I Prohibited Prohibited

Steel swarf, see Ferrous metal

borings, etc.

Stibine 2.3 UN2676 n/a Prohibited Prohibited

Storage batteries, wet, see Batteries,

wet etc.

Strontium arsenite 6.1 UN1691 II Prohibited Prohibited

Strontium chlorate 5.1 UN1506 II 5A 5A

Strontium nitrate 5.1 UN1507 III 5A 5A

Strontium perchlorate 5.1 UN1508 II 5A 5A

Strontium peroxide 5.1 UN1509 II 5A 5A

Strontium phosphide 4.3 UN2013 I Prohibited Prohibited

Strychnine or Strychnine salts 6.1 UN1692 I Prohibited Prohibited

Stryphnic acid, see Trinitroresorcinol,

etc.

Styrene monomer, stabilized 3 UN2055 III Prohibited 3A

Substances, explosive, n.o.s. 1.1A UN0473 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.1C UN0474 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.1D UN0475 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.1G UN0476 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.1L UN0357 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.2L UN0358 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.3C UN0477 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.3G UN0478 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.3L UN0359 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.4C UN0479 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.4D UN0480 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.4G UN0485 II Prohibited Prohibited

Substances, explosive, n.o.s. 1.4S UN0481 II Prohibited Prohibited

Substances, explosive, very

insensitive, n.o.s., or Substances,

EVI, n.o.s.

1.5D UN0482 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 271

Substituted nitrophenol pesticides,

liquid, flammable, toxic, flashpoint

less than 23° C

3 UN2780 I, II Prohibited Prohibited

Substituted nitrophenol pesticides,

liquid, toxic

6.1 UN3014 I, II Prohibited Prohibited

Substituted nitrophenol pesticides,

liquid, toxic

6.1 UN3014 III 6A 6A

Substituted nitrophenol pesticides,

liquid, toxic flammable flashpoint

not less than 23° C

6.1 UN3013 I, II Prohibited Prohibited

Substituted nitrophenol pesticides,

liquid, toxic flammable flashpoint

not less than 23° C

6.1 UN3013 III 6A 6A

Substituted nitrophenol pesticides,

solid, toxic

6.1 UN2779 I, II Prohibited Prohibited

Substituted nitrophenol pesticides,

solid, toxic

6.1 UN2779 III 6A 6A

Sucrose octanitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Sulfamic acid 8 UN2967 III 8A 8A

Sulfur 9 NA1350 III Prohibited Prohibited

Sulfur 4.1 UN1350 III Prohibited Prohibited

Sulfur and chlorate, loose mixtures of Forbidden Prohibited Prohibited Prohibited Prohibited

Sulfur chlorides 8 UN1828 I Prohibited Prohibited

Sulfur dichloride, see Sulfur chlorides

Sulfur dioxide 2.3 UN1079 n/a Prohibited Prohibited

Sulfur dioxide solution, see Sulfurous

acid

Sulfur hexafluoride 2.2 UN1080 n/a 2B 2B

Sulfur, molten 9 NA2448 III Prohibited Prohibited

Sulfur, molten 4.1 UN2448 III Prohibited Prohibited

Sulfur tetrafluoride 2.3 UN2418 n/a Prohibited Prohibited

Sulfur trioxide, stabilized 8 UN1829 I Prohibited Prohibited

Sulfuretted hydrogen, see Hydrogen

sulfide

Sulfuric acid with more than

51 percent acid

8 UN1830 II Prohibited Prohibited

Sulfuric acid with not more than

percent acid

8 UN2796 II 8A 8A

Sulfuric acid, fuming with 30 percent

or more free sulfur trioxide

8 UN1831 I Prohibited Prohibited

Sulfuric acid, fuming with less than

30 percent free sulfur trioxide

8 UN1831 I Prohibited Prohibited

Sulfuric acid, spent 8 UN1832 II Prohibited Prohibited

Sulfuric and hydrofluoric acid

mixtures, see Hydrofluoric and

sulfuric acid mixtures

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

272 Publication 52

Sulfuric anhydride, see Sulfur

trioxide, inhibited

Sulfurous acid 8 UN1833 II 8A 8A

Sulfuryl chloride 8 UN1834 I Prohibited Prohibited

Sulfuryl fluoride 2.3 UN2191 n/a Prohibited Prohibited

Tars, liquid including road oils and

cutback, bitumens

3 UN1999 II, III Prohibited 3A

Tear gas candles 6.1 UN1700 II Prohibited Prohibited

Tear gas cartridges, see Ammunition,

tearproducing, etc.

Tear gas devices with more than

2 percent tear gas substances, by

mass

6.1 NA1693 I, II Prohibited Prohibited

Tear gas devices with not more than

2 percent tear gas substances, by

mass, see Aerosols, etc.

Tear gas grenades, see Tear gas

candles

Tear gas substances, liquid, n.o.s. 6.1 UN1693 I, II Prohibited Prohibited

Tear gas substances, solid, n.o.s. 6.1 UN3448 I, II Prohibited Prohibited

Tellurium compound, n.o.s. 6.1 UN3284 I, II Prohibited Prohibited

Tellurium compound, n.o.s. 6.1 UN3284 III 6A 6A

Tellurium hexafluoride 2.3 UN2195 n/a Prohibited Prohibited

Terpene hydrocarbons, n.o.s. 3 UN2319 III Prohibited 3A

Terpinolene 3 UN2541 III Prohibited 3A

Tetraazido benzene quinone Forbidden Prohibited Prohibited Prohibited Prohibited

Tetrabromoethane 6.1 UN2504 III 6A 6A

1,1,2,2-Tetrachloroethane 6.1 UN1702 II Prohibited Prohibited

Tetrachloroethylene 6.1 UN1897 III 6A 6A

Tetraethyl dithiopyrophosphate 6.1 UN1704 II Prohibited Prohibited

Tetraethyl silicate 3 UN1292 III Prohibited 3A

Tetraethylammonium perchlorate

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Tetraethylenepentamine 8 UN2320 III 8A 8A

1,1,1,2-Tetrafluoroethane or

Refrigerant gas R 134a

2.2 UN3159 n/a 2B 2B

Tetrafluoroethylene, stabilized 2.1 UN1081 n/a Prohibited 2A

Tetrafluoromethane or Refrigerant

gas R 14

2.2 UN1982 n/a Prohibited Prohibited

1,2,3,6-Tetrahydrobenzaldehyde 3 UN2498 III Prohibited 3A

Tetrahydrofuran 3 UN2056 II Prohibited Prohibited

Tetrahydrofurfurylamine 3 UN2943 III Prohibited 3A

Tetrahydrophthalic anhydrides with

more than 0.05 percent of maleic

anhydride

8 UN2698 III 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 273

1,2,3,6-Tetrahydropyridine 3 UN2410 II Prohibited 3A

Tetrahydrothiophene 3 UN2412 II Prohibited 3A

Tetramethylammonium hydroxide,

solid

8 UN3423 II 8A 8A

Tetramethylammonium hydroxide,

solution

8 UN1835 II 8A 8A

Tetramethylene diperoxide

dicarbamide

Forbidden Prohibited Prohibited Prohibited Prohibited

Tetramethylsilane 3 UN2749 I Prohibited Prohibited

Tetranitro diglycerin Forbidden Prohibited Prohibited Prohibited Prohibited

Tetranitroaniline 1.1D UN0207 II Prohibited Prohibited

Tetranitromethane 5.1 UN1510 I Prohibited Prohibited

2,3,4,6-Tetranitrophenol Forbidden Prohibited Prohibited Prohibited Prohibited

2,3,4,6-Tetranitrophenyl methyl

nitramine

Forbidden Prohibited Prohibited Prohibited Prohibited

2,3,4,6-Tetranitrophenylnitramine Forbidden Prohibited Prohibited Prohibited Prohibited

Tetranitroresorcinol (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

2,3,5,6-Tetranitroso nitrobenzene

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

2,3,5,6-Tetranitroso-1,4-

dinitrobenzene

Forbidden Prohibited Prohibited Prohibited Prohibited

Tetrapropylorthotitanate 3 UN2413 III Prohibited 3A

Tetrazene, see Guanyl

nitrosaminoguanyltetrazene

Tetrazine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Tetrazol-1-acetic acid 1.4C UN0407 II Prohibited Prohibited

1H-Tetrazole 1.1D UN0504 n/a Prohibited Prohibited

Tetrazolyl azide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Tetryl, see

Trinitrophenylmethylnitramine

Textile waste, wet 4.2 UN1857 III Prohibited Prohibited

Thallium chlorate 5.1 UN2573 II Prohibited Prohibited

Thallium compounds, n.o.s. 6.1 UN1707 II Prohibited Prohibited

Thallium nitrate 6.1 UN2727 II Prohibited Prohibited

4-Thiapentanal 6.1 UN2785 III 6A 6A

Thioacetic acid 3 UN2436 II Prohibited 3A

Thiocarbamate pesticide, liquid,

flammable, toxic, flashpoint less

than 23° C

3 UN2772 I, II Prohibited Prohibited

Thiocarbamate pesticide, liquid,

toxic

6.1 UN3006 I, II Prohibited Prohibited

Thiocarbamate pesticide, liquid,

toxic

6.1 UN3006 III 6A 6A

Thiocarbamate pesticides, liquid,

flammable, toxic, flashpoint not less

than 23°C

6.1 UN3005 I, II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

274 Publication 52

Thiocarbamate pesticides, liquid,

flammable, toxic, flashpoint not less

than 23° C

6.1 UN3005 III 6A 6A

Thiocarbamate pesticides, solid,

toxic

6.1 UN2771 I, II Prohibited Prohibited

Thiocarbamate pesticides, solid,

toxic

6.1 UN2771 III 6A 6A

Thiocarbonylchloride, see

Thiophosgene

Thiogylcol 6.1 UN2966 II Prohibited Prohibited

Thioglycolic acid 8 UN1940 II 8A 8A

Thiolactic acid 6.1 UN2936 II Prohibited Prohibited

Thionyl chloride 8 UN1836 I Prohibited Prohibited

Thiophene 3 UN2414 II Prohibited 3A

Thiophosgene 6.1 UN2474 II Prohibited Prohibited

Thiophosphoryl chloride 8 UN1837 II Prohibited Prohibited

Thiourea dioxide 4.2 UN3341 II, III Prohibited Prohibited

Tin chloride, fuming, see Stannic

chloride, anhydrous

Tin perchloride or Tin tetrachloride,

see Stannic chloride, anhydrous

Tinctures, medicinal 3 UN1293 II, III Prohibited 3A

Tinning flux, see Zinc chloride

Tires and tire assemblies, see Air

compressed or Nitrogen,

compressed

Titanium disulphide 4.2 UN3174 III Prohibited Prohibited

Titanium hydride 4.1 UN1871 II Prohibited Prohibited

Titanium powder, dry 4.2 UN2546 I, II, III Prohibited Prohibited

Titanium powder, wetted with not

less than 25 percent water (a visible

excess of water must be present) (a)

mechanically produced, particle size

less than 53 microns; (b) chemically

produced, particle size less than

840 microns

4.1 UN1352 II Prohibited Prohibited

Titanium sponge granules or

Titanium sponge powders

4.1 UN2878 III Prohibited Prohibited

Titanium tetrachloride 8 UN1838 II Prohibited Prohibited

Titanium trichloride mixtures 8 UN2869 II, III 8A 8A

Titanium trichloride, pryophoric or

Titanium trichloride mixtures,

pyrophoric

4.2 UN2441 I Prohibited Prohibited

TNT mixed with aluminum, see

Tritonal

TNT, see Trinitrotoluene, etc.

Toluene 3 UN1294 II Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 275

Toluene diisocyanate 6.1 UN2078 II Prohibited Prohibited

Toluene sulfonic acid, see Alkyl, or

Aryl sulfonic acid, etc.

Toluidines liquid 6.1 UN1708 II Prohibited Prohibited

Toluidines solid 6.1 UN3451 II Prohibited Prohibited

2,4-Toluylenediamine, solid or 2,4-

Toluenediamine, solid

6.1 UN1709 III 6A 6A

2,4-Toluylenediamine, solution or

2,4-Toluenediamine, solution

6.1 UN3418 III 6A 6A

Torpedoes with bursting charge 1.1D UN0451 II Prohibited Prohibited

Torpedoes with bursting charge 1.1E UN0329 II Prohibited Prohibited

Torpedoes with bursting charge 1.1F UN0330 II Prohibited Prohibited

Torpedoes, liquid fueled, with inert

head

1.3J UN0450 II Prohibited Prohibited

Torpedoes, liquid fueled, with or

without bursting charge

1.1J UN0449 II Prohibited Prohibited

Toxic by inhalation liquid, flammable,

corrosive, n.o.s. with an LC50 lower

than or equal to 200 ml/ m3 and

saturated vapor concentration

greater than or equal to 500 LC50

6.1 UN3488 I Prohibited Prohibited

Toxic by inhalation liquid, flammable,

corrosive, n.o.s. with an LC50 lower

than or equal to 1000 ml/ m3 and

saturated vapor concentration

greater than or equal to 10 LC50

6.1 UN3489 I Prohibited Prohibited

Toxic by inhalation liquid, n.o.s. with

an LC50 lower than or equal to

200

ml/m3 and saturated vapor

concentration greater than or equal

to 500 LC50

6.1 UN3381 I Prohibited Prohibited

Toxic by inhalation liquid, n.o.s. with

an LC50 lower than or equal to

1000 ml/m3 and saturated vapor

concentration greater than or equal

to 10 LC50

6.1 UN3382 I Prohibited Prohibited

Toxic by inhalation liquid, flammable,

n.o.s. with an LC50 lower than or

equal to 200 ml/m3 and saturated

vapor concentration greater than or

equal to 500 LC50

6.1 UN3383 I Prohibited Prohibited

Toxic by inhalation liquid, flammable,

n.o.s. with an LC50 lower than or

equal to 1000 ml/m3 and saturated

vapor concentration greater than or

equal to 10 LC50

6.1 UN3384 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

276 Publication 52

Toxic by inhalation liquid, water-

reactive, flammable, n.o.s. with an

LC50 lower than or equal to 200 ml/

m3 and saturated vapor

concentration greater than or equal

to 500 LC50-

6.1 UN3490 I Prohibited Prohibited

Toxic by inhalation liquid, water-

reactive, flammable, n.o.s. with an

LC50 lower than or equal to 1000

ml/ m3 and saturated vapor

concentration greater than or equal

to 10 LC50-

6.1 UN3491 I Prohibited Prohibited

Toxic by inhalation liquid, water-

reactive, n.o.s. with an LC50 lower

than or equal to 200 ml/m3 and

saturated vapor concentration

greater than or equal to 500 LC50

6.1 UN3385 I Prohibited Prohibited

Toxic by inhalation liquid, water-

reactive, n.o.s. with an LC50 lower

than or equal to 1000 ml/m3 and

saturated vapor concentration

greater than or equal to 10 LC50

6.1 UN3386 I Prohibited Prohibited

Toxic by inhalation liquid, oxidizing,

n.o.s. with an LC50 lower than or

equal to 200 ml/m3 and saturated

vapor concentration greater than or

equal to 500 LC50

6.1 UN3387 I Prohibited Prohibited

Toxic by inhalation liquid, oxidizing,

n.o.s. with an LC50 lower than or

equal to 1000 ml/m3 and saturated

vapor concentration greater than or

equal to 10 LC50

6.1 UN3388 I Prohibited Prohibited

Toxic by inhalation liquid, corrosive,

n.o.s. with an LC50 lower than or

equal to 200 ml/m3 and saturated

vapor concentration greater than or

equal to 500 LC50

6.1 UN3389 I Prohibited Prohibited

Toxic by inhalation liquid, corrosive,

n.o.s. with an LC50 lower than or

equal to 1000 ml/m3 and saturated

vapor concentration greater than or

equal to 10 LC50

6.1 UN3390 I Prohibited Prohibited

Toxic liquid, corrosive, inorganic,

n.o.s.

6.1 UN3289 I, II Prohibited Prohibited

Toxic liquid, inorganic, n.o.s. 6.1 UN3287 I, II Prohibited Prohibited

Toxic liquid, inorganic, n.o.s. 6.1 UN3287 III 6A 6A

Toxic liquids, corrosive, organic,

n.o.s.

6.1 UN2927 I, II Prohibited Prohibited

Toxic liquids, flammable, organic,

n.o.s.

6.1 UN2929 I, II Prohibited Prohibited

Toxic, liquids, organic, n.o.s. 6.1 UN2810 I, II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 277

Toxic, liquids, organic, n.o.s. 6.1 UN2810 III 6A 6A

Toxic liquids, oxidizing, n.o.s. 6.1 UN3122 I, II Prohibited Prohibited

Toxic liquids, water-reactive, n.o.s. 6.1 UN3123 I, II Prohibited Prohibited

Toxic solid, corrosive, inorganic,

n.o.s.

6.1 UN3290 I, II Prohibited Prohibited

Toxic solid, inorganic, n.o.s. 6.1 UN3288 I, II Prohibited Prohibited

Toxic solid, inorganic, n.o.s. 6.1 UN3288 III 6A 6A

Toxic solids, corrosive, organic,

n.o.s.

6.1 UN2928 I, II Prohibited Prohibited

Toxic solids, flammable, organic,

n.o.s.

6.1 UN2930 I, II Prohibited Prohibited

Toxic solids, organic, n.o.s. 6.1 UN2811 I, II Prohibited Prohibited

Toxic solids, organic, n.o.s 6.1 UN2811 III 6A 6A

Toxic solids, oxidizing, n.o.s. 6.1 UN3086 I, II Prohibited Prohibited

Toxic solids, self-heating, n.o.s. 6.1 UN3124 I, II Prohibited Prohibited

Toxic solids, water-reactive, n.o.s. 6.1 UN3125 I, II Prohibited Prohibited

Toxins, extracted from living sources,

liquid, n.o.s.

6.1 UN3172 I, II Prohibited Prohibited

Toxins, extracted from living sources,

liquid, n.o.s.

6.1 UN3172 III 6A 6A

Toxins, extracted from living sources,

solid, n.o.s.

6.1 UN3462 I, II Prohibited Prohibited

Toxins, extracted from living sources,

solid, n.o.s.

6.1 UN3462 III 6A 6A

Toy caps 1.4S NA0337 II Prohibited Prohibited

Tracers for ammunition 1.3G UN0212 II Prohibited Prohibited

Tracers for ammunition 1.4G UN0306 II Prohibited Prohibited

Tractors, see Vehicle, etc.

Tri-(b-nitroxyethyl) ammonium nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Triallyl borate 6.1 UN2609 III 6A 6A

Triallylamine 3 UN2610 III Prohibited Prohibited

Triazine pesticides, liquid, flammable,

toxic, flashpoint less than 23° C

3 UN2764 I, II Prohibited Prohibited

Triazine pesticides, liquid, toxic 6.1 UN2998 I, II Prohibited Prohibited

Triazine pesticides, liquid, toxic 6.1 UN2998 III 6A 6A

Triazine pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN2997 I, II Prohibited Prohibited

Triazine pesticides, liquid, toxic,

flammable, flashpoint not less than

23° C

6.1 UN2997 III 6A 6A

Triazine pesticides, solid, toxic 6.1 UN2763 I, II Prohibited Prohibited

Triazine pesticides, solid, toxic 6.1 UN2763 III 6A 6A

Tributylamine 6.1 UN2542 II Prohibited Prohibited

Tributylphosphane 4.2 UN3254 I Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

278 Publication 52

Trichloro-s-triazinetrione dry, with

more than 39 percent available

chlorine, see Trichloroisocyanuric

acid, dry

Trichloroacetic acid 8 UN1839 II 8A 8A

Trichloroacetic acid, solution 8 UN2564 II, III 8A 8A

Trichloroacetyl chloride 8 UN2442 II Prohibited Prohibited

Trichlorbenzenes, liquid 6.1 UN2321 III 6A 6A

Trichlorobutene 6.1 UN2322 II Prohibited Prohibited

1,1,1-Trichloroethane 6.1 UN2831 III 6A 6A

Trichloroethylene 6.1 UN1710 III 6A 6A

Trichloroisocyanuric acid, dry 5.1 UN2468 II 5A 5A

Trichloromethyl perchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Trichlorosilane 4.3 UN1295 I Prohibited Prohibited

Tricresyl phosphate with more than

3 percent ortho isomer

6.1 UN2574 II Prohibited Prohibited

Triethyl phosphite 3 UN2323 III Prohibited 3A

Triethylamine 3 UN1296 II Prohibited Prohibited

Triethylenetetramine 8 UN2259 II 8A 8A

Trifluoroacetic acid 8 UN2699 I Prohibited Prohibited

Trifluoroacetyl chloride 2.3 UN3057 n/a Prohibited Prohibited

Trifluorochloroethylene, stabilized 2.3 UN1082 n/a Prohibited Prohibited

1,1,1-Trifluoroethane, compressed

or Refrigerant gas R 143a

2.1 UN2035 n/a Prohibited 2A

Trifluoromethane or Refrigerant gas

R 23

2.2 UN1984 n/a 2B 2B

Trifluoromethane, refrigerated liquid 2.2 UN3136 n/a 2B 2B

2-Trifluoromethylaniline 6.1 UN2942 III 6A 6A

3-Trifluoromethylaniline 6.1 UN2948 II Prohibited Prohibited

Triformoxime trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Triisobutylene 3 UN2324 III Prohibited 3A

Triisopropyl borate 3 UN2616 II, III Prohibited 3A

Trimethoxysilane 6.1 NA9269 I Prohibited Prohibited

Trimethyl borate 3 UN2416 II Prohibited 3A

Trimethyl phosphite 3 UN2329 III Prohibited 3A

1,3,5-Trimethyl-2,4,6-trinitrobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

Trimethylacetyl chloride 6.1 UN2438 I Prohibited Prohibited

Trimethylamine, anhydrous 2.1 UN1083 n/a Prohibited 2A

Trimethylamine, aqueous solutions

with not more than 50

percent

trimethylamine by mass

3 UN1297 I, II Prohibited Prohibited

Trimethylamine, aqueous solutions

with not more than 50

percent

trimethylamine by mass

3 UN1297 III Prohibited 3A

1,3,5-Trimethylbenzene 3 UN2325 III Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 279

Trimethylchlorosilane 3 UN1298 II Prohibited Prohibited

Trimethylcyclohexylamine 8 UN2326 III 8A 8A

Trimethylene glycol diperchlorate Forbidden Prohibited Prohibited Prohibited Prohibited

Trimethylhexamethylene

diisocyanate

6.1 UN2328 III 6A 6A

Trimethylhexamethylenediamines 8 UN2327 III 8A 8A

Trimethylol nitromethane trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitro-m-cresol 1.1D UN0216 II Prohibited Prohibited

2,4,6-Trinitro-1,3,5-triazido benzene

(dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

2,4,6-Trinitro-1,3-diazobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitroacetic acid Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitroacetonitrile Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitroamine cobalt Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitroaniline or Picramide 1.1D UN0153 II Prohibited Prohibited

Trinitroanisole 1.1D UN0213 II Prohibited Prohibited

Trinitrobenzene, wetted, with not less

than 10 percent water, by mass

4.1 UN3367 I Prohibited Prohibited

Trinitrobenzene, dry or wetted with

less than 30

percent water, by mass

1.1D UN0214 II Prohibited Prohibited

Trinitrobenzenesulfonic acid 1.1D UN0386 II Prohibited Prohibited

Trinitrobenzoic acid, dry or wetted

with less than 30

percent water, by

mass

1.1D UN0215 II Prohibited Prohibited

Trinitrobenzoic acid, wetted with not

less than 10

percent water, by mass

4.4 UN3368 I Prohibited Prohibited

Trinitrobenzoic acid, wetted with not

less than 30 percent water, by mass

4.1 UN1355 I Prohibited Prohibited

Trinitrochlorobenzene or Picryl

chloride

1.1D UN0155 II Prohibited Prohibited

Trinitrochlorobenzene (picryl

chloride), wetted, with not less than

percent water by mass

4.1 UN3365 I Prohibited Prohibited

Trinitroethanol Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitroethylnitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitrofluorenone 1.1D UN0387 II Prohibited Prohibited

Trinitromethane Forbidden Prohibited Prohibited

Trinitronaphthalene 1.1D UN0217 II Prohibited Prohibited

1,3,5-Trinitronaphthalene Forbidden Prohibited Prohibited

Trinitrophenetole 1.1D UN0218 II Prohibited Prohibited

Trinitrophenol (picric acid), wetted

with not less than 10 percent water

by mass

4.1 UN3364 I Prohibited Prohibited

Trinitrophenol or Picric acid, dry or

wetted with less than 30 percent

water, by mass

1.1D UN0154 II Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

280 Publication 52

Trinitrophenol, wetted with not less

than 30 percent water, by mass

4.1 UN1344 I Prohibited Prohibited

2,4,6-Trinitrophenyl guanidine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

2,4,6-Trinitrophenyl nitramine Forbidden Prohibited Prohibited Prohibited Prohibited

2,4,6-Trinitrophenyl trimethylol

methyl nitramine trinitrate (dry)

Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitrophenylmethylnitramine or

Tetryl

1.1D UN0208 II Prohibited Prohibited

Trinitroresorcinol or Styphnic acid,

dry or wetted with less than

percent water, or mixture of

alcohol and water, by mass

1.1D UN0219 II Prohibited Prohibited

Trinitroresorcinol, wetted or Styphnic

acid, wetted with not less than

percent water, or mixture of

alcohol and water, by mass

1.1D UN0394 II Prohibited Prohibited

2,4,6-Trinitroso-3-methyl

nitraminoanisole

Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitrotetramine cobalt nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Trinitrotoluene or TNT, dry or wetted

with less than 30 percent water, by

mass

1.1D UN0209 II Prohibited Prohibited

Trinitrotoluene (TNT) wetted, with not

less than 10 percent water by mass

4.1 UN3366 I Prohibited Prohibited

Trinitrotoluene and Trinitrobenzene

mixtures or TNT and trinitrobenzene

mixtures or TNT and

hexanitrostilbene mixtures or

Trinitrotoluene and

hexanitrostilbene mixtures

1.1D UN0388 II Prohibited Prohibited

Trinitrotoluene mixtures containing

Trinitrobenzene and

Hexanitrostilbene or TNT mixtures

containing trinitrobenzene and

hexanitrostilbene

1.1D UN0389 II Prohibited Prohibited

Trinitrotoluene wetted with not less

than 30 percent water, by mass

4.1 UN1356 I Prohibited Prohibited

Tripropylamine 3 UN2260 III Prohibited 3A

Tripropylene 3 UN2057 II, III Prohibited 3A

Tris, bis-bifluoroamino diethoxy

propane (TVOPA)

Forbidden Prohibited Prohibited Prohibited Prohibited

Tris-(1-aziridinyl)phosphine oxide,

solution

6.1 UN2501 II Prohibited Prohibited

Tris-(1-aziridinyl)phosphine oxide,

solution

6.1 UN2501 III 6A 6A

Tritonal 1.1D UN0390 II Prohibited Prohibited

Tungsten hexafluoride 2.3 UN2196 n/a Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 281

Turpentine 3 UN1299 III Prohibited 3A

Turpentine substitute 3 UN1300 I Prohibited Prohibited

Turpentine substitute 3 UN1300 II, III Prohibited 3A

Undecane 3 UN2330 III Prohibited 3A

Urea hydrogen peroxide 5.1 UN1511 III 5A 5A

Urea nitrate, dry or wetted with less

than 20

percent water, by mass

1.1D UN0220 II Prohibited Prohibited

Urea nitrate, wetted with not less

than 10 percent water, by mass

4.1 UN3370 I Prohibited Prohibited

Urea nitrate, wetted with not less

than 20 percent water, by mass

4.1 UN1357 I Prohibited Prohibited

Urea peroxide, see Urea hydrogen

peroxide

Valeraldehyde 3 UN2058 II Prohibited 3A

Valeric acid, see Corrosive liquids,

n.o.s.

Valeryl chloride 8 UN2502 II 8A 8A

Vanadium compound, n.o.s. 6.1 UN3285 I, II

Vanadium compound, n.o.s. 6.1 UN3285 III 6A 6A

Vanadium oxytrichloride 8 UN2443 II 8A 8A

Vanadium pentoxide, non-fused form 6.1 UN2862 III 6A 6A

Vanadium tetrachloride 8 UN2444 I Prohibited Prohibited

Vanadium trichloride 8 UN2475 III 8A 8A

Vanadyl sulfate 6.1 UN2931 II Prohibited Prohibited

Vehicle, flammable gas powered or

Vehicle, fuel cell, flammable gas

powered

9 UN3166 n/a Prohibited Prohibited

Vehicle, flammable liquid powered or

Vehicle, fuel cell, flammable liquid

powered

9 UN3166 n/a Prohibited Prohibited

Very signal cartridge, see Cartridges,

signal

Vinyl acetate, stabilized 3 UN1301 II Prohibited 3A

Vinyl bromide, stabilized 2.1 UN1085 n/a Prohibited 2A

Vinyl butyrate, stabilized 3 UN2838 II Prohibited 3A

Vinyl chloride, stabilized 2.1 UN1086 n/a Prohibited 2A

Vinyl chloroacetate 6.1 UN2589 II Prohibited Prohibited

Vinyl ethyl ether, stabilized 3 UN1302 I Prohibited Prohibited

Vinyl fluoride, stabilized 2.1 UN1860 n/a Prohibited 2A

Vinyl isobutyl ether, stabilized 3 UN1304 II Prohibited 3A

Vinyl methyl ether, stabilized 2.1 UN1087 n/a Prohibited 2A

Vinyl nitrate polymer Forbidden Prohibited Prohibited Prohibited Prohibited

Vinylidene chloride, stabilized 3 UN1303 I Prohibited 3A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

282 Publication 52

Vinylpyridines, stabilized 6.1 UN3073 II Prohibited Prohibited

Vinyltoluenes, stabilized 3 UN2618 III Prohibited 3A

Vinyltrichlorosilane, stabilized 3 UN1305 I Prohibited Prohibited

Warheads, rocket with burster or

expelling charge

1.4D UN0370 II Prohibited Prohibited

Warheads, rocket with burster or

expelling charge

1.4F UN0371 II Prohibited Prohibited

Warheads, rocket with bursting

charge

1.1D UN0286 II Prohibited Prohibited

Warheads, rocket with bursting

charge

1.1F UN0369 II Prohibited Prohibited

Warheads, rocket with bursting

charge

1.2D UN0287 II Prohibited Prohibited

Warheads, torpedo with bursting

charge

1.1D UN0221 II Prohibited Prohibited

Water-reactive liquid, corrosive,

n.o.s.

4.3 UN3129 I Prohibited Prohibited

Water-reactive liquid, corrosive,

n.o.s.

4.3 UN3129 II, III Prohibited 4A

Water-reactive liquid, n.o.s. 4.3 UN3148 I, II, III Prohibited Prohibited

Water-reactive liquid, toxic, n.o.s. 4.3 UN3130 I, II, III Prohibited Prohibited

Water-reactive solid, corrosive, n.o.s. 4.3 UN3131 I Prohibited Prohibited

Water-reactive solid, corrosive, n.o.s. 4.3 UN3131 II, III Prohibited 4A

Water-reactive solid, flammable,

n.o.s.

4.3 UN3132 I Prohibited Prohibited

Water-reactive solid, flammable,

n.o.s.

4.3 UN3132 II, III Prohibited 4A

Water-reactive solid, n.o.s. 4.3 UN2813 I Prohibited Prohibited

Water-reactive solid, n.o.s. 4.3 UN2813 II, III Prohibited 4A

Water-reactive solid, oxidizing, n.o.s. 4.3 UN3133 II, III Prohibited Prohibited

Water-reactive solid, self-heating,

n.o.s.

4.3 UN3135 I, II, III Prohibited Prohibited

Water-reactive solid, toxic, n.o.s. 4.3 UN3134 I Prohibited Prohibited

Water-reactive solid, toxic, n.o.s. 4.3 UN3134 II, III Prohibited 4A

Wheel chair, electric, see Battery

powered vehicle or Battery

powered equipment

White acid, see Hydroflouric acid

White asbestos (chrysotile, actinolite,

anthophyllite, tremolite)

9 UN2590 III Prohibited 9C

Wood preservatives, liquid 3 UN1306 II, III Prohibited 3A

Wool waste, wet 4.2 UN1387 III Prohibited Prohibited

Xanthates 4.2 UN3342 II, III Prohibited Prohibited

Xenon, compressed 2.2 UN2036 n/a 2B 2B

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Hazardous Materials Table: Postal Service Mailability Guide Appendix A

September 7, 2023 283

Xenon, refrigerated liquid (cryogenic

liquids)

2.2 UN2591 n/a Prohibited Prohibited

Xylenes 3 UN1307 II, III Prohibited Prohibited

Xylenols, solid 6.1 UN2261 II Prohibited Prohibited

Xylenols, liquid 6.1 UN3430 II Prohibited Prohibited

Xylidines, solid 6.1 UN3452 II Prohibited Prohibited

Xylidines, liquid 6.1 UN1711 II Prohibited Prohibited

Xylyl bromide, liquid 6.1 UN1701 II Prohibited Prohibited

Xylyl bromide, solid 6.1 UN3417 II Prohibited Prohibited

p-Xylyl diazide Forbidden Prohibited Prohibited Prohibited Prohibited

Zinc ammonium nitrite 5.1 UN1512 II Prohibited Prohibited

Zinc arsenate or Zinc arsenite or Zinc

arsenate and zinc arsenite mixtures

6.1 UN1712 II Prohibited Prohibited

Zinc ashes 4.3 UN1435 III Prohibited 4A

Zinc bisulfite solution, see Bisulfites,

aqueous solutions, n.o.s.

Zinc bromate 5.1 UN2469 III 5A 5A

Zinc chlorate 5.1 UN1513 II 5A 5A

Zinc chloride, anhydrous 8 UN2331 III Prohibited Prohibited

Zinc chloride, solution 8 UN1840 III 8A 8A

Zinc cyanide 6.1 UN1713 I Prohibited Prohibited

Zinc dithionite or Zinc hydrosulfite 9 UN1931 III Prohibited 9C

Zinc fluorosilicate 6.1 UN2855 III 6A 6A

Zinc hydrosulfite, see Zinc dithionite

Zinc muriate solution, see Zinc

chloride, solution

Zinc nitrate 5.1 UN1514 II 5A 5A

Zinc permanganate 5.1 UN1515 II 5A 5A

Zinc peroxide 5.1 UN1516 II 5A 5A

Zinc phosphide 4.3 UN1714 I Prohibited Prohibited

Zinc powder or Zinc dust 4.3 UN1436 I, II, III Prohibited Prohibited

Zinc resinate 4.1 UN2714 III Prohibited 4A

Zinc selenate, see Selenates or

Selenites

Zinc selenite, see Selenates or

Selenites

Zinc silicofluoride, see Zinc

fluorosilicate

Zirconium, dry, coiled wire, finished

metal sheets, strip (thinner than

254 microns but not thinner than

microns)

4.1 UN2858 III Prohibited 4A

Zirconium, dry, finished sheets, strip

or coiled wire

4.2 UN2009 III Prohibited Prohibited

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

Appendix A Hazardous, Restricted, and Perishable Mail

284 Publication 52

Zirconium hydride 4.1 UN1437 II Prohibited Prohibited

Zirconium nitrate 5.1 UN2728 III 5A 5A

Zirconium picramate, dry or wetted

with less than 20 percent water, by

mass

1.3C UN0236 II Prohibited Prohibited

Zirconium picramate, wetted with not

less than 20 percent water, by mass

4.1 UN1517 I Prohibited Prohibited

Zirconium powder, dry 4.2 UN2008 I, II, III Prohibited Prohibited

Zirconium powder, wetted with not

less than 25 percent water (a visible

excess of water must be present) (a)

mechanically produced, particle size

less than 53 microns; (b) chemically

produced, particle size less than

840 microns

4.1 UN1358 II Prohibited Prohibited

Zirconium scrap 4.2 UN1932 III Prohibited Prohibited

Zirconium suspended in a liquid 3 UN1308 I, II Prohibited Prohibited

Zirconium suspended in a liquid 3 UN1308 III Prohibited 3A

Zirconium tetrachloride 8 UN2503 III 8A 8A

Hazardous Materials Descriptions

and Proper Shipping Names (a)

Hazard

Class (b)

Number (c)

DOT

PG (d)

Domestic

Mail Air (e)

Domestic

Mail

Surface (f)

September 7, 2023 285

Appendix B

Numerical Listing of Proper Shipping Names

by Identification (ID) Number

This appendix contains a numerical list of the United Nations (UN) and North

American (NA) identification (ID) numbers for proper shipping names of the

hazardous materials listed alphabetically in Appendix

A. The text appearing

in italic type is not part of the proper shipping name of the hazardous

material and is used for descriptive or references purposes only. This

numerical list can be used to determine the proper shipping name of a

hazardous material when the UN or NA number is known. Once the proper

shipping name is known, it can be referenced back to Appendix

A to

determine the mailability of the hazardous material.

UN0004 Ammonium picrate, dry or wetted with less than 10 percent water, by mass

UN0005 Cartridges for weapons, with bursting charge

UN0006 Cartridges for weapons, with bursting charge

UN0007 Cartridges for weapons, with bursting charge

UN0009 Ammunition, incendiary with or without burster, expelling charge, or propelling charge

UN0010 Ammunition, incendiary with or without burster, expelling charge, or propelling charge

UN0012 Cartridges for weapons, inert projectile or Cartridges, small arms

UN0014 Cartridges for weapons, blank or Cartridges, small arms, blank

UN0015 Ammunition, smoke, with or without burster, expelling charge, or propelling charge

UN0016 Ammunition, smoke, with or without burster, expelling charge, or propelling charge

UN0018 Ammunition, tear–producing with burster, expelling charge, or propelling charge

UN0019 Ammunition, tear–producing with burster, expelling charge, or propelling charge

UN0020 Ammunition, toxic with burster, expelling charge, or propelling charge

UN0021 Ammunition, toxic with burster, expelling charge, or propelling charge

NA0027 Black powder for small arms

UN0027 Black powder or Gunpowder, granular or as a meal

UN0028 Black powder, compressed or Gunpowder, compressed or Black powder, in pellets or Gunpowder, in

pellets

UN0029 Detonators, non–electric, for blasting

UN0030 Detonators, electric, for blasting

UN0033 Bombs, with bursting charge

UN0034 Bombs, with bursting charge

UN0035 Bombs, with bursting charge

UN0037 Bombs, photo–flash

UN0038 Bombs, photo–flash

UN0039 Bombs, photo–flash

Appendix B Hazardous, Restricted, and Perishable Mail

286 Publication 52

UN0042 Boosters, without detonator

UN0043 Bursters, explosive

UN0044 Primers, cap type

UN0048 Charges, demolition

UN0049 Cartridges, flash

UN0050 Cartridges, flash

UN0054 Cartridges, signal

UN0055 Cases, cartridge, empty with primer

UN0056 Charges, depth

UN0059 Charges, shaped, without detonator

UN0060 Charges, supplementary explosive

UN0065 Cord, detonating, flexible

UN0066 Cord, igniter

UN0070 Cutters, cable, explosive

UN0072 Cyclotrimethylenetrinitramine, wetted or Cyclonite, wetted or Hexogen, wetted or RDX, wetted with

not less than 15 percent water by mass

UN0073 Detonators for ammunition

UN0074 Diazodinitrophenol, wetted with not less than 40 percent water or mixture of alcohol and water, by

mass

UN0075 Diethyleneglycol dinitrate, desensitized with not less than 25 percent non–volatile water–insoluble

phlegmatizer, by mass

UN0076 Dinitrophenol, dry or wetted with less than 15 percent water, by mass

UN0077 Dinitrophenolates alkali metals, dry or wetted with less than 15 percent water, by mass

UN0078 Dinitroresorcinol, dry or wetted with less than 15 percent water, by mass

UN0079 Hexanitrodiphenylamine or Dipicrylamine or Hexyl

UN0081 Explosive, blasting, type A

UN0082 Explosive, blasting, type B

UN0083 Explosive, blasting, type C

UN0084 Explosive, blasting, type D

UN0092 Flares, surface

UN0093 Flares, aerial

UN0094 Flash powder

UN0099 Fracturing devices, explosives, without detonators for oil wells

UN0101 Fuse, non–detonating (instantaneous or quickmatch)

UN0102 Cord detonating or Fuse detonating metal clad

UN0103 Fuse, igniter tubular metal clad

UN0104 Cord, detonating, mild effect or Fuse, detonating, mild effect metal clad

UN0105 Fuse, safety

UN0106 Fuzes, detonating

UN0107 Fuzes, detonating

UN0110 Grenades, practice, hand or rifle

UN0113 Guanyl nitrosaminoguanylidene hydrazine, wetted with not less than 30 percent water, by mass

UN0114 Guanyl nitrosaminoguanyltetrazene, wetted or Tetrazene, wetted with not less than 30 percent water

or mixture of alcohol and water, by mass

UN0118 Hexolite, or Hexotol dry or wetted with less than 15 percent water, by mass

UN0121 Igniters

NA0124 Jet, perforating guns, charged oil well, with detonator

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September 7, 2023 287

UN0124 Jet, perforating guns, charged oil well, without detonator

UN0129 Lead azide, wetted with not less than 20 percent water or mixture of alcohol and water, by mass

UN0130 Lead styphnate, wetted or Lead trinitroresorcinate, wetted with not less than 20 percent water or

mixture of alcohol and water, by mass

UN0131 Lighters, fuse

UN0132 Deflagrating metal salts of aromatic nitroderivatives, n.o.s.

UN0133 Mannitol hexanitrate, wetted or Nitromannite, wetted with not less than 40 percent water, or mixture

of alcohol and water, by mass

UN0135 Mercury fulminate, wetted with not less than 20 percent water, or mixture of alcohol and water, by

mass

UN0136 Mines with bursting charge

UN0137 Mines with bursting charge

UN0138 Mines with bursting charge

UN0143 Nitroglycerin, desensitized with not less than 40 percent non–volatile water insoluble phlegmatizer, by

mass

UN0144 Nitroglycerin, solution in alcohol, with more than 1 percent but not more than 10 percent nitroglycerin

UN0146 Nitrostarch, dry or wetted with less than 20 percent water, by mass

UN0147 Nitro urea

UN0150 Pentaerythrite tetranitrate, wetted or Pentaerythritol tetranitrate, wetted or PETN, wetted with not less

than 25 percent water, by mass, or Pentaerythrite tetranitrate, or Pentaerythritol tetranitrate, or PETN,

desensitized with not less than 15 percent

UN0151 Pentolite, dry or wetted with less than 15 percent water, by mass

UN0153 Trinitroaniline or Picramide

UN0154 Trinitrophenol or Picric acid, dry or wetted with less than 30 percent water, by mass

UN0155 Trinitrochlorobenzene or Picryl chloride

UN0159 Powder cake, wetted or Powder paste, wetted with not less than 25 percent water, by mass

UN0160 Powder, smokeless

UN0161 Powder, smokeless

UN0167 Projectiles, with bursting charge

UN0168 Projectiles, with bursting charge

UN0169 Projectiles, with bursting charge

UN0171 Ammunition, illuminating with or without burster, expelling charge, or propelling charge

UN0173 Release devices, explosive

UN0174 Rivets, explosive

UN0180 Rockets, with bursting charge

UN0181 Rockets, with bursting charge

UN0182 Rockets, with bursting charge

UN0183 Rockets, with inert head

UN0186 Rocket motors

UN0190 Samples, explosive, other than initiating explosives

UN0191 Signal devices, hand

UN0192 Signals, railway track, explosive

UN0193 Signals, railway track, explosive

UN0194 Signals, distress, ship

UN0195 Signals, distress, ship

UN0196 Signals, smoke

UN0197 Signals, smoke

Appendix B Hazardous, Restricted, and Perishable Mail

288 Publication 52

UN0204 Sounding devices, explosive

UN0207 Tetranitroaniline

UN0208 Trinitrophenylmethylnitramine or Tetryl

UN0209 Trinitrotoluene or TNT, dry or wetted with less than 30 percent water, by mass

UN0212 Tracers for ammunition

UN0213 Trinitroanisole

UN0214 Trinitrobenzene, dry or wetted with less than 30 percent water, by mass

UN0215 Trinitrobenzoic acid, dry or wetted with less than 30 percent water, by mass

UN0216 Trinitro–meta–cresol

UN0217 Trinitronaphthalene

UN0218 Trinitrophenetole

UN0219 Trinitroresorcinol or Styphnic acid, dry or wetted with less than 20 percent water, or mixture of alcohol

and water, by mass

UN0220 Urea nitrate, dry or wetted with less than 20 percent water, by mass

UN0221 Warheads, torpedo with bursting charge

UN0222 Ammonium nitrate, with more than 0.2 percent combustible substances, including any organic

substance calculated as carbon, to the exclusion of any other added substance

UN0224 Barium azide, dry or wetted with less than 50 percent water, by mass

UN0225 Boosters with detonator

UN0226 Cyclotetramethylenetetranitramine, wetted or HMX, wetted or Octogen, wetted with not less than 15

percent water, by mass

UN0234 Sodium dinitro–o–cresolate, dry or wetted with less than 15 percent water, by mass

UN0235 Sodium picramate, dry or wetted with less than 20 percent water, by mass

UN0236 Zirconium picramate, dry or wetted with less than 20 percent water, by mass

UN0237 Charges, shaped, flexible, linear

UN0238 Rockets, line–throwing

UN0240 Rockets, line–throwing

UN0241 Explosive, blasting, type E

UN0242 Charges, propelling, for cannon

UN0243 Ammunition, incendiary, white phosphorus, with burster, expelling charge, or propelling charge

UN0244 Ammunition, incendiary, white phosphorus, with burster, expelling charge, or propelling charge

UN0245 Ammunition smoke, white phosphorus with burster, expelling charge, or propelling charge

UN0246 Ammunition, smoke, white phosphorus with burster, expelling charge, or propelling charge

UN0247 Ammunition, incendiary liquid or gel, with burster, expelling charge, or propelling charge

UN0248 Contrivances, water–activated, with burster, expelling charge, or propelling charge

UN0249 Contrivances, water–activated, with burster, expelling charge, or propelling charge

UN0250 Rocket motors with hypergolic liquids with or without an expelling charge

UN0254 Ammunition, illuminating with or without burster, expelling charge, or propelling charge

UN0255 Detonators, electric, for blasting

UN0257 Fuzes, detonating

UN0266 Octolite or Octol, dry or wetted with less than 15 percent water, by mass

UN0267 Detonators, non–electric, for blasting

UN0268 Boosters with detonator

UN0271 Charges, propelling

UN0272 Charges, propelling

UN0275 Cartridges, power device

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September 7, 2023 289

NA0276 Model rocket motor

UN0276 Cartridges, power device

UN0277 Cartridges, oil well

UN0278 Cartridges, oil well

UN0279 Charges, propelling, for cannon

UN0280 Rocket motors

UN0281 Rocket motors

UN0282 Nitroguanidine or Picrite, dry or wetted with less than 20 percent water, by mass

UN0283 Boosters, without detonator

UN0284 Grenades, hand or rifle, with bursting charge

UN0285 Grenades, hand or rifle, with bursting charge

UN0286 Warheads, rocket with bursting charge

UN0287 Warheads, rocket with bursting charge

UN0288 Charges, shaped, flexible, linear

UN0289 Cord, detonating, flexible

UN0290 Cord, detonating or Fuse, detonating metal clad

UN0291 Bombs, with bursting charge

UN0292 Grenades, hand or rifle, with bursting charge

UN0293 Grenades, hand or rifle, with bursting charge

UN0294 Mines with bursting charge

UN0295 Rockets, with bursting charge

UN0296 Sounding devices, explosive

UN0297 Ammunition, illuminating with or without burster, expelling charge, or propelling charge

UN0299 Bombs, photo–flash

UN0300 Ammunition, incendiary with or without burster, expelling charge, or propelling charge

UN0301 Ammunition, tear–producing with burster, expelling charge, or propelling charge

UN0303 Ammunition, smoke, with or without burster, expelling charge, or propelling charge

UN0305 Flash powder

UN0306 Tracers for ammunition

UN0312 Cartridges, signal

UN0313 Signals, smoke

UN0314 Igniters

UN0315 Igniters

UN0316 Fuzes, igniting

UN0317 Fuzes, igniting

UN0318 Grenades, practice, hand or rifle

UN0319 Primers, tubular

UN0320 Primers, tubular

UN0321 Cartridges for weapons, with bursting charge

UN0322 Rocket motors with hypergolic liquids with or without an expelling charge

NA0323 Model rocket motor

UN0323 Cartridges, power device

UN0324 Projectiles, with bursting charge

UN0325 Igniters

UN0326 Cartridges for weapons, blank

UN0327 Cartridges for weapons, blank or Cartridges, small arms, blank

Appendix B Hazardous, Restricted, and Perishable Mail

290 Publication 52

UN0328 Cartridges for weapons, inert projectile

UN0329 Torpedoes with bursting charge

UN0330 Torpedoes with bursting charge

NA0331 Ammonium nitrate–fuel oil mixture containing only prilled ammonium nitrate and fuel oil

UN0331 Explosive, blasting, type B or Agent blasting, Type B

UN0332 Explosive, blasting, type E or Agent blasting, Type E

UN0333 Fireworks

UN0334 Fireworks

UN0335 Fireworks

UN0336 Fireworks

NA0337 Toy caps

UN0337 Fireworks

UN0338 Cartridges for weapons, blank or Cartridges, small arms, blank

UN0339 Cartridges for weapons, inert projectile or Cartridges, small arms

UN0340 Nitrocellulose, dry or wetted with less than 25 percent water (or alcohol), by mass

UN0341 Nitrocellulose, unmodified or plasticized with less than 18 percent plasticizing substance, by mass

UN0342 Nitrocellulose, wetted with not less than 25 percent alcohol, by mass

UN0343 Nitrocellulose, plasticized with not less than 18 percent plasticizing substance, by mass

UN0344 Projectiles, with bursting charge

UN0345 Projectiles, inert with tracer

UN0346 Projectiles, with burster or expelling charge

UN0347 Projectiles, with burster or expelling charge

UN0348 Cartridges for weapons, with bursting charge

NA0349 Grenades, empty primed

UN0349 Articles, explosive, n.o.s.

UN0350 Articles, explosive, n.o.s.

UN0351 Articles, explosive, n.o.s.

UN0352 Articles, explosive, n.o.s.

UN0353 Articles, explosive, n.o.s.

UN0354 Articles, explosive, n.o.s.

UN0355 Articles, explosive, n.o.s.

UN0356 Articles, explosive, n.o.s.

UN0357 Substances, explosive, n.o.s.

UN0358 Substances, explosive, n.o.s.

UN0359 Substances, explosive, n.o.s.

UN0360 Detonator assemblies, non–electric for blasting

UN0361 Detonator assemblies, non–electric for blasting

UN0362 Ammunition, practice

UN0363 Ammunition, proof

UN0364 Detonators for ammunition

UN0365 Detonators for ammunition

UN0366 Detonators for ammunition

UN0367 Fuzes, detonating

UN0368 Fuzes, igniting

UN0369 Warheads, rocket with bursting charge

UN0370 Warheads, rocket with burster or expelling charge

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September 7, 2023 291

UN0371 Warheads, rocket with burster or expelling charge

UN0372 Grenades, practice, hand or rifle

UN0373 Signal devices, hand

UN0374 Sounding devices, explosive

UN0375 Sounding devices, explosive

UN0376 Primers, tubular

UN0377 Primers, cap type

UN0378 Primers, cap type

UN0379 Cases, cartridges, empty with primer

UN0380 Articles, pyrophoric

UN0381 Cartridges, power device

UN0382 Components, explosive train, n.o.s.

UN0383 Components, explosive train, n.o.s.

UN0384 Components, explosive train, n.o.s.

UN0385 5–Nitrobenzotriazol

UN0386 Trinitrobenzenesulfonic acid

UN0387 Trinitrofluorenone

UN0388 Trinitrotoluene and Trinitrobenzene mixtures or TNT and trinitrobenzene mixtures or TNT and

hexanitrostilbene mixtures or Trinitrotoluene and hexanitrostilbene mixtures

UN0389 Trinitrotoluene mixtures containing Trinitrobenzene and Hexanitrostilbene or TNT mixtures containing

trinitrobenzene and hexanitrostilbene

UN0390 Tritonal

UN0391 RDX and HMX mixtures, wetted with not less than 15 percent water by mass or RDX and HMX

mixtures, desensitized with not less than 10 percent phlegmatizer by mass

UN0392 Hexanitrostilbene

UN0393 Hexotonal

UN0394 Trinitroresorcinol, wetted or Styphnic acid, wetted with not less than 20 percent water, or mixture of

alcohol and water, by mass

UN0395 Rocket motors, liquid fueled

UN0396 Rocket motors, liquid fueled

UN0397 Rockets, liquid fueled with bursting charge

UN0398 Rockets, liquid fueled with bursting charge

UN0399 Bombs with flammable liquid, with bursting charge

UN0400 Bombs with flammable liquid, with bursting charge

UN0401 Dipicryl sulfide, dry or wetted with less than 10 percent water, by mass

UN0402 Ammonium perchlorate

UN0403 Flares, aerial

UN0404 Flares, aerial

UN0405 Cartridges, signal

UN0406 Dinitrosobenzene

UN0407 Tetrazol–1–acetic acid

UN0408 Fuzes, detonating, with protective features

UN0409 Fuzes, detonating, with protective features

UN0410 Fuzes, detonating, with protective features

UN0411 Pentaerythrite tetranitrate or Pentaerythritol tetranitrate or PETN, with not less than 7 percent wax by

mass

UN0412 Cartridges for weapons, with bursting charge

Appendix B Hazardous, Restricted, and Perishable Mail

292 Publication 52

UN0413 Cartridges for weapons, blank

UN0414 Charges, propelling, for cannon

UN0415 Charges, propelling

UN0417 Cartridges for weapons, inert projectile or Cartridges, small arms

UN0418 Flares, surface

UN0419 Flares, surface

UN0420 Flares, aerial

UN0421 Flares, aerial

UN0424 Projectiles, inert with tracer

UN0425 Projectiles, inert with tracer

UN0426 Projectiles, with burster or expelling charge

UN0427 Projectiles, with burster or expelling charge

UN0428 Articles, pyrotechnic for technical purposes

UN0429 Articles, pyrotechnic for technical purposes

UN0430 Articles, pyrotechnic for technical purposes

UN0431 Articles, pyrotechnic for technical purposes

UN0432 Articles, pyrotechnic for technical purposes

UN0433 Powder cake, wetted or Powder paste, wetted with not less than 17 percent alcohol by mass

UN0434 Projectiles, with burster or expelling charge

UN0435 Projectiles, with burster or expelling charge

UN0436 Rockets, with expelling charge

UN0437 Rockets, with expelling charge

UN0438 Rockets, with expelling charge

UN0439 Charges, shaped, without detonator

UN0440 Charges, shaped, without detonator

UN0441 Charges, shaped, without detonator

UN0442 Charges, explosive, commercial without detonator

UN0443 Charges, explosive, commercial without detonator

UN0444 Charges, explosive, commercial without detonator

UN0445 Charges, explosive, commercial without detonator

UN0446 Cases, combustible, empty, without primer

UN0447 Cases, combustible, empty, without primer

UN0448 5–Mercaptotetrazol–1–acetic acid

UN0449 Torpedoes, liquid fueled, with or without bursting charge

UN0450 Torpedoes, liquid fueled, with inert head

UN0451 Torpedoes with bursting charge

UN0452 Grenades, practice, hand or rifle

UN0453 Rockets, line–throwing

UN0454 Igniters

UN0455 Detonators, non–electric, for blasting

UN0456 Detonators, electric, for blasting

UN0457 Charges, bursting, plastics bonded

UN0458 Charges, bursting, plastics bonded

UN0459 Charges, bursting, plastics bonded

UN0460 Charges, bursting, plastics bonded

UN0461 Components, explosive train, n.o.s.

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September 7, 2023 293

UN0462 Articles, explosive, n.o.s.

UN0463 Articles, explosive, n.o.s.

UN0464 Articles, explosive, n.o.s.

UN0465 Articles, explosive, n.o.s.

UN0466 Articles, explosive, n.o.s.

UN0467 Articles, explosive, n.o.s.

UN0468 Articles, explosive, n.o.s.

UN0469 Articles, explosive, n.o.s.

UN0470 Articles, explosive, n.o.s.

UN0471 Articles, explosive, n.o.s.

UN0472 Articles, explosive, n.o.s.

NA0473 Barium styphnate or Lead mononitroresorcinate

UN0473 Substances, explosive, n.o.s.

UN0474 Substances, explosive, n.o.s.

UN0475 Substances, explosive, n.o.s.

UN0476 Substances, explosive, n.o.s.

UN0477 Substances, explosive, n.o.s.

UN0478 Substances, explosive, n.o.s.

UN0479 Substances, explosive, n.o.s.

UN0480 Substances, explosive, n.o.s.

UN0481 Substances, explosive, n.o.s.

UN0482 Substances, explosive, very insensitive, n.o.s., or Substances, EVI, n.o.s.

UN0483 Cyclotrimethylenetrinitramine, desensitized or Cyclonite, desensitized or Hexogen, desensitized or

RDX, desensitized

UN0484 Cyclotetramethylenetetranitramine, desensitized or Octogen, desensitized or HMX, desensitized

UN0485 Substances, explosive, n.o.s.

UN0486 Articles, explosive, extremely insensitive or Articles, EEI

UN0487 Signals, smoke

UN0488 Ammunition, practice

UN0489 Dinitroglycoluril or Dingu

UN0490 Nitrotriazolone or NTO

UN0491 Charges, propelling

UN0492 Signals, railway track, explosive

UN0493 Signals, railway track, explosive

NA0494 Jet, perforating guns, charged oil well, with detonator

UN0494 Jet, perforating guns, charged oil well, without detonator

UN0495 Propellant, liquid

UN0496 Octonal

UN0497 Propellant, liquid

UN0498 Propellant, solid

UN0499 Propellant, solid

UN0500 Detonator assemblies, non–electric for blasting

UN0503 Air bag inflators, or Air bag modules, or Seatbelt pretensioners

UN0504 1H-Tetrazole

UN1001 Acetylene, dissolved

UN1002 Air, compressed

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294 Publication 52

UN1003 Air, refrigerated liquid, (cryogenic liquid) or Air, refrigerated liquid (cryogenic liquid) non–pressurized

UN1005 Ammonia, anhydrous

UN1006 Argon, compressed

UN1008 Boron trifluoride

UN1009 Bromotrifluoromethane or Refrigerant gas, R 13B1

UN1010 Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40%

butadienes

UN1011 Butane see also Petroleum gases, liquified

UN1012 Butylene see also Petroleum gases, liquified

UN1013 Carbon dioxide

UN1016 Carbon monoxide, compressed

UN1017 Chlorine

UN1018 Chlorodifluoromethane or Refrigerant gas R 22

UN1020 Chloropentafluoroethane or Refrigerant gas R 115

UN1021 1–Chloro–1,2,2,2–tetrafluoroethane or Refrigerant gas R 124

UN1022 Chlorotrifluoromethane or Refrigerant gas R 13

UN1023 Coal gas, compressed

UN1026 Cyanogen

UN1027 Cyclopropane

UN1028 Dichlorodifluoromethane or Refrigerant gas R 12

UN1029 Dichlorofluoromethane or Refrigerant gas R 21

UN1030 1,1–Difluoroethane or Refrigerant gas R 152a

UN1032 Dimethylamine, anhydrous

UN1033 Dimethyl ether

UN1035 Ethane

UN1036 Ethylamine

UN1037 Ethyl chloride

UN1038 Ethylene, refrigerated liquid (cryogenic liquid)

UN1039 Ethyl methyl ether

UN1040 Ethylene oxide or Ethylene oxide with nitrogen up to a total pressure of 1MPa (10 bar) at 50° C

UN1041 Ethylene oxide and carbon dioxide mixtures with more than 9 percent but not more than 87 percent

ethylene oxide

UN1043 Fertilizer ammoniating solution with free ammonia

UN1044 Fire extinguishers containing compressed or liquified gas

UN1045 Fluorine, compressed

UN1046 Helium, compressed

UN1048 Hydrogen bromide, anhydrous

UN1049 Hydrogen, compressed

UN1050 Hydrogen chloride, anhydrous

UN1051 Hydrogen cyanide, stabilized with less than 3 percent water

UN1052 Hydrogen fluoride, anhydrous

UN1053 Hydrogen sulfide

UN1055 Isobutylene see also Petroleum gases, liquified

UN1056 Krypton, compressed

UN1057 Lighters or Lighter refills cigarettes, containing flammable gas

UN1058 Liquified gases, nonflammable charged with nitrogen, carbon dioxide, or air

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September 7, 2023 295

UN1060 Methyl acetylene and propadiene mixtures, stabilized

UN1061 Methylamine, anhydrous

UN1062 Methyl bromide

UN1063 Methyl chloride, or Refrigerant gas R 40

UN1064 Methyl mercaptan

UN1065 Neon, compressed

UN1066 Nitrogen, compressed

UN1067 Dinitrogen tetroxide

UN1069 Nitrosyl chloride

UN1070 Nitrous oxide

UN1071 Oil gas, compressed

UN1072 Oxygen, compressed

UN1073 Oxygen, refrigerated liquid (cryogenic liquid)

UN1075 Petroleum gases, liquified or Liquified petroleum gas

UN1076 Phosgene

UN1077 Propylene see also Petroleum gases, liquified

UN1078 Refrigerant gases, n.o.s.

UN1079 Sulfur dioxide

UN1080 Sulfur hexafluoride

UN1081 Tetrafluoroethylene, stabilized

UN1082 Trifluorochloroethylene, stabilized

UN1083 Trimethylamine, anhydrous

UN1085 Vinyl bromide, stabilized

UN1086 Vinyl chloride, stabilized

UN1087 Vinyl methyl ether, stabilized

UN1088 Acetal

UN1089 Acetaldehyde

UN1090 Acetone

UN1091 Acetone oils

UN1092 Acrolein,stabilized

UN1093 Acrylonitrile, stabilized

UN1098 Allyl alcohol

UN1099 Allyl bromide

UN1100 Allyl chloride

UN1104 Amyl acetates

UN1105 Pentanols

UN1106 Amylamines

UN1107 Amyl chlorides

UN1108 1–Pentene (n–amylene)

UN1109 Amyl formates

UN1110 n–Amyl methyl ketone

UN1111 Amyl mercaptans

UN1112 Amyl nitrate

UN1113 Amyl nitrites

UN1114 Benzene

UN1120 Butanols

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296 Publication 52

UN1123 Butyl acetates

UN1125 n–Butylamine

UN1126 1–Bromobutane

UN1127 Chlorobutanes

UN1128 n–Butyl formate

UN1129 Butyraldehyde

UN1130 Camphor oil

UN1131 Carbon disulfide

UN1133 Adhesives, containing a flammable liquid

UN1134 Chlorobenzene

UN1135 Ethylene chlorohydrin

UN1136 Coal tar distillates, flammable

UN1139 Coating solution (includes surface treatments or coatings used for industrial or other purposes such as

vehicle undercoating, drum or barrel lining)

UN1143 Crotonaldehyde, or Crotonaldehyde, stabilized

UN1144 Crotonylene

UN1145 Cyclohexane

UN1146 Cyclopentane

UN1148 Diacetone alcohol

UN1149 Dibutyl ethers

UN1150 1,2–Dichloroethylene

UN1152 Dichloropentanes

UN1153 Ethylene glycol diethyl ether

UN1154 Diethylamine

UN1155 Diethyl ether or Ethyl ether

UN1156 Diethyl ketone

UN1157 Diisobutyl ketone

UN1158 Diisopropylamine

UN1159 Diisopropyl ether

UN1160 Dimethylamine solution

UN1161 Dimethyl carbonate

UN1162 Dimethyldichlorosilane

UN1163 Dimethylhydrazine, unsymmetrical

UN1164 Dimethyl sulfide

UN1165 Dioxane

UN1166 Dioxolane

UN1167 Divinyl ether, stabilized

UN1169 Extracts, aromatic, liquid

UN1170 Ethanol or Ethyl alcohol or Ethanol solutions or Ethyl alcohol solutions

UN1171 Ethylene glycol monoethyl ether

UN1172 Ethylene glycol monoethyl ether acetate

UN1173 Ethyl acetate

UN1175 Ethylbenzene

UN1176 Ethyl borate

UN1177 2–Ethylbutyl acetate

UN1178 2–Ethylbutyraldehyde

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September 7, 2023 297

UN1179 Ethyl butyl ether

UN1180 Ethyl butyrate

UN1181 Ethyl chloroacetate

UN1182 Ethyl chloroformate

UN1183 Ethyldichlorosilane

UN1184 Ethylene dichloride

UN1185 Ethyleneimine, stabilized

UN1188 Ethylene glycol monomethyl ether

UN1189 Ethylene glycol monomethyl ether acetate

UN1190 Ethyl formate

UN1191 Octyl aldehydes

UN1192 Ethyl lactate

UN1193 Ethyl methyl ketone or Methyl ethyl ketone

UN1194 Ethyl nitrate solutions

UN1195 Ethyl propionate

UN1196 Ethyltrichlorosilane

UN1197 Extracts, flavoring, liquid

UN1198 Formaldehyde, solutions, flammable

UN1199 Furaldehydes

UN1201 Fusel oil

UN1202 Diesel fuel

NA1203 Gasohol gasoline mixed with ethyl alcohol, with not more than 20 percent alcohol

UN1203 Gasoline

UN1204 Nitroglycerin, solution in alcohol, with not more than 1 percent nitroglycerin

UN1206 Heptanes

UN1207 Hexaldehyde

UN1208 Hexanes

UN1210 Printing ink, flammable

UN1212 Isobutanol or Isobutyl alcohol

UN1213 Isobutyl acetate

UN1214 Isobutylamine

UN1216 Isooctenes

UN1218 Isoprene, inhibited

UN1219 Isopropanol or Isopropyl alcohol

UN1220 Isopropyl acetate

UN1221 Isopropylamine

UN1222 Isopropyl nitrate

UN1223 Kerosene

UN1224 Ketones, liquid, n.o.s.

NA1226 Lighters for cigars, cigarettes, etc., with lighter fluids

UN1228 Mercaptans, liquid, flammable, toxic, n.o.s. or Mercaptan mixtures, liquid, flammable, toxic, n.o.s.

UN1229 Mesityl oxide

UN1230 Methanol

UN1231 Methyl acetate

UN1233 Methylamyl acetate

UN1234 Methylal

Appendix B Hazardous, Restricted, and Perishable Mail

298 Publication 52

UN1235 Methylamine, aqueous solution

UN1237 Methyl butyrate

UN1238 Methyl chloroformate

UN1239 Methyl chloromethyl ether

UN1242 Methyldichlorosilane

UN1243 Methyl formate

UN1244 Methylhydrazine

UN1245 Methyl isobutyl ketone

UN1246 Methyl isopropenyl ketone, inhibited

UN1247 Methyl methacrylate monomer, inhibited

UN1248 Methyl propionate

UN1249 Methyl propyl ketone

UN1250 Methyltrichlorosilane

UN1251 Methyl vinyl ketone, stabilized

UN1259 Nickel carbonyl

UN1261 Nitromethane

UN1262 Octanes

UN1263 Paint including paint, lacquer, enamel, stain, shellac solutions, varnish, polish, liquid filler, and liquid

lacquer base, or Paint related material including paint thinning, drying, removing, or reducing

compound

UN1264 Paraldehyde

UN1265 Pentanes

UN1266 Perfumery products with flammable solvents

UN1267 Petroleum crude oil

UN1268 Petroleum distillates, n.o.s. or Petroleum products, n.o.s.

NA1270 Petroleum oil

UN1272 Pine oil

UN1274 n–Propanol or Propyl alcohol, normal

UN1275 Propionaldehyde

UN1276 n–Propyl acetate

UN1277 Propylamine

UN1278 1-Chloropropane

UN1279 1,2–Dichloropropane

UN1280 Propylene oxide

UN1281 Propyl formates

UN1282 Pyridine

UN1286 Rosin oil

UN1287 Rubber solution

UN1288 Shale Oil

UN1289 Sodium methylate solutions in alcohol

UN1292 Tetraethyl silicate

UN1293 Tinctures, medicinal

UN1294 Toluene

UN1295 Trichlorosilane

UN1296 Triethylamine

UN1297 Trimethylamine, aqueous solutions with not more than 50 percent trimethylamine by mass

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 299

UN1298 Trimethylchlorosilane

UN1299 Turpentine

UN1300 Turpentine substitute

UN1301 Vinyl acetate, stabilized

UN1302 Vinyl ethyl ether, stabilized

UN1303 Vinylidene chloride, stabilized

UN1304 Vinyl isobutyl ether, stabilized

UN1305 Vinyltrichlorosilane, stabilized

UN1306 Wood preservatives, liquid

UN1307 Xylenes

UN1308 Zirconium suspended in a liquid

UN1309 Aluminum powder, coated

UN1310 Ammonium picrate, wetted with not less than 10 percent water, by mass

UN1312 Borneol

UN1313 Calcium resinate

UN1314 Calcium resinate, fused

UN1318 Cobalt resinate, precipitated

UN1320 Dinitrophenol, wetted with not less than 15 percent water, by mass

UN1321 Dinitrophenolates, wetted with not less than 15 percent water, by mass

UN1322 Dinitroresorcinol, wetted with not less than 15 percent water, by mass

UN1323 Ferrocerium

UN1324 Films, nitrocellulose base, gelatine coated (except scrap)

NA1325 Fusee (railway or highway) or Medicines, flammable, solid, n.o.s.

UN1325 Flammable solids, organic, n.o.s.

UN1326 Hafnium powder, wetted with not less than 25 percent water (a visible excess of water must be

present) (a) mechanically produced, particle size less than 53 microns; (b) chemically produced,

particle size less than 840 microns

UN1328 Hexamethylenetetramine

UN1330 Manganese resinate

UN1331 Matches, strike anywhere

UN1332 Metaldehyde

UN1333 Cerium, slabs, ingots, or rods

UN1334 Naphthalene, crude or Naphthalene, refined

UN1336 Nitroguanidine, wetted or Picrite, wetted with not less than 20 percent water, by mass

UN1337 Nitrostarch, wetted with not less than 20 percent water, by mass

UN1338 Phosphorus, amorphous

UN1339 Phosphorus heptasulfide, free from yellow or white phosphorus

UN1340 Phosphorus pentasulfide, free from yellow or white phosphorus

UN1341 Phosphorus sesquisulfide, free from yellow or white phosphorus

UN1343 Phosphorus trisulfide, free from yellow or white phosphorus

NA1344 Picric acid, wet, with not less than 10 percent water

UN1344 Trinitrophenol, wetted with not less than 30 percent water, by mass

UN1346 Silicon powder, amorphous

UN1347 Silver picrate, wetted with not less than 30 percent water, by mass

UN1348 Sodium dinitro–o–cresolate, wetted with not less than 15 percent water, by mass

UN1349 Sodium picramate, wetted with not less than 20 percent water, by mass

Appendix B Hazardous, Restricted, and Perishable Mail

300 Publication 52

NA1350 Sulfur

UN1350 Sulfur

UN1352 Titanium powder, wetted with not less than 25 percent water (a visible excess of water must be

present) (a) mechanically produced, particle size less than 53 microns; (b) chemically produced,

particle size less than 840 microns

UN1353 Fibers or Fabrics impregnated with weakly nitrated nitrocellulose, n.o.s.

UN1355 Trinitrobenzoic acid, wetted with not less than 30 percent water, by mass

UN1356 Trinitrotoluene wetted with not less than 30 percent water, by mass

UN1357 Urea nitrate, wetted with not less than 20 percent water, by mass

UN1358 Zirconium powder, wetted with not less than 25 percent water (a visible excess of water must be

present) (a) mechanically produced, particle size less than 53 microns; (b) chemically produced,

particle size less than 840 microns

UN1360 Calcium phosphide

NA1361 Charcoal briquettes, shell, screenings, wood, etc.

UN1361 Carbon, animal or vegetable origin

UN1362 Carbon, activated

UN1363 Copra

UN1364 Cotton waste, oily

NA1365 Cotton

UN1365 Cotton, wet

UN1369 p–Nitrosodimethylaniline

UN1372 Fibers, animal or Fibers, vegetable burnt, wet or damp

UN1373 Fibers or Fabrics, animal or vegetable or Synthetic, n.o.s. with animal or vegetable oil

UN1374 Fish meal, unstabilized or Fish scrap, unstabilized

UN1376 Iron oxide, spent, or Iron sponge, spent obtained from coal gas purification

UN1378 Metal catalyst, wetted with a visible excess of liquid

UN1379 Paper, unsaturated oil treated incompletely dried (including carbon paper)

UN1380 Pentaporane

UN1381 Phosphorus, white dry or Phosphorus, white, under water or Phosphorus white, in solution or

Phosphorus, yellow dry or Phosphorus, yellow, under water or Phosphorus, yellow, in solution

UN1382 Potassium sulfide, anhydrous or Potassium sulfide with less than 30 percent water of crystallization

UN1383 Pyrophoric metals, n.o.s. or Pyrophoric alloys, n.o.s.

UN1384 Sodium dithionite or Sodium hydrosulfite

UN1385 Sodium sulfide, anhydrous or Sodium sulfide with less than 30 percent water of crystallization

UN1386 Seed cake, containing vegetable oil solvent extractions and expelled seeds, with not more than 10

percent of oil and when the amount of moisture is higher than 11 percent, with not more than 20

percent of oil and moisture combined or Seed cake with more than 1.5 percent oil and not more than

11 percent moisture

UN1387 Wool waste, wet

UN1389 Alkali metal amalgam, liquid

UN1390 Alkali metal amides

UN1391 Alkali metal dispersions, or Alkaline earth metal dispersions

UN1392 Alkaline earth metal amalgams, liquid

UN1393 Alkaline earth metal alloys, n.o.s.

UN1394 Aluminum carbide

UN1395 Aluminum ferrosilicon powder

UN1396 Aluminum powder, uncoated

UN1397 Aluminum phosphide

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 301

UN1398 Aluminum silicon powder, uncoated

UN1400 Barium

UN1401 Calcium

UN1402 Calcium carbide

UN1403 Calcium cyanamide with more than 0.1 percent of calcium carbide

UN1404 Calcium hydride

UN1405 Calcium silicide

UN1407 Cesium or Caesium

UN1408 Ferrosilicon, with 30 percent or more but less than 90 percent silicon

UN1409 Metal hydrides, water–reactive, n.o.s.

UN1410 Lithium aluminum hydride

UN1411 Lithium aluminum hydride, ethereal

UN1413 Lithium borohydride

UN1414 Lithium hydride

UN1415 Lithium

UN1417 Lithium silicon

UN1418 Magnesium, powder or Magnesium alloys, powder

UN1419 Magnesium aluminum phosphide

UN1420 Potassium, metal alloys

UN1421 Alkali metal alloys, liquid, n.o.s.

UN1422 Potassium sodium alloys

UN1423 Rubidium

UN1426 Sodium borohydride

UN1427 Sodium hydride

UN1428 Sodium

UN1431 Sodium methylate

UN1432 Sodium phosphide

UN1433 Stannic phosphide

UN1435 Zinc ashes

UN1436 Zinc powder or Zinc dust

UN1437 Zirconium hydride

UN1438 Aluminum, nitrate

UN1439 Ammonium dichromate

UN1442 Ammonium perchlorate

UN1444 Ammonium persulfate

UN1445 Barium chlorate, solid

UN1446 Barium nitrate

UN1447 Barium perchlorate, solid

UN1448 Barium permanganate

UN1449 Barium peroxide

UN1450 Bromates, inorganic, n.o.s.

UN1451 Cesium nitrate or Caesium nitrate

UN1452 Calcium chlorate

UN1453 Calcium chlorite

UN1454 Calcium nitrate

UN1455 Calcium perchlorate

Appendix B Hazardous, Restricted, and Perishable Mail

302 Publication 52

UN1456 Calcium permanganate

UN1457 Calcium peroxide

UN1458 Chlorate and borate mixtures

UN1459 Chlorate and magnesium chloride mixture, solid

UN1461 Chlorates, inorganic, n.o.s.

UN1462 Chlorites, inorganic, n.o.s.

NA1463 Chromic acid, solid

UN1463 Chromium trioxide, anhydrous

UN1465 Didymium nitrate

UN1466 Ferric nitrate

UN1467 Guanidine nitrate

UN1469 Lead nitrate

UN1470 Lead perchlorate, solid or Lead perchlorate, solution

UN1471 Lithium hypochlorite, dry or Lithium hypochlorite mixtures, dry

UN1472 Lithium peroxide

UN1473 Magnesium bromate

UN1474 Magnesium nitrate

UN1475 Magnesium perchlorate

UN1476 Magnesium peroxide

UN1477 Nitrates, inorganic, n.o.s.

NA1479 Medicines, oxidizing substance, solid, n.o.s.

UN1479 Oxidizing solid, n.o.s.

UN1481 Perchlorates, inorganic, n.o.s.

UN1482 Permanganates, inorganic, n.o.s.

UN1483 Peroxides, inorganic, n.o.s.

UN1484 Potassium bromate

UN1485 Potassium chlorate

UN1486 Potassium nitrate

UN1487 Potassium nitrate and sodium nitrite mixtures

UN1488 Potassium nitrite

UN1489 Potassium perchlorate, solid or Potassium perchlorate, solution

UN1490 Potassium permanganate

UN1491 Potassium peroxide

UN1492 Potassium persulfate

UN1493 Silver nitrate

UN1494 Sodium bromate

UN1495 Sodium chlorate

UN1496 Sodium chlorite

UN1498 Sodium nitrate

UN1499 Sodium nitrate and potassium nitrate mixtures

UN1500 Sodium nitrite

UN1502 Sodium perchlorate

UN1503 Sodium permanganate

UN1504 Sodium peroxide

UN1505 Sodium persulfate

UN1506 Strontium chlorate

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 303

UN1507 Strontium nitrate

UN1508 Strontium perchlorate

UN1509 Strontium peroxide

UN1510 Tetranitromethane

UN1511 Urea hydrogen peroxide

UN1512 Zinc ammonium nitrite

UN1513 Zinc chlorate

UN1514 Zinc nitrate

UN1515 Zinc permanganate

UN1516 Zinc peroxide

UN1517 Zirconium picramate, wetted with not less than 20 percent water, by mass

UN1541 Acetone cyanohydrin, stabilized

UN1544 Alkaloids, solid, n.o.s. or Alkaloid salts, solid, n.o.s. poisonous

UN1545 Allyl isothiocyanate, stabilized

UN1546 Ammonium arsenate

UN1547 Aniline

UN1548 Aniline hydrochloride

NA1549 Antimony tribromide, solution or Antimony, trifluoride, solid or Antimony, trifluoride, solution or

Antimony tribromide, solid

UN1549 Antimony compounds, inorganic, solid, n.o.s.

UN1550 Antimony lactate

UN1551 Antimony potassium tartrate

UN1553 Arsenic acid, liquid

UN1554 Arsenic acid, solid

UN1555 Arsenic bromide

NA1556 Methyldichloroarsine

UN1556 Arsenic compounds, liquid, n.o.s. inorganic, including arsenates, n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic compounds of arsenic, n.o.s.

NA1557 Arsenic sulfide or Arsenic trisulfide

UN1557 Arsenic compounds, solid, n.o.s. inorganic, including arsenates, n.o.s.; arsenites, n.o.s.; arsenic

sulfides, n.o.s.; and organic compounds of arsenic, n.o.s.

UN1558 Arsenic

UN1559 Arsenic pentoxide

UN1560 Arsenic trichloride

UN1561 Arsenic trioxide

UN1562 Arsenical dust

UN1564 Barium compounds, n.o.s.

UN1565 Barium cyanide

UN1566 Beryllium compounds, n.o.s.

UN1567 Beryllium, powder

UN1569 Bromoacetone

UN1570 Brucine

UN1571 Barium azide, wetted with not less than 50 percent water, by mass

UN1572 Cacodylic acid

UN1573 Calcium arsenate

NA1574 Calcium arsenite, solid

Appendix B Hazardous, Restricted, and Perishable Mail

304 Publication 52

UN1574 Calcium arsenate and calcium arsenite, mixtures, solid

UN1575 Calcium cyanide

UN1577 Chlorodinitrobenzenes, liquid

UN1578 Chloronitrobenzene, solid

UN1579 4–Chloro–o–toluidine hydrochloride, solid

UN1580 Chloropicrin

UN1581 Chloropicrin and methyl bromide mixtures

UN1582 Chloropicrin and methyl chloride mixtures

UN1583 Chloropicrin mixtures, n.o.s.

UN1585 Copper acetoarsenite

UN1586 Copper arsenite

UN1587 Copper cyanide

UN1588 Cyanides, inorganic, solid, n.o.s.

UN1589 Cyanogen chloride, stabilized

UN1590 Dichloroanilines, liquid

UN1591 o–Dichlorobenzene

UN1593 Dichloromethane

UN1594 Diethyl sulfate

UN1595 Dimethyl sulfate

UN1596 Dinitroanilines

UN1597 Dinitrobenzenes, liquid

UN1598 Dintro–o–cresol

UN1599 Dinitrophenel solutions

UN1600 Dinitrotoluenes, molten

UN1601 Disinfectants, solid, toxic, n.o.s.

UN1602 Dyes, liquid, toxic, n.o.s. or Dye intermediates, liquid, toxic, n.o.s.

UN1603 Ethyl bromoacetate

UN1604 Ethylenediamine

UN1605 Ethylene dibromide

UN1606 Ferric arsenate

UN1607 Ferric arsenite

UN1608 Ferrous arsenate

UN1611 Hexaethyl tetraphosphate, liquid or Hexaethyl tetraphosphate, solid

UN1612 Hexaethyl tetraphosphate and compressed gas mixtures

UN1613 Hydrocyanic acid, aqueous solutions or Hydrogen cyanide, aqueous solutions with not more than 20

percent hydrogen cyanide or Hydrocyanic acid, aqueous solutions with less than 5 percent hydrogen

cyanide

UN1614 Hydrogen cyanide, stabilized with less than 3 percent water and absorbed in a porous inert material

UN1616 Lead acetate

UN1617 Lead arsenates

UN1618 Lead arsenites

UN1620 Lead cyanide

UN1621 London purple

UN1622 Magnesium arsenate

UN1623 Mercuric arsenate

UN1624 Mercuric chloride

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 305

UN1625 Mercuric nitrate

UN1626 Mercuric potassium cyanide

UN1627 Mercurous nitrate

UN1629 Mercury acetate

UN1630 Mercury ammonium chloride

UN1631 Mercury benzoate

UN1634 Mercury bromides

UN1636 Mercury cyanide

UN1637 Mercury gluconate

UN1638 Mercury iodide, solution or Mercury iodide, solid

UN1639 Mercury nucleate

UN1640 Mercury oleate

UN1641 Mercury oxide

UN1642 Mercury oxycyanide, desensitized

UN1643 Mercury potassium iodide

UN1644 Mercury salicylate

UN1645 Mercury sulfates

UN1646 Mercury thiocyanate

UN1647 Methyl bromide and ethylene dibromide mixtures, liquid

UN1648 Acetonitrile

UN1649 Motor fuel anti–knock mixtures

UN1650 beta–Naphthylamine

UN1651 Naphthylthiourea

UN1652 Naphthylurea

UN1653 Nickel cyanide

UN1654 Nicotine

UN1655 Nicotine compounds, solid, n.o.s. or Nicotine preparations, solid, n.o.s.

UN1656 Nicotine hydrochloride or Nicotine hydrochloride solution

UN1657 Nicotine salicylate

UN1658 Nicotine sulfate, solid or Nicotine sulfate, solution

UN1659 Nicotine tartrate

UN1660 Nitric oxide, compressed

UN1661 Nitroanilines (o–; m–; p–;)

UN1662 Nitrobenzene

UN1663 Nitophenols (o–; m–; p–;)

UN1664 Nitrotoluenes, liquid (o–; m–; p–;) or Nitrotoluenes, solid (m–; or p–;)

UN1665 Nitroxylenes (o–; m–; p–‘)

UN1669 Pentachloroethane

UN1670 Perchloromethyl mercaptan

UN1671 Phenol, solid

UN1672 Phenylcarbylamine chloride

UN1673 Phenylenediamines (o–; m–; p–;)

UN1674 Phenylmercuric acetate

UN1677 Potassium arsenate

UN1678 Potassium arsenite

UN1679 Potassium cuprocyanide

Appendix B Hazardous, Restricted, and Perishable Mail

306 Publication 52

UN1680 Potassium cyanide

UN1683 Silver arsenite

UN1684 Silver cyanide

UN1685 Sodium arsenate

UN1686 Sodium arsenite, aqueous solutions

UN1687 Sodium azide

UN1688 Sodium cacodylate

UN1689 Sodium cyanide

UN1690 Sodium fluoride

UN1691 Strontium arsenite

UN1692 Strychnine or Strychnine salts

NA1693 Tear gas devices with more than 2 percent tear gas substances, by mass

UN1693 Tear gas substances, liquid, n.o.s.

UN1694 Bromobenzyl cyanides, liquid

UN1695 Chloroacetone, stabilized

UN1697 Chloroacetophenone (CN), solid

UN1698 Diphenylamine chloroarsine

UN1699 Diphenylchloroarsine, liquid

UN1700 Tear gas candles

UN1701 Xylyl bromide, liquid

UN1702 1,1,2,-Tetrachloroethane

UN1704 Tetraethyl dithiopyrophosphate

UN1707 Thallium compounds, n.o.s.

UN1708 Toluidines liquid

UN1709 2,4–Toluylenediamine, solid or 2,4–Toluenediamine, solid

UN1710 Trichloroethylene

UN1711 Xylidines, liquid

UN1712 Zinc arsenate or Zinc arsenite or Zinc arsenate and zinc arsenite mixtures

UN1713 Zinc cyanide

UN1714 Zinc phosphide

UN1715 Acetic anhydride

UN1716 Acetyl bromide

UN1717 Acetyl chloride

UN1718 Butyl acid phosphate

UN1719 Caustic alkali liquids, n.o.s.

UN1722 Allyl chloroformate

UN1723 Allyl iodide

UN1724 Allyltrichlorosilane, stabilized

UN1725 Aluminum bromide, anhydrous

UN1726 Aluminum chloride, anhydrous

UN1727 Ammonium hydrogendifluoride, solid

UN1728 Amyltrichlorosilane

UN1729 Anisoyl chloride

UN1730 Antimony pentachloride, liquid

UN1731 Antimony pentachloride, solutions

UN1732 Antimony pentafluoride

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 307

UN1733 Antimony trichloride, liquid or Antimony trichloride, solid

UN1736 Benzoyl chloride

UN1737 Benzyl bromide

UN1738 Benzyl chloride or Benzyl chloride unstabilized

UN1739 Benzyl chloroformate

UN1740 Hydrogendifluorides, n.o.s. solid or Hydrogendifluorides, n.o.s. solutions

UN1741 Boron trichloride

UN1742 Boron trifluoride acetic acid complex, liquid

UN1743 Boron trifluoride propionic acid complex, liquid

UN1744 Bromine or Bromine solutions

UN1745 Bromine pentafluoride

UN1746 Bromine trifluoride

UN1747 Butyltrichlorosilane

UN1748 Calcium hypochlorite, dry or Calcium hypochlorite mixtures dry with more than 39 percent available

chlorine (8.8 percent available oxygen)

UN1749 Chlorine trifluoride

UN1750 Chloroacetic acid, solution

UN1751 Chloroacetic acid, solid

UN1752 Chloroacetyl chloride

UN1753 Chlorophenyltrichlorosilane

UN1754 Chlorosulfonic acid (with or without sulfur trioxide)

UN1755 Chromic acid solution

UN1756 Chromic fluoride, solid

UN1757 Chromic fluoride, solution

UN1758 Chromium oxychloride

NA1759 Ferrous chloride, solid

UN1759 Corrosive solids, n.o.s.

NA1760 Ferrous chloride, solution

UN1760 Corrosive liquids, n.o.s.

UN1761 Cupriethylenediamine solution

UN1762 Cyclohexenyltrichlorosilane

UN1763 Cyclohexyltrichlorosilane

UN1764 Dichloroacetic acid

UN1765 Dichloroacetyl chloride

UN1766 Dichlorophenyltrichlorosilane

UN1767 Diethyldichlorosilane

UN1768 Difluorophosphoric acid, anhydrous

UN1769 Diphenyldichlorosilane

UN1770 Diphenylmethyl bromide

UN1771 Dodecyltrichlorosilane

UN1773 Ferric chloride, anhydrous

UN1774 Fire extinguisher charges, corrosive liquid

UN1775 Fluoroboric acid

UN1776 Fluorophosphoric acid anhydrous

UN1777 Fluorosulfonic acid

UN1778 Fluorosilicic acid

Appendix B Hazardous, Restricted, and Perishable Mail

308 Publication 52

UN1779 Formic acid

UN1780 Fumaryl chloride

UN1781 Hexadecyltrichlorosilane

UN1782 Hexafluorophosphoric acid

UN1783 Hexamethylenediamine solution

UN1784 Hexyltrichlorosilane

UN1786 Hydrofluoric acid and Sulfuric acid mixtures

UN1787 Hydriodic acid

UN1788 Hydrobromic acid, with more than 49 percent hydrobromic acid or Hydrobromic acid, with not more

than 49 percent hydrobromic acid

UN1789 Hydrochloric acid

UN1790 Hydrofluoric acid, with more than 60 percent strength or Hydrofluoric acid, with not more than 60

percent strength

UN1791 Hypochlorite solutions

UN1792 Iodine monochloride

UN1793 Isopropyl acid phosphate

UN1794 Lead sulfate with more than 3 percent free acid

UN1796 Nitrating acid mixtures, with more than 50 percent nitric acid or Nitrating acid mixtures, with not more

than 50 percent nitric acid

UN1798 Nitrohydrochloric acid

UN1799 Nonyltrichlorosilane

UN1800 Octadecyltrichlorosilane

UN1801 Octyltrichlorosilane

UN1802 Perchloric acid with not more than 50 percent acid by mass

UN1803 Phenolsulfonic acid, liquid

UN1804 Phenyltrichlorosilane

UN1805 Phosphoric acid

UN1806 Phosphorus pentachloride

UN1807 Phosphorus pentoxide

UN1808 Phosphorus tribromide

UN1809 Phosphorus trichloride

UN1810 Phosphorus oxychloride

UN1811 Potassium hydrogendifluoride, solid or Potassium hydrogendifluoride, solution

UN1812 Potassium fluoride

UN1813 Potassium hydroxide, solid

UN1814 Potassium hydroxide, solution

UN1815 Propionyl chloride

UN1816 Propyltrichlorosilane

UN1817 Pyrosulfuryl chloride

UN1818 Silicon tetrachloride

UN1819 Sodium aluminate, solution

UN1823 Sodium hydroxide, solid

UN1824 Sodium hydroxide solution

UN1825 Sodium monoxide

UN1826 Nitrating acid mixtures, spent with more than 50 percent nitric acid or Nitrating acid mixtures, spent

with not more than 50 percent nitric acid

UN1827 Stannic chloride, anhydrous

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 309

UN1828 Sulfur chlorides

UN1829 Sulfur trioxide, inhibited or Sulfur trioxide, stabilized

UN1830 Sulfuric acid with more than 51 percent acid

UN1831 Sulfuric acid, fuming with 30 percent or more free sulfur trioxide or Sulfuric acid, fuming with less than

30 percent free sulfur trioxide

UN1832 Sulfuric acid, spent

UN1833 Sulfurous acid

UN1834 Sulfuryl chloride

UN1835 Tetramethylammonium hydroxide solution

UN1836 Thionyl chloride

UN1837 Thiophosphoryl chloride

UN1838 Titanium tetrachloride

UN1839 Trichloroacetic acid

UN1840 Zinc chloride, solution

UN1841 Acetaldehyde ammonia

UN1843 Ammonium dintro–o–cresolate, solid

UN1845 Carbon dioxide, solid, or Dry ice

UN1846 Carbon tetrachloride

UN1847 Potassium sulfide, hydrated with not less than 30 percent water of crystallization

UN1848 Propionic acid

UN1849 Sodium sulfide, hydrated with not less than 30 percent water

UN1851 Medicine, liquid, toxic, n.o.s.

UN1854 Barium alloys, pyrophic

UN1855 Calcium, pyrophoric or Calcium alloys, pyrophoric

UN1857 Textile waste, wet

UN1858 Hexafluoropropylene, compressed or Refrigerant gas R 1216

UN1859 Silicon tetrafluoride, compressed

UN1860 Vinyl fluoride, inhibited

UN1862 Ethyl crotonate

UN1863 Fuel, aviation, turbine engine

UN1865 n–Propyl nitrate

UN1866 Resin solution, flammable

UN1869 Magnesium or Magnesium alloys with more than 50 percent magnesium in pellets, turnings, or

ribbons

UN1870 Potassium borohydride

UN1871 Titanium hydride

UN1872 Lead dioxide

UN1873 Perchloric acid with more than 50 percent but not more than 72 percent acid, by mass

UN1884 Barium oxide

UN1885 Benzidine

UN1886 Benzylidene chloride

UN1887 Bromochloromethane

UN1888 Chloroform

UN1889 Cyanogen bromide

UN1891 Ethyl bromide

UN1892 Ethyldichloroarsine

Appendix B Hazardous, Restricted, and Perishable Mail

310 Publication 52

UN1894 Phenylmercuric hydroxide

UN1895 Phenylmercuric nitrate

UN1897 Tetrachloroethylene

UN1898 Acetyl iodide

UN1902 Diisooctyl acid phosphate

UN1903 Disinfectants, liquid, corrosive, n.o.s.

UN1905 Selenic acid

UN1906 Sludge, acid

UN1907 Soda lime with more than 4 percent sodium hydroxide

UN1908 Chlorite solution

UN1910 Calcium oxide

NA1911 Diborane mixtures

UN1911 Diborane

UN1912 Methyl chloride and methylene chloride mixtures

UN1913 Neon, refrigerated liquid (cryogenic liquid)

UN1914 Butyl propionates

UN1915 Cyclohexanone

UN1916 2,2’–Dichlorodiethyl ether

UN1917 Ethyl acrylate, stabilized

UN1918 Isopropylbenzene

UN1919 Methyl acrylate, inhibited

UN1920 Nonanes

UN1921 Propyleneimine, inhibited

UN1922 Pyrrolidine

UN1923 Calcium dithionite or Calcium hydrosulfite

UN1928 Methyl magnesium bromide, in ethyl ether

UN1929 Potassium dithionite or Potassium hydrosulfite

UN1931 Zinc dithionite or Zinc hydrosulfite

UN1932 Zirconium scrap

UN1935 Cyanide solutions, n.o.s.

UN1938 Bromoacetic acid, solution

UN1939 Phosphorus oxybromide

UN1940 Thioglycolic acid

UN1941 Dibromodifluoromethane, R12B2

UN1942 Ammonium nitrate, with not more than 0.2 percent of combustible substances, including any organic

substance calculated as carbon, to the exclusion of any other added substance

UN1944 Matches, safety (book, card, or strike on box)

UN1945 Matches, wax, Vesta

UN1950 Aerosols, corrosive, Packing Group II or III, (each not exceeding 1 L capacity) or Aerosols, flammable

(each not exceeding 1 L capacity) or Aerosols, flammable, n.o.s. (engine starting fluid) (each not

exceeding 1 L capacity) or Aerosols, nonflammable (each not exceeding 1 L capacity) or Aerosols,

poison, each not exceeding 1 L capacity

UN1951 Argon, refrigerated liquid (cryogenic liquid)

UN1952 Ethylene oxide and carbon dioxide mixtures with not more than 9 percent ethylene oxide

UN1953 Compressed gas, toxic, flammable, n.o.s. Inhalation Hazard Zone A, B, C, or D

NA1954 Insecticide gases flammable n.o.s. or Refrigerant gases, n.o.s., or Dispersant gases, n.o.s. or

Refrigerating machines, containing flammable, nonpoisonous, liquified gas

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 311

UN1954 Compressed gas, flammable, n.o.s.

NA1955 Organic phosphate, mixed with compressed gas or Organic phosphate compound, mixed with

compressed gas or Organic phosphorous compound, mixed with compressed gas

UN1955 Compressed gas, toxic, n.o.s. Inhalation Hazard Zone A, B, C, or D

NA1956 Accumulators, pressurized, pneumatic or hydraulic (containing nonflammable gas)

UN1956 Compressed gas, n.o.s.

UN1957 Deuterium, compressed

UN1958 1,2–Dichloro–1,1,2,2–Tetrafluoroethane or Refrigerant gas R 114

UN1959 1,1–Difluoroethylene or Refrigerant gas R 1132a

NA1961 Ethane–Propane mixture, refrigerated liquid

UN1961 Ethane, refrigerated liquid

UN1962 Ethylene

UN1963 Helium, refrigerated liquid (cyrogenic liquid)

UN1964 Hydrocarbon gas mixture, compressed, n.o.s.

UN1965 Hydrocarbon gas mixtures, liquified, n.o.s.

UN1966 Hydrogen, refrigerated liquid (cryogenic liquid)

NA1967 Parathion and compressed gas mixture

UN1967 Insecticide gases, toxic, n.o.s.

UN1968 Insecticide gases, n.o.s.

UN1969 Isobutane see also Petroleum gases, liquified

UN1970 Krypton, refrigerated liquid (cryogenic liquid)

UN1971 Methane, compressed or Natural gas, compressed (with high methane content)

UN1972 Methane, refrigerated liquid (cryogenic liquid) or Natural gas, refrigerated liquid (cryogenic liquid), with

high methane content

UN1973 Chlorodifluoromethane and chloropentafluoroethane mixture or Refrigerant gas R 502 with fixed

boiling point, with approximately 49 percent chlorodifluoromethane

UN1974 Chlorodifluorobromomethane or Refrigerant gas R 12B1

UN1975 Nitric oxide and dinitrogen tetroxide mixtures or Nitric oxide and nitrogen dioxide mixtures

UN1976 Octafluorocyclobutane, or Refrigerant gas RC 318

UN1977 Nitrogen, refrigerated liquid cryogenic liquid

UN1978 Propane see also Petroleum gases, liquified

UN1979 Rare gases, mixtures, compressed

UN1980 Rare gases and oxygen mixtures, compressed

UN1981 Rare gases and nitrogen mixtures, compressed

UN1982 Tetrafluoromethane, compressed or Refrigerant gas R 14

UN1983 1–Chloro–2,2,2–trifluoroethane or Refrigerant gas R 133a

UN1984 Trifluoromethane or Refrigerant gas R 23

UN1986 Alcohols, flammable, toxic, n.o.s.

NA1987 Denatured alcohol

UN1987 Alcohols, n.o.s.

UN1988 Aldehydes, flammable, toxic, n.o.s.

UN1989 Aldehydes, n.o.s.

UN1990 Benzaldehyde

UN1991 Chloroprene, stabilized

UN1992 Flammable liquids, toxic, n.o.s.

NA1993 Diesel fuel

Appendix B Hazardous, Restricted, and Perishable Mail

312 Publication 52

UN1993 Flammable liquids, n.o.s.

UN1994 Iron pentacarbonyl

NA1999 Asphalt, liquid including road oils and cutback, bitumens

UN1999 Tars, liquid including road asphalt and oils, bitumen and cut backs

UN2000 Celluloid, in block, rods, rolls, sheets, tubes, etc., except scrap

UN2001 Cobalt naphthenates, powder

UN2002 Celluloid, scrap

UN2003 Metal alkyls, water–reactive, n.o.s. or Metal aryls, water–reactive, n.o.s.

UN2004 Magnesium diamide

UN2005 Magnesium diphenyl

UN2006 Plastics, nitrocellulose–based, self–heating, n.o.s.

UN2008 Zirconium powder, dry

UN2009 Zirconium, dry, finished sheets, strip or coiled wire

UN2010 Magnesium hydride

UN2011 Magnesium phosphide

UN2012 Potassium phosphide

UN2013 Strontium phosphide

UN2014 Hydrogen peroxide, aqueous solutions with more than 40 percent but not more than 60 percent

hydrogen peroxide (stabilized as necessary) or Hydrogen peroxide, aqueous solutions with not less

than 20 percent but not more than 40 percent hydrogen peroxide (stabilized as necessary)

UN2015 Hydrogen peroxide, stabilized or Hydrogen peroxide aqueous solutions, stabilized with more than 60

percent hydrogen peroxide

UN2016 Ammunition, toxic, non–explosive, without burster or expelling charge, non–fuzed

UN2017 Ammunition, tear–producing, non–explosive, without burster or expelling charge, non–fuzed

UN2018 Chloroanilines, solid

UN2019 Chloroanilines, liquid

UN2020 Chlorophenols, solid

UN2021 Chlorophenols, liquid

UN2022 Cresylic acid

UN2023 Epichlorohydrin

UN2024 Mercury compounds, liquid, n.o.s.

UN2025 Mercury compounds, solid, n.o.s.

UN2026 Phenylmercuric compounds, n.o.s.

UN2027 Sodium arsenite, solid

UN2028 Bombs, smoke, non–explosive, with corrosive liquid, without initiating device

UN2029 Hydrazine, anhydrous or Hydrazine aqueous solutions with more than 64 percent hydrazine, by mass

UN2030 Hydrazine hydrate or Hydrazine aqueous solutions, with not less than 37 percent but not more than

64 percent hydrazine, by mass

UN2031 Nitric acid other than red fuming, with more than 70 percent nitric acid or Nitric acid other than red

fuming, with not more than 70 percent nitric acid

UN2032 Nitric acid, red fuming

UN2033 Potassium monoxide

UN2034 Hydrogen and Methane mixtures, compressed

UN2035 1,1,1–Trifluoroethane, compressed or Refrigerant gas R 143a

UN2036 Xenon, compressed

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 313

UN2037 Gas cartridges (flammable) without a release device, non–refillable or Receptacles, small, containing

gas (gas cartridges) flammable or nonflammable, without release device, not refillable and not

exceeding 1 L capacity

UN2038 Dinitrotoluenes, liquid

UN2044 2,2–Dimethylpropane

UN2045 Isobutyraldehyde or Isobutyl aldehyde

UN2046 Cymenes

UN2047 Dichloropropenes

UN2048 Dicyclopentadiene

UN2049 Diethylbenzene

UN2050 Diisobutylene, isomeric compounds

UN2051 2–Dimethylaminoethanol

UN2052 Dipentene

UN2053 Methyl isobutyl carbinol

UN2054 Morpholine

UN2055 Styrene monomer, inhibited

UN2056 Tetrahydrofuran

UN2057 Tripropylene

UN2058 Valeraldehyde

UN2059 Nitrocellulose, solution, flammable with not less than 12.6 percent nitrogen, by mass, and not more

than 55 percent nitrocellulose

UN2067 Ammonium nitrate based fertilizers

NA2069 Ammonium nitrate mixed fertilizers

UN2071 Ammonium nitrate based fertilizers

NA2072 Ammonium nitrate fertilizers

UN2073 Ammonia solution, relative density less than 0.880 at 15° C in water, with more than 35 percent but

not more than 50 percent ammonia

UN2074 Acrylamide, solid

UN2075 Chloral, anhydrous, inhibited

UN2076 Cresols, liquid

UN2077 alpha–Naphthylamine

UN2078 Toluene diisocyanate

UN2079 Diethylenetriamine

UN2186 Hydrogen chloride, refrigerated liquid

UN2187 Carbon dioxide, refrigerated liquid

UN2188 Arsine

UN2189 Dichlorosilane

UN2190 Oxygen difluoride, compressed

UN2191 Sulfuryl fluoride

UN2192 Germane

UN2193 Hexafluoroethane, compressed or Refrigerant gas R 116

UN2194 Selenium hexafluoride

UN2195 Tellurium hexafluoride

UN2196 Tungsten hexafluoride

UN2197 Hydrogen iodide, anhydrous

UN2198 Phosphorus pentafluoride, compressed

UN2199 Phosphine

Appendix B Hazardous, Restricted, and Perishable Mail

314 Publication 52

UN2200 Propadiene, inhibited

UN2201 Nitrous oxide, refrigerated liquid

UN2202 Hydrogen selenide, anhydrous

UN2203 Silane, compressed

UN2204 Carbonyl sulfide

UN2205 Adiponitrile

UN2206 Isocyanates, toxic, n.o.s. or Isocyanate solutions, toxic, n.o.s. flashpoint more than 61° C and boiling

point less than 300° C

UN2208 Calcium hypochlorite mixtures, dry, with more than 10 percent but not more than 39 percent available

chlorine

UN2209 Formaldehyde, solutions, with not less than 25 percent formaldehyde

UN2210 Maneb or Maneb preparations with not less than 60 percent maneb

UN2211 Polymeric beads, expandable, evolving flammable vapor

NA2212 Asbestos

UN2212 Blue asbestos (Crocidolite) or Brown asbestos (amosite, mysorite)

UN2213 Paraformaldehyde

UN2214 Phthalic anhydride with more than .05 percent maleic anhydride

NA2215 Maleic acid

UN2215 Maleic anhydride

UN2216 Fish meal, stabilized or Fish scrap, stabilized

UN2217 Seed cake with not more than 1.5 percent oil and not more than 11 percent moisture

UN2218 Acrylic acid, stabilized

UN2219 Allyl glycidyl ether

UN2222 Anisole

UN2224 Matches, fusee or Benzonitrile

UN2225 Benzene sulfonyl chloride

UN2226 Benzotrichloride

UN2227 n–Butyl methacrylate, stabilized

UN2232 2–Chloroethanal

UN2233 Chloroanisidines

UN2234 Chlorobenzotrifluorides

UN2235 Chlorobenzyl chlorides, liquid

UN2236 3–Chloro–4–methylphenyl isocyanate, liquid

UN2237 Chloronitroanilines

UN2238 Chlorotoluenes

UN2239 Chlorotoluidines, solid

UN2240 Chromosulfuric acid

UN2241 Cycloheptane

UN2242 Cycloheptene

UN2243 Cyclohexyl acetate

UN2244 Cyclopentanol

UN2245 Cyclopentanone

UN2246 Cyclopentene

UN2248 Di–n–butylamine

UN2249 Dichlorodimethyl ether, symmetrical

UN2250 Dichlorophenyl isocyanates

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 315

UN2251 Bicyclo [2,2,1] hepta–2, 5–diene, stabilized or 2,5–Norbornadiene, stabilized

UN2252 1,2–Dimethoxyethane

UN2253 N,N–Dimethylaniline

UN2254 Matches, fusee

UN2256 Cyclohexene

UN2257 Potassium

UN2258 1,2–Propylenediamine

UN2259 Triethylenetetramine

UN2260 Tripropylamine

UN2261 Xylenols, solid

UN2262 Dimethylcardamoyl chloride

UN2263 Dimethylcyclohexanes

UN2264 N,N-Dimethylcyclohexlamine

UN2265 N,N–Dimethylformamide

UN2266 Dimethyl–N–propylamine

UN2267 Dimethyl thiophosphoryl chloride

UN2269 3,3’–Iminodipropylamine

UN2270 Ethylamine, aqueous solution with not less than 50 percent but not more than 70 percent ethylamine

UN2271 Ethyl amyl ketone

UN2272 N–Ethylaniline

UN2273 2–Ethylaniline

UN2274 N–Ethyl–N–benzylaniline

UN2275 2–Ethylbutanol

UN2276 2–Ethylhexylamine

UN2277 Ethyl methacrylate, stabilized

UN2278 n–Heptane

UN2279 Hexachlorobutadiene

UN2280 Hexamethylenediamine, solid

UN2281 Hexamethylene diisocyanate

UN2282 Hexanols

UN2283 Isobutyl methacrylate, inhibited

UN2284 Isobutyronitrile

UN2285 Isocyanatobenzotrifluorides

UN2286 Pentamethylheptane

UN2287 Isoheptenes

UN2288 Isohexenes

UN2289 Isophoronediamine

UN2290 Isophorone diisocyanate

UN2291 Lead compounds, soluble, n.o.s.

UN2293 4–Methoxy–4–methylpentan–2–one

UN2294 N–Methylaniline

UN2295 Methyl chloroacetate

UN2296 Methylcyclohexane

UN2297 Methylcyclohexanone

UN2298 Methylcyclopentane

UN2299 Methyl dichloroacetate

Appendix B Hazardous, Restricted, and Perishable Mail

316 Publication 52

UN2300 2–Methyl–5–ethylpyridine

UN2301 2–Methylfuran

UN2302 5–Methylhexan–2–one

UN2303 Isopropenylbenzene

UN2304 Naphthalene, molten

UN2305 Nitrobenzenesulfonic acid

UN2306 Nitrobenzotrifluorides

UN2307 3–Nitro–4–chlorobenzotrifluoride

UN2308 Nitrosylsulfuric acid

UN2309 Octadiene

UN2310 Pentane–2,4–dione

UN2311 Phenetidines

UN2312 Phenol, molten

UN2313 Picolines

UN2315 Polychlorinated biphenyls, liquid or solid

UN2316 Sodium cuprocyanide, solid

UN2317 Sodium cuprocyanide, solution

UN2318 Sodium hydrosulfide, with less than 25 percent water of crystallization

UN2319 Terpene hydrocarbons, n.o.s.

UN2320 Tetraethylenepentamine

UN2321 Trichlorbenzenes, liquid

UN2322 Trichlorobutene

UN2323 Triethyl phosphite

UN2324 Triisobutylene

UN2325 1,3,5–Trimethylbenzene

UN2326 Trimethylcyclohexylamine

UN2327 Trimethylhexamethylenediamines

UN2328 Trimethylhexamethylene diisocyanate

UN2329 Trimethyl phosphite

UN2330 Undecane

UN2331 Zinc chloride, anhydrous

UN2332 Acetaldehyde oxime

UN2333 Allyl acetate

UN2334 Allylamine

UN2335 Allyl ethyl ether

UN2336 Allyl formate

UN2337 Phenyl mercaptan

UN2338 Benzotrifluoride

UN2339 2–Bromobutane

UN2340 2–Bromoethyl ethyl ether

UN2341 1–Bromo–3–methylbutane

UN2342 Bromomethylpropanes

UN2343 2–Bromopentane

UN2344 Bromopropanes

UN2345 3–Bromopropyne

UN2346 Butanedione

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 317

UN2347 Butyl mercaptans

UN2348 Butyl acrylates, stabilized

UN2350 Butyl methyl ether

UN2351 Butyl nitrites

UN2352 Butyl vinyl ether, stabilized

UN2353 Butyryl chloride

UN2354 Chloromethyl ethyl ether

UN2356 2–Chloropropane

UN2357 Cyclohexylamine

UN2358 Cyclooctatetraene

UN2359 Diallylamine

UN2360 Diallylether

UN2361 Diisobutylamine

UN2362 1,1–Dichloroethane

UN2363 Ethyl mercaptan

UN2364 n–Propyl benzene

UN2366 Diethyl carbonate

UN2367 alpha–Methylvaleraldehyde

UN2368 alpha–Pinene

UN2370 1–Hexene

UN2371 Isopentenes

UN2372 1,2–Di–(dimethylamino)ethane

UN2373 Diethoxymethane

UN2374 3,3–Diethoxypropene

UN2375 Diethyl sulfide

UN2376 2,3–Dihydropyran

UN2377 1,1–Dimethoxyethane

UN2378 N–Butylaniline or 2–Dimethylaminoacetonitrile

UN2379 1,3–Dimethylbutylamine

UN2380 Dimethyldiethoxysilane

UN2381 Dimethyl disulfide

UN2382 Dimethylhydrazine, symmetrical

UN2383 Dipropylamine

UN2384 Di–n–propyl ether

UN2385 Ethyl isobutyrate

UN2386 1–Ethylpiperidine

UN2387 Fluorobenzene

UN2388 Fluorotoluenes

UN2389 Furan

UN2390 2–Iodobutane

UN2391 Iodomethylpropanes

UN2392 Iodopropanes

UN2393 Isobutyl formate

UN2394 Isobutyl propionate

UN2395 Isobutyryl chloride

UN2396 Methacrylaldehyde, inhibited

Appendix B Hazardous, Restricted, and Perishable Mail

318 Publication 52

UN2397 3–Methylbutan–2–one

UN2398 Methyl tert–butyl ether

UN2399 1–Methylpiperidine

UN2400 Methyl isovalerate

UN2401 Piperidine

UN2402 Propanethiols

UN2403 Isopropenyl acetate

UN2404 Propionitrile

UN2405 Isopropyl butyrate

UN2406 Isopropyl isobutyrate

UN2407 Isopropyl chloroformate

UN2409 Isopropyl propionate

UN2410 1,2,3,6–Tetrahydropyridine

UN2411 Butyronitrile

UN2412 Tetrahydrothiophene

UN2413 Tetrapropylorthotitanate

UN2414 Thiophene

UN2416 Trimethyl borate

UN2417 Carbonyl fluoride

UN2418 Sulfur tetrafluoride

UN2419 Bromotrifluoroethylene

UN2420 Hexafluoroacetone

UN2421 Nitrogen trioxide

UN2422 Octafluorobut–2–ene or Refrigerant gas R 1318

UN2424 Octafluoropropane or Refrigerant gas R 218

UN2426 Ammonium nitrate, liquid (hot concentrated solution)

UN2427 Potassium chlorate, aqueous solution

UN2428 Sodium chlorate, aqueous solution

UN2429 Calcium chlorate aqueous solution

UN2430 Alkylphenols, solid, n.o.s. (including C2–C12 homologues)

UN2431 Anisidines

UN2432 N,N–Diethylaniline

UN2433 Chloronitrotoluenes, liquid

UN2434 Dibenzyldichlorosilane

UN2435 Ethylphenyldichlorosilane

UN2436 Thioacetic acid

UN2437 Methylphenyldichlorosilane

UN2438 Trimethylacetyl chloride

UN2439 Sodium hydrogendifluoride, solid or Sodium hydrogendifluoride, solution

UN2440 Stannic chloride, pentahydrate

UN2441 Titanium trichloride, pryophoric or Titanium trichloride mixtures, pyrophoric

UN2442 Trichloroacetyl chloride

UN2443 Vanadium oxytrichloride

UN2444 Vanadium tetrachloride

UN2445 Lithium alkyls

UN2446 Nitrocresols

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 319

UN2447 Phosphorus white, molten

NA2448 Sulfur, molten

UN2448 Sulfur, molten

UN2451 Nitrogen trifluoride, compressed

UN2452 Ethylacetylene, stabilized

UN2453 Ethyl fluoride or Refrigerant gas R 161

UN2454 Methyl fluoride, or Refrigerant gas R 41

UN2456 2–Chloropropene

UN2457 2,3–Dimethylbutane

UN2458 Hexadienes

UN2459 2–Methyl–1–butene

UN2460 2–Methyl–2–butene

UN2461 Methylpentadienes

UN2463 Aluminum hydride

UN2464 Beryllium nitrate

UN2465 Dichloroisocyanuric acid, dry or Dichloroisocyanuric acid salts

UN2466 Potassium superoxide

UN2468 Trichloroisocyanuric acid, dry

UN2469 Zinc bromate

UN2470 Phenylacetonitrile, liquid

UN2471 Osmium tetroxide

UN2473 Sodium arsanilate

UN2474 Thiophosgene

UN2475 Vanadium trichloride

UN2477 Methyl isothiocyanate

UN2478 Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flashpoint less

than 23° C

UN2480 Methyl isocyanate

UN2481 Ethyl isocyanate

UN2482 n–Propyl isocyanate

UN2483 Isopropyl isocyanate

UN2484 tert–Butyl isocyanate

UN2485 n–Butyl isocyanate

UN2486 Isobutyl isocyanate

UN2487 Phenyl isocyanate

UN2488 Cyclohexyl isocyanate

UN2490 Dichlorodisopropyl ether

UN2491 Ethanolamine or Ethanolamine solutions

UN2493 Hexamethyleneimine

UN2495 Iodine pentafluoride

UN2496 Propionic anhydride

UN2498 1,2,3,6–Tetrahydrobenzaldehyde

UN2501 Tris–(1–aziridinyl)phosphine oxide, solution

UN2502 Valeryl chloride

UN2503 Zirconium tetrachloride

UN2504 Tetrabromoethane

Appendix B Hazardous, Restricted, and Perishable Mail

320 Publication 52

UN2505 Ammonium fluoride

UN2506 Ammonium hydrogen sulfate

UN2507 Chloroplatinic acid, solid

UN2508 Molybdenum pentachloride

UN2509 Potassium hydrogen sulfate

UN2511 2–Chloropropionic acid

UN2512 Aminophenols (o–; m–; p–)

UN2513 Bromoacetyl bromide

UN2514 Bromobenzene

UN2515 Bromoform

UN2516 Carbon tetrabromide

UN2517 1–Chloro–1,1–difluoroethane or Refrigerant gas R 142b

UN2518 1,5,9–Cyclododecatriene

UN2520 Cyclooctadienes

UN2521 Diketene, stabilized

UN2522 2–Dimethylaminoethyl methacrylate

UN2524 Ethyl orthoformate

UN2525 Ethyl oxalate

UN2526 Furfurylamine

UN2527 Isobutyl acrylate, inhibited

UN2528 Isobutyl isobutyrate

UN2529 Isobutyric acid

UN2530 Isobutyric anhydride

UN2531 Methacrylic acid, inhibited

UN2533 Methyl trichloroacetate

UN2534 Methylchlorosilane

UN2535 4–Methylmorpholine or n–methylmorpholine

UN2536 Methyltetrahydrofuran

UN2538 Nitronaphthalene

UN2541 Terpinolene

UN2542 Tributylamine

UN2545 Hafnium powder, dry

UN2546 Titanium powder, dry

UN2547 Sodium superoxide

UN2548 Chlorine pentafluoride

UN2552 Hexafluoroacetone hydrate

UN2554 Methyl allyl chloride

UN2555 Nitrocellulose with water with not less than 25 percent water, by mass

UN2556 Nitrocellulose, with alcohol with not less than 25 percent alcohol, by mass, and with not more than

12.6 percent nitrogen, by dry mass

UN2557 Nitrocellulose, with not more than 12.6 percent nitrogen, by dry mass, or Nitrocellulose mixture with

pigment or Nitrocellulose mixture with plasticizer or Nitrocellulose mixture with pigment and

plasticizer

UN2558 Epibromohydrin

UN2560 2–Methylpentan–2–ol

UN2561 3–Methyl–1–butene

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 321

UN2564 Trichloroacetic acid, solution

UN2565 Dicyclohexylamine

UN2567 Sodium pentachlorophenate

UN2570 Cadmium compounds

UN2571 Alkylsulfuric acids

UN2572 Phenylhydrazine

UN2573 Thallium chlorate

UN2574 Tricresyl phosphate with more than 3 percent ortho isomer

UN2576 Phosphorus oxybromide, molten

UN2577 Phenylacetyl chloride

UN2578 Phosphorus trioxide

UN2579 Piperazine

UN2580 Aluminum bromide, solution

UN2581 Aluminum chloride, solution

UN2582 Ferric chloride, solution

UN2583 Alkyl sulfonic acids, solid or Aryl sulfonic acids, solid with more than 5 percent free sulfuric acid

UN2584 Alkyl sulfonic acids, liquid or Aryl sulfonic acids, liquid with more than 5 percent free sulfuric acid

UN2585 Alkyl sulfonic acids, solid or Aryl sulfonic acids, solid with not more than 5 percent free sulfuric acid

UN2586 Alkyl sulfonic acids, liquid or Aryl sulfonic acids, liquid with not more than 5 percent free sulfuric acid

UN2587 Benzoquinone

UN2588 Pesticides, solid, toxic, n.o.s.

UN2589 Vinyl chloroacetate

UN2590 White asbestos (chrysotile, actinolite, anthophyllite, tremolite)

UN2591 Xenon, refrigerated liquid (cryogenic liquids)

UN2599 Chlorotrifluoromethane and trifluoromethane azeotropic mixture or Refrigerant gas R 503 with

approximately 60 percent chlorotrifluoromethane

UN2601 Cyclobutane

UN2602 Dichlorodifluoromethane and difluoroethane azeotropic mixture or Refrigerant gas R 500 with

approximately 74 percent dichlorodifluoromethane

UN2603 Cycloheptatriene

UN2604 Boron trifluoride diethyl etherate

UN2605 Methoxymethyl isocyanate

UN2606 Methyl orthosilicate

UN2607 Acrolein dimer, stabilized

UN2608 Nitropropanes

UN2609 Triallyl borate

UN2610 Triallylamine

UN2611 Propylene chlorohydrin

UN2612 Methyl propyl ether

UN2614 Methallyl alcohol

UN2615 Ethyl propyl ether

UN2616 Triisopropyl borate

UN2617 Methylcyclohexanols, flammable

UN2618 Vinyltoluenes, stabilized

UN2619 Benzyldimethylamine

UN2620 Amyl butyrates

Appendix B Hazardous, Restricted, and Perishable Mail

322 Publication 52

UN2621 Acetyl methyl carbinol

UN2622 Glycidaldehyde

UN2623 Firelighters, solid with flammable liquid

UN2624 Magnesium silicide

UN2626 Chloric acid aqueous solution, with not more than 10 percent chloric acid

UN2627 Nitrites, inorganic, n.o.s.

UN2628 Potassium fluoroacetate

UN2629 Sodium fluoroacetate

NA2630 Sodium selenite

UN2630 Selenates or Selenites

UN2642 Fluoroacetic acid

UN2643 Methyl bromoacetate

UN2644 Methyl iodide

UN2645 Phenacyl bromide

UN2646 Hexachlorocyclopentadiene

UN2647 Malononitrile

UN2648 1,2–Dibromobutan–3–one

UN2649 1,3–Dichloroacetone

UN2650 1,1–Dichloro–1–nitroethane

UN2651 4,4’–Diaminodiphenyl methane

UN2653 Benzyl iodide

UN2655 Potassium fluorosilicate

UN2656 Quinoline

UN2657 Selenium disulfide

UN2659 Sodium chloroacetate

UN2660 Nitrotoluidines (mono)

UN2661 Hexachloroacetone

UN2662 Hydroquinone

UN2664 Dibromomethane

UN2667 Butyltoluenes

UN2668 Chloroacetonitrile

UN2669 Chlorocresols, solution

UN2670 Cyanuric chloride

UN2671 Aminopyridines (o–; m–; p–)

UN2672 Ammonia solution, relative density between 0.880 and 0.957 at 15° C in water, with more than 10

percent but not more than 35 percent ammonia

UN2673 2–Amino–4–chlorophenol

UN2674 Sodium fluorosilicate

UN2676 Stibine

UN2677 Rubidium hydroxide solution

UN2678 Rubidium hydroxide

UN2679 Lithium hydroxide, solution

UN2680 Lithium hydroxide, monohydrate or Lithium hydroxide, solid

UN2681 Caesium hydroxide solution

UN2682 Caesium hydroxide

UN2683 Ammonium sulfide solution

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 323

UN2684 Diethylaminopropylamine

UN2685 N,N–Diethylethylenediamine

UN2686 2–Diethylaminoethanol

UN2687 Dicyclohexylammonium nitrate

UN2688 1–Bromo–3–chloropropane

UN2689 Glycerol alpha–monochlorohydrin

UN2690 N–n–Butyl imidazole

UN2691 Phosphorus pentabromide

UN2692 Boron tribromide

UN2693 Bisulfites, aqueous solutions, n.o.s.

UN2698 Tetrahydrophthalic anhydrides with more than 0.05 percent of maleic anhydride

UN2699 Trifluoroacetic acid

UN2705 1–Pentol

UN2707 Dimethyldioxanes

UN2709 Butyl benzenes

UN2710 Dipropyl ketone

UN2713 Acridine

UN2714 Zinc resinate

UN2715 Aluminum resinate

UN2716 1,4–Butynediol

UN2717 Camphor, synthetic

UN2719 Barium bromate

UN2720 Chromium nitrate

UN2721 Copper chlorate

UN2722 Lithium nitrate

UN2723 Magnesium chlorate

UN2724 Manganese nitrate

UN2725 Nickel nitrate

UN2726 Nickel nitrite

UN2727 Thallium nitrate

UN2728 Zirconium nitrate

UN2729 Hexachlorobenzene

UN2730 Nitroanisole

UN2732 Nitrobromobenzenes liquid or Nitrobromobenzenes solid

UN2733 Amine, flammable, corrosive, n.o.s. or Polyamines, flammable, corrosive, n.o.s.

UN2734 Amine, liquid, corrosive, flammable, n.o.s. or Polyamines, liquid, corrosive, flammable, n.o.s.

UN2735 Amines, liquid, corrosive, n.o.s. or Polyamines, liquid, corrosive, n.o.s.

UN2739 Butyric anhydride

UN2740 n–Propyl chloroformate

UN2741 Barium hypochlorite with more than 22 percent available chlorine

NA2742 sec–Butyl chloroformate or Isobutyl chloroformate

UN2742 Chloroformates, toxic, corrosive, flammable, n.o.s.

UN2743 n–Butyl chloroformate

UN2744 Cyclobutyl chloroformate

UN2745 Chloromethyl chloroformate

UN2746 Phenyl chloroformate

Appendix B Hazardous, Restricted, and Perishable Mail

324 Publication 52

UN2747 tert–Butylcyclohexylchloroformate

UN2748 2–Ethylhexyl chloroformate

UN2749 Tetramethylsilane

UN2750 1,3–Dichloropropanol–2

UN2751 Diethylthiophosphoryl chloride

UN2752 1,2–Epoxy–3–ethoxypropane

UN2753 N–Ethylbenzyltoluidines liquid

UN2754 N–Ethyltoluidines

UN2757 Carbamate pesticides, solid, toxic

UN2758 Carbamate pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2759 Arsenical pesticides, solid, toxic

UN2760 Arsenical pesticides, liquid, flammable, toxic, flashpoint less than 23° C

NA2761 Aldrin, solid or Dieldrin

UN2761 Organochlorine pesticides, solid, toxic

NA2762 Aldrin, liquid

UN2762 Organochlorine pesticides liquid, flammable, toxic, flashpoint less than 23° C

UN2763 Triazine pesticides, solid, toxic

UN2764 Triazine pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2771 Thiocarbamate pesticides, solid, toxic

UN2772 Thiocarbamate pesticide, liquid, flammable, toxic, flashpoint less than 23° C

UN2775 Copper based pesticides, solid, toxic

UN2776 Copper based pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2777 Mercury based pesticides, solid, toxic

UN2778 Mercury based pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2779 Substituted nitrophenol pesticides, solid, toxic

UN2780 Substituted nitrophenol pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2781 Bipyridilium pesticides, solid, toxic

UN2782 Bipyridilium pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2783 Organophosphorus pesticides, solid, toxic

UN2784 Organophosphorus pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2785 4–Thiapentanal

UN2786 Organotin pesticides, solid, toxic

UN2787 Organotin pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN2788 Organotin compounds, liquid, n.o.s.

UN2789 Acetic acid, glacial or Acetic acid solution, with more than 80 percent acid, by mass

UN2790 Acetic acid solution, not less than 50 percent but not more than 80 percent acid, by mass or Acetic

acid solution, with more than 10 percent and less than 50 percent acid, by mass

UN2793 Ferrous metal borings or Ferrous metal shavings or Ferrous metal turnings or Ferrous metal cuttings

in a form liable to self–heating

UN2794 Batteries, wet, filled with acid, electric storage

UN2795 Batteries, wet, filled with alkali, electric storage

UN2796 Sulfuric acid with not more than 51 percent acid or Battery fluid, acid

UN2797 Battery fluid, alkali

UN2798 Phenyl phosphorus dichloride

UN2799 Phenyl phosphorus thiodichloride

UN2800 Batteries, wet, non–spillable, electric storage

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 325

UN2801 Dyes, liquid, corrosive, n.o.s. or Dye intermediates, liquid, corrosive, n.o.s.

UN2802 Copper chloride

UN2803 Gallium

UN2805 Lithium hydride, fused solid

UN2806 Lithium nitride

UN2809 Mercury or Mercury contained in manufactured articles

UN2810 Toxic, liquids, organic, n.o.s.

NA2811 Selenium oxide

UN2811 Toxic solids, organic, n.o.s.

UN2812 Sodium aluminate, solid

UN2813 Water–reactive solid, n.o.s.

UN2814 Infectious substances, affecting humans only

UN2815 N–Aminoethylpiperazine

UN2817 Ammonium hydrogendiflouride, solution

UN2818 Ammonium polysulfide, solution

UN2819 Amyl acid phosphate

UN2820 Butyric acid

UN2821 Phenol solutions

UN2822 2–Chloropyridine

UN2823 Crotonic acid, solid

UN2826 Ethyl chlorothioformate

UN2829 Caproic acid

UN2830 Lithium ferrosilicon

UN2831 1,1,1–Trichloroethane

UN2834 Phosphorous acid

UN2835 Sodium aluminum hydride

UN2837 Bisulfate, aqueous solution

UN2838 Vinyl butyrate, stabilized

UN2839 Aldol

UN2840 Butyraldoxime

UN2841 Di–n–amylamine

UN2842 Nitroethane

UN2844 Calcium manganese silicon

NA2845 Ethyl phosphonous dichloride, anhydrous pyrophoric liquid

UN2845 Pyrophoric liquids, organic, n.o.s.

UN2846 Pyrophoric solids, organic, n.o.s.

UN2849 3–Chloropropanol–1

UN2850 Propylene tetramer

UN2851 Boron trifluoride dihydrate

UN2852 Dipicryl sulfide, wetted with not less than 10 percent water, by mass

UN2853 Magnesium fluorosilicate

UN2854 Ammonium fluorosilicate

UN2855 Zinc fluorosilicate

UN2856 Fluorosilicates, n.o.s.

UN2857 Refrigerating machines, containing nonflammable, nontoxic, liquified gas or ammonia solution

(UN2672)

Appendix B Hazardous, Restricted, and Perishable Mail

326 Publication 52

UN2858 Zirconium, dry, coiled wire, finished metal sheets, strip (thinner than 254 microns but not thinner than

18 microns)

UN2859 Ammonium metavanadate

UN2861 Ammonium polyvanadate

UN2862 Vanadium pentoxide, nonfused form

UN2863 Sodium ammonium vanadate

UN2864 Potassium metavanadate

UN2865 Hydroxylamine sulfate

UN2869 Titanium trichloride mixtures

UN2870 Aluminum borohydride or Aluminum borohydride in devices

UN2871 Antimony powder

UN2872 Dibromochloropropane

UN2873 Dibutylaminoethanol

UN2874 Furfuryl alcohol

UN2875 Hexachlorophene

UN2876 Resorcinol

UN2878 Titanium sponge granules or Titanium sponge powders

UN2879 Selenium oxychloride

UN2880 Calcium hypochlorite, hydrated or Calcium hypochlorite, hydrated mixtures, with not less than 5.5

percent but not more than 16 percent water

UN2881 Metal catalyst, dry

UN2900 Infectious substances, affecting animals only

UN2901 Bromine chloride

UN2902 Pesticides, liquid, toxic, n.o.s.

UN2903 Pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN2904 Chlorophenolates, liquid or Phenolates, liquid

UN2905 Chlorophenolates, solid or Phenolates, solid

UN2907 Isosorbide dinitrate mixture with not less than 60 percent lactose, mannose, starch or calcium

hydrogen phosphate

UN2909 Radioactive material, excepted package–articles manufactured from natural uranium or depleted

uranium or natural thorium

UN2910 Radioactive material, excepted package–articles manufactured from natural or depleted uranium or

natural thorium or Radioactive material, excepted package–empty package or empty packaging or

Radioactive material, excepted package–instruments or articles or Radioactive material, excepted

package–limited quantity of material

UN2911 Radioactive material, excepted package–instruments or articles

UN2912 Radioactive material, low specific activity, n.o.s. or Radioactive material, LSA, n.o.s.

UN2913 Radioactive material, surface contaminated object or Radioactive material, SCO

UN2918 Radioactive material, fissile, n.o.s.

NA2920 Dichlorobutene

UN2920 Corrosive liquids, flammable, n.o.s.

UN2921 Corrosive solids, flammable, n.o.s.

NA2922 Sodium hydrosulfide, solution

UN2922 Corrosive liquids, toxic, n.o.s.

UN2923 Corrosive solids, toxic, n.o.s.

UN2924 Flammable liquids, corrosive, n.o.s.

UN2925 Flammable solids, corrosive, organic, n.o.s.

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 327

UN2926 Flammable solids, toxic, organic, n.o.s.

NA2927 Ethyl phosphonothioic dichloride, anhydrous or Ethyl phosphorodichloridate

UN2927 Toxic liquids, corrosive, organic, n.o.s.

UN2928 Toxic solids, corrosive, organic, n.o.s.

UN2929 Toxic liquids, flammable, organic, n.o.s.

UN2930 Toxic solids, flammable, organic, n.o.s.

UN2931 Vanadyl sulfate

UN2933 Methyl 2–chloropropionate

UN2934 Isopropyl 2–chloropropionate

UN2935 Ethyl 2–chloropropionate

UN2936 Thiolactic acid

UN2937 alpha–Methylbenzyl alcohol

UN2940 9–Phosphabicyclonoanes or Cyclooctadiene phosphines

UN2941 Fluoroanilines

UN2942 2–Trifluoromethylaniline

UN2943 Tetrahydrofurfurylamine

UN2945 N–Methylbutylamine

UN2946 2–Amino–5–diethylaminopentane

UN2947 Isopropyl chloroacetate

UN2948 3–Trifluoromethylaniline

UN2949 Sodium hydrosulfide, with not less than 25 percent water of crystallization

UN2950 Magnesium granules, coated particle size not less than 149 microns

UN2956 5–tert–Butyl–2,4,6–trinitro–m–xylene or Musk xylene

UN2965 Boron trifluoride dimethyl etherate

UN2966 Thiogylcol

UN2967 Sulfamic acid

UN2968 Maneb stabilized or Maneb preparations, stabilized against self–heating

UN2969 Castor beans or Castor meal or Castor pomace or Castor flake

UN2974 Radioactive material, special form, n.o.s.

UN2982 Radioactive material, n.o.s.

UN2983 Ethylene oxide and propylene oxide mixtures with not more than 30 percent ethylene oxide

UN2984 Hydrogen peroxide, aqueous solutions with not less than 8 percent but less than 20 percent hydrogen

peroxide (stabilized as necessary)

UN2985 Chlorosilanes, flammable, corrosive, n.o.s.

UN2986 Chlorosilanes, corrosive, flammable, n.o.s.

UN2987 Chlorosilanes, corrosive, n.o.s.

UN2988 Chlorosilanes, water–reactive, flammable, corrosive, n.o.s.

UN2989 Lead phosphite, dibasic

UN2990 Life–saving appliances, self–inflating

UN2991 Carbamate pesticide, liquid, toxic, flammable, flashpoint not less than 23° C

UN2992 Carbamate pesticides, liquid, toxic

UN2993 Arsenical pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN2994 Arsenical pesticides, liquid, toxic

UN2995 Organochlorine pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN2996 Organochlorine pesticide, liquid, toxic

UN2997 Triazine pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

Appendix B Hazardous, Restricted, and Perishable Mail

328 Publication 52

UN2998 Triazine pesticides, liquid, toxic

UN3002 Phenyl urea pesticides, liquid, toxic

UN3005 Thiocarbamate pesticides, liquid, flammable, toxic, flashpoint not less than 23° C

UN3006 Thiocarbamate pesticide, liquid, toxic

UN3009 Copper based pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3010 Copper based pesticides, liquid, toxic

UN3011 Mercury based pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3012 Mercury based pesticides, liquid, toxic

UN3013 Substituted nitrophenol pesticides, liquid, toxic flammable flashpoint not less than 23° C

UN3014 Substituted nitrophenol pesticides, liquid, toxic

UN3015 Bipyridilium pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3016 Bipyridilium pesticides, liquid, toxic

UN3017 Organophosphorus pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3018 Organophosphorus pesticides, liquid, toxic

UN3019 Organotin pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3020 Organotin pesticides, liquid, toxic

UN3021 Pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN3022 1,2–Butylene oxide, stabilized

UN3023 2–Methyl–2–heptanethiol

UN3024 Coumarin derivative pesticides, liquid, flammable, toxic, flashpoint less than 23° C

UN3025 Coumarin derivative pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

UN3026 Coumarin derivative pesticides, liquid, toxic

UN3027 Coumarin derivative pesticides, solid, toxic

UN3028 Batteries, dry, containing potassium hydroxide solid, electric, storage

UN3048 Aluminum phosphide pesticides

UN3049 Metal alkyl halides, water–reactive, n.o.s. or Metal aryl halides, water–reactive, n.o.s.

UN3050 Metal alkyl hydrides, water–reactive, n.o.s. or Metal aryl hydrides, water–reactive, n.o.s.

UN3053 Magnesium alkyls

UN3054 Cyclohexyl mercaptan

UN3055 2–(2–Aminoethoxy) ethanol

UN3056 n–Heptaldehyde

UN3057 Trifluoroacetyl chloride

UN3064 Nitroglycerin, solution in alcohol, with more than 1 percent but not more than 5 percent nitroglycerin

UN3065 Alcoholic beverages

UN3066 Paint or Paint related material

UN3070 Ethylene oxide and dichlorodifluoromethane mixture with not more than 12.5 percent ethylene oxide

UN3071 Mercaptans, liquid, toxic, flammable, n.o.s. or Mercaptan mixtures, liquid, toxic, flammable, n.o.s.,

flashpoint not less than 23° C

UN3072 Life–saving appliances, not self–inflating containing dangerous goods as equipment

UN3073 Vinylpyridines, stabilized

NA3077 Hazardous waste, solid, n.o.s. or Other regulated substances, solid, n.o.s.

UN3077 Environmentally hazardous substances, solid, n.o.s. (not including waste)

UN3078 Cerium, turnings or gritty powder

UN3079 Methacrylonitrile, inhibited

UN3080 Isocyanates, toxic, flammable, n.o.s. or Isocyanate solutions, toxic, flammable, n.o.s. flashpoint not

less than 23° C but not more than 6° C and boiling point less than 300° C

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 329

NA3082 Hazardous waste, liquid, n.o.s. or Other regulated substances, liquid, n.o.s.

UN3082 Environmentally hazardous substances, liquid, n.o.s. (not including waste)

UN3083 Perchloryl fluoride

UN3084 Corrosive solids, oxidizing, n.o.s.

UN3085 Oxidizing solid, corrosive, n.o.s.

UN3086 Toxic solids, oxidizing, n.o.s.

UN3087 Oxidizing solid, toxic, n.o.s.

UN3088 Self–heating solid, organic, n.o.s.

UN3089 Metal powders, flammable, n.o.s.

UN3090 Lithium metal batteries (including lithium alloy batteries)

UN3091 Lithium metal batteries (including lithium alloy batteries) contained in, or packed with, equipment

UN3091 Lithium batteries packed with equipment

UN3092 1–Methoxy–2–propanol

UN3093 Corrosive liquids, oxidizing, n.o.s.

UN3094 Corrosive liquids, water–reactive, n.o.s.

UN3095 Corrosive solids, self–heating, n.o.s.

UN3096 Corrosive solids, water–reactive, n.o.s.

UN3097 Flammable solid, oxidizing, n.o.s.

UN3098 Oxidizing liquid, corrosive, n.o.s.

UN3099 Oxidizing liquid, toxic, n.o.s.

UN3100 Oxidizing solid, self–heating, n.o.s.

UN3101 Organic peroxide type B, liquid

UN3102 Organic peroxide type B, solid

UN3103 Organic peroxide type C, liquid

UN3104 Organic peroxide type C, solid

UN3105 Organic peroxide type D, liquid

UN3106 Organic peroxide type D, solid

UN3107 Organic peroxide type E, liquid

UN3108 Organic peroxide type E, solid

UN3109 Organic peroxide type F, liquid

UN3110 Organic peroxide type F, solid

UN3111 Organic peroxide type B, liquid, temperature controlled

UN3112 Organic peroxide type B, solid, temperature controlled

UN3113 Organic peroxide type C, liquid, temperature controlled

UN3114 Organic peroxide type C, solid, temperature controlled

UN3115 Organic peroxide type D, liquid, temperature controlled

UN3116 Organic peroxide type D, solid, temperature controlled

UN3117 Organic peroxide type E, liquid, temperature controlled

UN3118 Organic peroxide type E, solid, temperature controlled

UN3119 Organic peroxide type F, liquid, temperature controlled

UN3120 Organic peroxide type F, solid, temperature controlled

UN3121 Oxidizing solid, water–reactive, n.o.s.

UN3122 Toxic liquids, oxidizing, n.o.s.

UN3123 Toxic liquids, water–reactive, n.o.s.

UN3124 Toxic solids, self–heating, n.o.s.

UN3125 Toxic solids, water–reactive, n.o.s.

Appendix B Hazardous, Restricted, and Perishable Mail

330 Publication 52

UN3126 Self–heating solid, corrosive, organic, n.o.s.

UN3127 Self–heating solid, oxidizing, n.o.s.

UN3128 Self–heating solid, toxic, organic, n.o.s.

UN3129 Water–reactive liquid, corrosive, n.o.s.

UN3130 Water–reactive liquid, toxic, n.o.s.

UN3131 Water–reactive solid, corrosive, n.o.s.

UN3132 Water–reactive solid, flammable, n.o.s.

UN3133 Water–reactive solid, oxidizing, n.o.s.

UN3134 Water–reactive solid, toxic, n.o.s.

UN3135 Water–reactive solid, self–heating, n.o.s.

UN3136 Trifluoromethane, refrigerated liquid

UN3137 Oxidizing solid, flammable, n.o.s.

UN3138 Ethylene, acetylene and propylene in mixture, refrigerated liquid with at least 71.5 percent ethylene

with not more than 22.5 percent acetylene and not more than 6 percent propylene

UN3139 Oxidizing liquid, n.o.s.

UN3140 Alkaloids, liquid, n.o.s., or Alkaloid salts, liquid, n.o.s.

UN3141 Antimony compounds, inorganic, liquid, n.o.s.

UN3142 Disinfectants, liquid, toxic, n.o.s.

UN3143 Dyes, solid, toxic, n.o.s. or Dye intermediates, solid, toxic, n.o.s.

UN3144 Nicotine compounds, liquid, n.o.s. or Nicotine preparations, liquid, n.o.s.

UN3145 Alkylphenols, liquid, n.o.s. (including C2–C12 homologues)

UN3146 Organotin compounds, solid, n.o.s.

UN3147 Dyes, solid, corrosive, n.o.s. or Dye intermediates, solid, corrosive, n.o.s.

UN3148 Water–reactive liquid, n.o.s.

UN3149 Hydrogen peroxide and peroxyacetic acid mixtures, stabilized with acids, water, and not more than 5

percent peroxyacetic acid

UN3150 Devices, small, hydrocarbon gas powered or Hydrocarbon gas refills for small devices with release

device

UN3151 Polyhalogenated biphenyls, liquid or Polyhalogenated terphenyls, liquid

UN3152 Polyhalogenated biphenyls, solid or Polyhalogenated terphenyls, solid

UN3153 Perfluoro(methyl vinyl ether)

UN3154 Perfluoro(ethyl vinyl ether)

UN3155 Pentachlorophenol

UN3156 Compressed gas, oxidizing, n.o.s.

UN3157 Liquified gas, oxidizing, n.o.s.

UN3158 Gas, refrigerated liquid, n.o.s. (cryogenic liquid)

UN3159 1,1,1,2–Tetrafluoroethane or Refrigerant gas R 134a

UN3160 Liquified gas, toxic, flammable, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3161 Liquified gas, flammable, n.o.s.

UN3162 Liquified gas, toxic, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3163 Liquified gas, n.o.s.

UN3164 Articles, pressurized pneumatic or Hydraulic containing non–flammable gas

UN3165 Aircraft hydraulic power unit fuel tank (containing a mixture of anhydrous hydrazine and monomethyl

hydrazine) (M86 fuel)

UN3166 Vehicle, flammable gas powered or Vehicle, fuel cell, flammable gas powered. Vehicle, flammable

liquid powered or Vehicle, fuel cell, flammable liquid powered

UN3167 Gas sample, non–pressurized, flammable, n.o.s., not refrigerated liquid

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 331

UN3168 Gas sample, non–pressurized, toxic, flammable, n.o.s., not refrigerated liquid

UN3169 Gas sample, non–pressurized, toxic, n.o.s., not refrigerated liquid

UN3170 Aluminum smelting by–products or Aluminum remelting by–products

UN3171 Battery–powered vehicle or Battery–powered equipment

UN3172 Toxins, extracted from living sources, liquid, n.o.s.

UN3174 Titanium disulphide

UN3175 Solids containing flammable liquid, n.o.s.

UN3176 Flammable solid, organic, molten, n.o.s.

NA3178 Smokeless powder for small arms (100 pounds or less)

UN3178 Flammable solid, inorganic, n.o.s.

UN3179 Flammable solid, toxic, inorganic, n.o.s.

UN3180 Flammable solid, corrosive, inorganic, n.o.s.

UN3181 Metal salts of organic compounds, flammable, n.o.s.

UN3182 Metal hydrides, flammable, n.o.s.

UN3183 Self–heating liquid, organic, n.o.s.

UN3184 Self–heating liquid, toxic, organic, n.o.s.

UN3185 Self–heating liquid, corrosive, organic, n.o.s.

UN3186 Self–heating liquid, inorganic, n.o.s.

UN3187 Self–heating liquid, toxic, inorganic, n.o.s.

UN3188 Self–heating liquid, corrosive, inorganic, n.o.s.

UN3189 Metal powder, self–heating, n.o.s.

UN3190 Self–heating solid, inorganic, n.o.s.

UN3191 Self–heating solid, toxic, inorganic, n.o.s.

UN3192 Self–heating solid, corrosive, inorganic, n.o.s.

UN3194 Pyrophoric liquid, inorganic, n.o.s.

UN3200 Pyrophoric solid, inorganic, n.o.s.

UN3203 Pyrophoric organometallic compound, water–reactive, n.o.s.

UN3205 Alkaline earth metal alcoholates, n.o.s.

UN3206 Alkali metal alcoholates, self–heating, corrosive, n.o.s.

UN3207 Organometallic compound or Compound solution or Compound dispersion, water–reactive,

flammable, n.o.s.

UN3208 Metallic substances, water–reactive, n.o.s.

UN3209 Metallic substance, water–reactive, self–heating, n.o.s.

UN3210 Chlorates, inorganic, aqueous solutions, n.o.s.

UN3211 Perchlorates, inorganic, aqueous solution, n.o.s.

UN3212 Hypochlorites, inorganic, n.o.s.

UN3213 Bromates, inorganic, aqueous solution, n.o.s.

UN3214 Permanganates, inorganic, aqueous solution, n.o.s.

UN3215 Persulfates, inorganic, n.o.s.

UN3216 Persulfates, inorganic, aqueous solution, n.o.s.

UN3218 Nitrates, inorganic, aqueous solution, n.o.s.

UN3219 Nitrites, inorganic, aqueous solution, n.o.s.

UN3220 Pentafluoroethane or Refrigerant gas R 125

UN3221 Self–reactive liquid type B

UN3222 Self–reactive solid type B

UN3223 Self–reactive liquid type C

Appendix B Hazardous, Restricted, and Perishable Mail

332 Publication 52

UN3224 Self–reactive solid type C

UN3225 Self–reactive liquid type D

UN3226 Self–reactive solid type D

UN3227 Self–reactive liquid type E

UN3228 Self–reactive solid type E

UN3229 Self–reactive liquid type F

UN3230 Self–reactive solid type F

UN3231 Self–reactive liquid type B, temperature controlled

UN3232 Self–reactive solid type B, temperature controlled

UN3233 Self–reactive liquid type C, temperature controlled

UN3234 Self–reactive solid type C, temperature controlled

UN3235 Self–reactive liquid type D, temperature controlled

UN3236 Self–reactive solid type D, temperature controlled

UN3237 Self–reactive liquid type E, temperature controlled

UN3238 Self–reactive solid type E, temperature controlled

UN3239 Self–reactive liquid type F, temperature controlled

UN3240 Self–reactive solid type F, temperature controlled

UN3241 2–Bromo–2–nitropropane–1,3–diol

UN3242 Azodicarbonamide

UN3243 Solids containing toxic liquid, n.o.s.

UN3244 Solids containing corrosive liquid, n.o.s.

UN3246 Methanesulfonyl chloride

UN3247 Sodium peroxoborate, anhydrous

UN3248 Medicine, liquid, flammable, toxic, n.o.s.

UN3249 Medicine, solid, toxic, n.o.s.

UN3250 Chloroacetic acid, molten

UN3251 Isosorbide–5–mononitrate

UN3252 Difluoromethane or Refrigerant gas R 32

UN3253 Disodium trioxosilicate

UN3254 Tributylphosphane

UN3255 tert–Butyl hypochlorite

UN3256 Elevated temperature liquid, flammable, n.o.s., with flashpoint above 37.8° C, at or above its

flashpoint

UN3257 Elevated temperature liquid, n.o.s., at or above 100° C and below its flashpoint (including molten

metals, molten salts, etc.)

UN3258 Elevated temperature solid, n.o.s., at or above 240° C, see 49 CFR 173.247(h)(4)

UN3259 Amines, solid, corrosive, n.o.s. or Polyamines, solid, corrosive, n.o.s.

UN3260 Corrosive solid, acidic, inorganic, n.o.s.

UN3261 Corrosive solid, acidic, organic, n.o.s.

UN3262 Corrosive solid, basic, inorganic, n.o.s.

UN3263 Corrosive solid, basic, organic, n.o.s.

UN3264 Corrosive liquid, acidic, inorganic, n.o.s.

UN3265 Corrosive liquid, acidic, organic, n.o.s.

UN3266 Corrosive liquid, basic, inorganic, n.o.s.

UN3267 Corrosive liquid, basic, organic, n.o.s.

UN3268 Air bag inflators, or Air bag modules, or Seatbelt pretensioners

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 333

UN3269 Polyester resin kit

UN3270 Nitrocellulose membrane filters

UN3271 Ethers, n.o.s.

UN3272 Esters, n.o.s.

UN3273 Nitriles, flammable, toxic, n.o.s.

UN3274 Alcoholates solution, n.o.s., in alcohol

UN3275 Nitriles, toxic, flammable, n.o.s.

UN3276 Nitriles, toxic, n.o.s.

UN3277 Chloroformates, toxic, corrosive, n.o.s.

UN3278 Organophosphorus compound, toxic n.o.s.

UN3279 Organophosphorus compound, toxic, flammable, n.o.s.

UN3280 Organoarsenic compound, n.o.s.

UN3281 Metal carbonyls, n.o.s.

UN3282 Organometallic compound, toxic n.o.s.

UN3283 Selenium compound, n.o.s.

UN3284 Tellurium compound, n.o.s.

UN3285 Vanadium compound, n.o.s.

UN3286 Flammable liquid, toxic, corrosive, n.o.s.

UN3287 Toxic liquid, inorganic, n.o.s.

UN3288 Toxic solid, inorganic, n.o.s.

UN3289 Toxic liquid, corrosive, inorganic, n.o.s.

UN3290 Toxic solid, corrosive, inorganic, n.o.s.

UN3291 Regulated medical waste (sharps) or Regulated medical waste (non–sharps)

UN3292 Batteries, containing sodium or Cells, containing sodium

UN3293 Hydrazine, aqueous solution with not more than 37 percent hydrazine, by mass

UN3294 Hydrogen, cyanide, solution in alcohol with not more than 45 percent hydrogen cyanide

UN3295 Hydrocarbons, liquid, n.o.s.

UN3296 Heptafluoropropane or Refrigerant gas R 227

UN3297 Ethylene oxide and chlorotetrafluoroethane mixture with not more than 8.8 percent ethylene oxide

UN3298 Ethylene oxide and pentafluoroethane mixture with not more than 7.9 percent ethylene oxide

UN3299 Ethylene oxide and tetrafluoroethane mixture with not more than 5.6 percent ethylene oxide

UN3300 Ethylene oxide and carbon dioxide mixtures with more than 87 percent ethylene oxide

UN3301 Corrosive liquids, self–heating, n.o.s.

UN3302 2–Dimethylaminoethyl acrylate

UN3303 Compressed gas, toxic, oxidizing, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3304 Compressed gas, toxic, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3305 Compressed gas, toxic, flammable, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3306 Compressed gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3307 Liquified gas, toxic, oxidizing, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3308 Liquified gas, toxic, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3309 Liquified gas, toxic, flammable, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3310 Liquified gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D

UN3311 Gas, refrigerated liquid, oxidizing, n.o.s. (cryogenic liquid)

UN3312 Gas, refrigerated liquid, flammable, n.o.s. (cryogenic liquid)

UN3313 Organic pigments, self–heating

UN3314 Plastic molding compound in dough, sheet, or extruded rope form evolving flammable vapor

Appendix B Hazardous, Restricted, and Perishable Mail

334 Publication 52

UN3316 First aid kits

UN3317 2–Amino–4,6–Dinitrophenol, wetted with not less than 20 percent water by mass

UN3318 Ammonia solution, relative density less than 0.880 at 15° C in water, with more than 50 percent

ammonia

UN3319 Nitroglycerin mixture, desensitized, solid, n.o.s. with more than 2 percent but not more than 10

percent nitroglycerin, by mass

UN3320 Sodium borohydride and sodium hydroxide solution, with not more than 12 percent sodium

borohydride and not more than 40 percent sodium hydroxide by mass

UN3423 Tetramethylammonium hydroxide, solid

NA3334 Self–defense spray, non–pressurized

UN3334 Aviation regulated liquid, n.o.s.

UN3335 Aviation regulated solid, n.o.s.

UN3336 Mercaptans, liquid, flammable, n.o.s. or Mercaptan mixture, liquid, flammable, n.o.s.

UN3337 Refrigerant gas R 404A

UN3338 Refrigerant gas R 407A

UN3339 Refrigerant gas R 407B

UN3340 Refrigerant gas R 407C

UN3341 Thiourea dioxide

UN3342 Xanthates

UN3343 Nitroglycerin mixture, desensitized, liquid, flammable, n.o.s. with not more than 30 percent

nitroglycerin, by mass

UN3344 Pentaerythrite tetranitrate mixture, desensitized, solid, n.o.s. with more than 10 percent but not more

than 20 percent PETN, by mass

UN3345 Phenoxyacetic acid derivative pesticide, solid, toxic

UN3346 Phenoxyacetic acid derivative pesticide, liquid, flammable, toxic flashpoint less than 23° C

UN3347 Phenoxyacetic acid derivative pesticide, liquid, toxic, flammable, flashpoint not less than 23° C

UN3348 Phenoxyacetic acid derivative pesticide, liquid, toxic

UN3349 Pyrethroid pesticide, solid, toxic

UN3350 Pyrethroid pesticide, liquid, flammable, toxic, flashpoint less than 23° C

UN3351 Pyrethroid pesticide, liquid, flammable, toxic, flashpoint less than 23° C

UN3352 Pyrethroid pesticide, liquid, toxic

UN3354 Insecticide gases, flammable, n.o.s

UN3355 Insecticide gases, toxic, flammable, n.o.s., Inhalation hazard A, B, C or D

UN3356 Oxygen generator, chemical

UN3360 Fiber, vegetable, dry

UN3361 Chlorosilanes, toxic, corrosive, n.o.s.

UN3362 Chlorosilanes, toxic, corrosive, flammable, n.o.s.

UN3363 Dangerous Goods in Machinery or Dangerous Goods in Apparatus

UN3364 Trinitrophenol (picric acid), wetted with not less than 10 percent water by mass

UN3365 Trinitrochlorobenzene (picryl chloride), wetted, with not less than 10 percent water by mass

UN3366 Trinitrotoluene (TNT) wetted, with not less than 10 percent water by mass

UN3367 Trinitrobenzene, wetted, with not less than 10 percent water, by mass

UN3368 Trinitrobenzoic acid, wetted with not less than 10 percent water, by mass

UN3370 Urea nitrate, wetted with not less than 10 percent water, by mass

UN3373 Biological substance, Category B

UN3379 Desensitized explosives, liquid, n.o.s.

UN3380 Desensitized explosives, solid, n.o.s.

Numerical Listing of Proper Shipping Names by Identification (ID) Number Appendix B

September 7, 2023 335

UN3381

Toxic by inhalation liquid, n.o.s. with an LC50 lower than or equal to 200 ml/m

and saturated vapor

concentration greater than or equal to 500 LC50

UN3382

Toxic by inhalation liquid, n.o.s. with an LC50 lower than or equal to 1000 ml/m

and saturated vapor

concentration greater than or equal to 10 LC50

UN3383

Toxic by inhalation liquid, flammable, n.o.s. with an LC50 lower than or equal to 200 ml/m

and

saturated vapor concentration greater than or equal to 500 LC50

UN3384

Toxic by inhalation liquid, flammable, n.o.s. with an LC50 lower than or equal to 1000 ml/m

and

saturated vapor concentration greater than or equal to 10 LC50

UN3385

Toxic by inhalation liquid, water-reactive, n.o.s. with an LC50 lower than or equal to 200 ml/m

and

saturated vapor concentration greater than or equal to 500 LC50

UN3386

Toxic by inhalation liquid, water-reactive, n.o.s. with an LC50 lower than or equal to 1000 ml/m

and

saturated vapor concentration greater than or equal to 10 LC50

UN3387

Toxic by inhalation liquid, oxidizing, n.o.s. with an LC50 lower than or equal to 200 ml/m

and

saturated vapor concentration greater than or equal to 500 LC50

UN3388

Toxic by inhalation liquid, oxidizing, n.o.s. with an LC50 lower than or equal to 1000 ml/m

and

saturated vapor concentration greater than or equal to 10 LC50

UN3389

Toxic by inhalation liquid, corrosive, n.o.s. with an LC50 lower than or equal to 200 ml/m

and

saturated vapor concentration greater than or equal to 500 LC50

UN3390

Toxic by inhalation liquid, corrosive, n.o.s. with an LC50 lower than or equal to 1000 ml/m

and

saturated vapor concentration greater than or equal to 10 LC50

UN3401 Alkali metal amalgam, solid

UN3402 Alkaline earth metal amalgams, solid

UN3405 Barium chlorate, solution

UN3406 Barium perchlorate, solution

UN3407 Chlorate and magnesium chloride mixture, solution

UN3409 Chloronitrobenzene, liquid

UN3410 4–Chloro–o–toluidine hydrochloride, solution

UN3416 Chloroacetophenone (CN), liquid

UN3417 Xylyl bromide, solid

UN3420 Boron trifluoride propionic acid complex, solid

UN3424 Ammonium dintro–o–cresolate, solution

UN3425 Bromoacetic acid, solid

UN3426 Acrylamide, solution

UN3427 Chlorobenzyl chlorides, solid

UN3428 3–Chloro–4–methylphenyl isocyanate, solid

UN3429 Chlorotoluidines, liquid

UN3430 Xylenols, liquid

UN3437 Chlorocresols, solid

UN3441 Chlorodinitrobenzenes, solid

UN3442 Dichloroanilines, solid

UN3443 Dinitrobenzenes, solid

UN3448 Tear gas substances, solid, n.o.s

UN3449 Bromobenzyl cyanides, solid

UN3451 Toluidines solid

UN3452 Xylidines, solid

UN3454 Dinitrotoluenes, solid

Appendix B Hazardous, Restricted, and Perishable Mail

336 Publication 52

UN3455 Cresols, solid

UN3457 Chloronitrotoluenes, solid

UN3460 N-Ethylbenzyltoluidines, solid

UN3462 Toxins, extracted from living sources, solid, n.o.s.

UN3472 Crotonic acid, liquid

UN3475 Ethanol and gasoline mixture or Ethanol and motor spirit mixture or Ethanol and petrol mixture, with

more than 10 percent ethanol

UN3480 Lithium-ion batteries (including lithium polymer batteries)

UN3481 Lithium-ion batteries (including lithium polymer batteries) contained in, or packed with, equipment

UN3485 Calcium hypochlorite, dry, corrosive or Calcium hypochlorite mixtures, dry, corrosive with more than

39 percent available chlorine (8.8 percent available oxygen)

UN3486 Calcium hypochlorite mixture, dry, corrosive with more than 10 percent but not more than 39 percent

available chlorine

UN3487 Calcium hypochlorite, hydrated, corrosive or Calcium hypochlorite, hydrated mixture, corrosive with

not less than 5.5 percent but not more than 16 percent water

UN3488

Toxic by inhalation liquid, flammable, corrosive, n.o.s. with an LC50 lower than or equal to 200 ml/m

and saturated vapor concentration greater than or equal to 500 LC50

UN3489 Toxic by inhalation liquid, flammable, corrosive, n.o.s. with an LC50 lower than or equal to 1000 ml/

and saturated vapor concentration greater than or equal to 10 LC50

UN3490 Toxic by inhalation liquid, water-reactive, flammable, n.o.s. with an LC50 lower than or equal to 200

ml/m

and saturated vapor concentration greater than or equal to 500 LC50-

UN3491 Toxic by inhalation liquid, water-reactive, flammable, n.o.s. with an LC50 lower than or equal to 1000

ml/m

and saturated vapor concentration greater than or equal to 10 LC50-

UN3496 Batteries, nickel-metal hydride see Batteries, dry. Sealed, n.o.s. for nickel metal hydride batteris

transported by modes other than vessel

UN3500 Chemical under pressure, n.o.s.

UN3501 Chemical under pressure, flammable, n.o.s.

UN3502 Chemical under pressure, toxic, n.o.s.

UN3503 Chemical under pressure, corrosive, n.o.s.

UN3504 Chemical under pressure, flammable, toxic, n.o.s.

UN3505 Chemical under pressure, flammable, corrosive, n.o.s.

UN3506 Mercury contained in manufactured articles

ID8000 Consumer Commodity

NA9035 Gas identification set

NA9191 Chlorine dioxide, hydrate, frozen

NA9202 Carbon monoxide, refrigerated liquid (cryogenic liquid)

NA9206 Methyl phosphonic dichloride

NA9260 Aluminum, molten

NA9263 Chloropivaloyl chloride

NA9264 3,5–Dichloro–2,4,6–trifluoropyridine

NA9269 Trimethoxysilane

September 7, 2023 337

Appendix C

USPS Packaging Instructions for Mailable

Hazardous Materials

These Postal Service packaging instructions are for mailable types of

hazardous materials. The numeric digits 1 through 9 correspond to the

appropriate hazard class. The alpha characters differentiate the separate

groups of materials within a hazard class. Packaging instructions 10A

through 10C provide packaging information relating to special provisions not

associated with a specific hazard class. Postal Service packaging

instructions are provided as follows:

Hazard Class 1: Explosives

 1A Toy Propellant Devices

 1B Safety Fuse

Hazard Class 2: Gases

 2A Flammable Gases

 2B Nonflammable Gases

 2C Fire Extinguishers

 2D Foodstuffs and Soap Products

 2E Audible Fire Alarm Systems

 2F Biological Products or Medical Preparations

Hazard Class 3: Flammable and Combustible Liquids

 3A Flammable Liquids

 3B Combustible Liquids

 3C Flammable Liquid or Gas Lighters

 3D Ethanol-based Flammable Liquids and Solids

Hazard Class 4: Flammable Solids

 4A Flammable Solids

 4B Safety Matches

Hazard Class 5: Oxidizing Substances, Organic Peroxides

 5A Oxidizing Substances, Organic Peroxides

Hazard Class 6: Toxic Substances and Infectious Substances

 6A Toxic Substances

 6B Toxic Substances with LD

50 Oral Toxicity of 50 mg/kg or Less

 6C Category B Infectious Substances

 6D Sharps Waste and Other Regulated Medical Waste

Appendix C Hazardous, Restricted, and Perishable Mail

338 Publication 52

 6E Used Health Care Products

 6F Forensic Material

 6G Nonregulated Infectious Materials

 6H Exempt Human or Animal Specimens

Hazard Class 7: Radioactive Materials

 7A Radioactive Materials

Hazard Class 8: Corrosives

 8A Corrosives

 8B Nonspillable Wet Battery

 8C Manufactured Devices that Contain Small Amounts of Mercury

Hazard Class 9: Miscellaneous Hazardous Materials

 9A Dry Ice (Carbon Dioxide Solid)

 9B Magnetized Materials

 9C Miscellaneous Hazardous Materials

 9D Lithium Metal and Lithium-ion Cells and Batteries — Domestic

 9E Lithium Metal and Lithium-ion Cells and Batteries — International

and APO/FPO/DPO

Category 10: Other Packaging Instructions

 10A Small-Quantity Provision

 10B Excepted Quantity Provision

 10C Cremated Remains

 10D Adult Bird Boxes

USPS Packaging Instruction 1A

Toy Propellant Devices

The proper shipping name for a mailable toy propellant device is “model

rocket motor” or “igniter.” A device that is assigned identification number

NA0323 or UN0454 and classed as a Division 1.4S explosive is eligible for

mailing in domestic mail via surface transportation only, provided that all

requirements are met and the device is properly packaged as follows.

Proper Shipping Name and ID Number

 Model Rocket Motors, NA0323.

 Igniters, UN0454.

Required Authorization

Prior written permission must be obtained from:

DIRECTOR, PRODUCT CLASSIFICATION

USPS HEADQUARTERS

475 L’ENFANT PLAZA SW, ROOM 4446

WASHINGTON, DC 20260

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 339

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation with prior

approval. Each device must meet the specifications in

341.22a.

Design Specifications

Mailable devices must meet each of the following conditions:

 Each device must be ignitable by electrical means only.

 Each device must contain no more than 30g (1.07 ounces) of propellant.

 Each device must produce less than 80 newton seconds of total

impulse with thrust duration not less than 0.050 second.

 Each device must be constructed so that all chemical ingredients are

preloaded into a cylindrical paper or similarly constructed nonmetallic

tube that does not fragment into sharp, hard pieces.

 Each device must be designed so that it will not burst under normal

conditions.

 Each device must be incapable of spontaneous ignition under 500° F.

 Each device must not contain any type of explosive or pyrotechnic

warhead other than a small, activation-charge, parachute-recovery

system.

Required Packaging

Primary Receptacle

 Each device must be packed in a securely sealed primary receptacle.

 Multiple primary receptacles are permitted within a single mailpiece.

 Each primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent breakage.

Outer Shipping Container

 A strong outer packaging that is capable of firmly and securely holding

the primary receptacle(s) and cushioning material is required.

 Each mailpiece must not exceed a total weight of 25 pounds.

Marking

 Each outer packaging must be clearly marked on the address side with

“Toy Propellant Devices,” followed by the applicable proper shipping

name and UN or NA number. The markings “Surface Only” or “Surface

Mail Only” and “Handle With Care” must also appear on the address

side of the mailpiece. A DOT hazardous materials warning label must

not be affixed.

 A complete mailing address and return address must be used.

Documentation

 A properly completed shipper's declaration for dangerous goods must

be prepared in triplicate and affixed to the outside of the mailpiece.

Note: Full responsibility rests with the mailer to comply with Bureau of

Alcohol, Tobacco, Firearms, and Explosives (BATFE) regulations before

Appendix C Hazardous, Restricted, and Perishable Mail

340 Publication 52

mailing. At the time of mailing, the mailer must present to the Postal

Service acceptance clerk a legible photocopy of the Product

Classification director’s approval letter.

USPS Packaging Instruction 1B

Safety Fuse

Safety fuses consist of a core of black powder overspun with yarns,

waterproofing compounds, and/or tapes. A safety fuse assigned

identification number UN0105 and classed as a Division 1.4S explosive may

be mailed only as permitted in

341.22b and when properly packaged as

follows.

Proper Shipping Name

 Safety Fuse.

ID Number

 UN0105.

Required Authorization

Prior written permission must be obtained from:

DIRECTOR, PRODUCT CLASSIFICATION

USPS HEADQUARTERS

475 L’ENFANT PLAZA SW, ROOM 4446

WASHINGTON, DC 20260

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation with prior

approval.

Required Packaging

Primary Receptacle

 Each device must be packed in a securely sealed primary receptacle.

 Multiple primary receptacles are permitted within a single mailpiece.

Cushioning Material

 Each primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent breakage.

Outer Packaging

 A strong outer packaging that is capable of firmly and securely holding

the primary receptacle(s) and cushioning material is required.

 The outer packaging must be made of fiberboard, wood, or metal.

Friction closures or paperboard containers are not acceptable.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 341

Marking

 The outside of the mailpiece must be clearly marked on the address

side with “Safety Fuse, UN0105” and “Surface Only” or “Surface Mail

Only.”

 A complete mailing address and return address must be used.

Documentation

 A properly completed shipper's declaration for dangerous goods must

be prepared in triplicate, and affixed to the outside of the mailpiece.

Note: Full responsibility rests with the mailer to comply with Bureau of

Alcohol, Tobacco, Firearms, and Explosives (BATFE) regulations before

mailing. At the time of mailing, the mailer must present to the Postal

Service acceptance clerk a legible photocopy of the Product

Classification director’s approval letter.

USPS Packaging Instruction 2A

Flammable Gases

A Class 2, Division 2.1 flammable gas that qualifies as a Limited Quantity

surface material is mailable provided that all applicable requirements in

342

are met and it is properly packaged as follows.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 The capacity of an other-than-metal (nonmetal) primary receptacle

must be 4 fluid ounces (7.22 cubic inches) or less per mailpiece.

 The capacity of a metal primary receptacle must be 33.8 fluid ounces

(1-liter or 61.0 cubic inches) or less per mailpiece.

 The liquid content of the material and the gas must not completely fill

the primary receptacle at 130° F.

 A DOT 2P container must be used if the internal pressure is from

140

psig to 160 psig at 130° F (55° C). A DOT 2Q container must be

used if the pressure is from 161 psig to 180 psig at 130° F (55° C).

 A container with an internal pressure more than 180 psig at 130° F

(55°

C) is prohibited from mailing.

Appendix C Hazardous, Restricted, and Perishable Mail

342 Publication 52

 Primary receptacles must have recessed valves, screw-thread caps,

tap closures, or other means to prevent accidental discharge. Valves

and fittings must be protected to ensure the integrity of the receptacle

during transport.

Cushioning Material

 Sufficient cushioning material must surround the primary receptacle to

absorb shock and prevent damage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

 Multiple primary receptacles may be securely packed within a single

strong outer packaging, provided the total volume of flammable gas

does not exceed 33.8 fluid ounces (1 liter) per mailpiece.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

342.4b.

 A complete return and delivery address must be used.

USPS Packaging Instruction 2B

Nonflammable Gases

A Class 2, Division 2.2 nonflammable gas that qualifies as a Limited Quantity

air or Limited Quantity surface material is mailable provided that all

applicable requirements in

342 are met and it is properly packaged as

follows.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted with restrictions via air transportation and

permitted via surface transportation.

Required Packaging

Primary Receptacle(s)

 The capacity of an other-than-metal (nonmetal) primary receptacle

must be 4 fluid ounces (7.22 cubic inches) or less per mailpiece.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 343

 The capacity of a metal primary receptacle must be 33.8 fluid ounces

(1-liter or 61.0 cubic inches) or less.

 The liquid content of the material and the gas must not completely fill

the primary receptacle at 130° F.

 A DOT 2P container must be used if the internal pressure is from

140

psig to 160 psig at 130° F (55° C). A DOT 2Q container must be

used if the pressure is from 161 psig to 180 psig at 130° F (55° C).

 A container with an internal pressure more than 180 psig at 130° F

(55°

C) is prohibited from mailing.

 The primary receptacle(s) must be packaged to protect valves and

fittings and to ensure integrity during transport.

 The primary receptacle(s) must have a recessed valve, screw-thread

cap, tap closure, or other means to prevent accidental discharge.

Cushioning Material

 Sufficient cushioning material must surround the primary receptacle to

absorb shock and prevent damage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle(s) and cushioning material is required.

 Multiple primary receptacles may be securely packed within a single

strong outer packaging.

 Each mailpiece must not exceed a total weight of 25 pounds.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 9

hazardous material warning label, Identification Number “ID8000,” and

the proper shipping name “Consumer Commodity.”

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity ground mark designating surface transportation,

prepared under

342.4c.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a mailable, nonflammable gas must have a

properly completed shipper's declaration for dangerous goods

prepared in triplicate and affixed to the outside of the mailpiece.

Appendix C Hazardous, Restricted, and Perishable Mail

344 Publication 52

USPS Packaging Instruction 2C

Fire Extinguishers

A fire extinguisher containing a Division 2.2 compressed, nonflammable gas

assigned UN1044 that can qualify as a Limited Quantity surface material is

mailable if it does not contain a methyl bromide gas mixture or sulfuric acid,

and, if the gas is nonflammable, nonpoisonous, or noncorrosive, as specified

in 49 CFR § 173.309(a). All applicable requirements in

342 must be met, and

it must be properly packaged as follows.

Proper Shipping Name

 Consumer Commodity.

ID Number

 UN1044 (see “Note” under Documentation below).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted with restrictions via air transportation and

permitted via surface transportation.

Required Packaging

Primary Receptacle

 The primary receptacle must be a DOT specification 2P or 2Q

container that meets the requirements in 49 CFR 173.309(a)(4).

 Only one primary receptacle not exceeding 1 liter (33.8 ounces) is

permitted per mailpiece.

Cushioning Material

 Sufficient cushioning material must surround the primary receptacle to

absorb shock and prevent damage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 9

hazardous material warning label (if applicable), Identification Number

“ID8000,” and the proper shipping name “Consumer Commodity.”

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

342.4c.

 A complete return and delivery address must be used.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 345

Documentation

 For air transportation, a properly completed shipper's declaration for

dangerous goods must be prepared in triplicate and affixed to the

outside of the mailpiece.

Note: Fire extinguishers assigned UN0275, UN0276, UN0323, and

UN0381 are prohibited from mailing. However, fire extinguishers

assigned UN1774 are mailable as Class 8 corrosives subject to the

limitations for corrosives in

348.

USPS Packaging Instruction 2D

Foodstuffs and Soap Products

Foodstuffs and soap products that are held in containers under pressure are

mailable in the domestic mail via surface transportation if they qualify as a

Limited Quantity surface material and all applicable requirements in

342 are

met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 Acceptable only in a nonrefillable metal primary receptacle not

exceeding 61.0 cubic inches (1 liter) with soluble or emulsified

compressed gas.

 Liquid content of the material and the gas must not completely fill the

primary receptacle at 130° F, the pressure in the primary receptacle

must be 140 psig or less at 130° F, and the metal primary receptacle

must be able to withstand one-and-one-half times the equilibrium

pressure of the content at 130° F.

Cushioning Material

 The primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent damage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

Appendix C Hazardous, Restricted, and Perishable Mail

346 Publication 52

 Multiple primary receptacles may be securely packed within a single

outer packaging up to a weight limit of 25 pounds (11.325 kg) per

mailpiece.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 The address side of each outer packaging must be clearly marked with

“Inside Containers Comply With Prescribed Regulations” per 49 CFR

§173.306(b)(1).

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

342.4c.

 A complete return and delivery address must be used.

USPS Packaging Instruction 2E

Audible Fire Alarm Systems

An audible fire alarm system powered by a compressed gas is mailable only

in domestic mail via surface transportation provided that the system qualifies

as a Limited Quantity surface material and all applicable requirements in

342

are met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 The content of the primary receptacle is a nonflammable,

nonpoisonous, or noncorrosive gas.

 The gas is contained within a metal primary receptacle that has a

capacity of 19.3 fluid ounces (35 cubic inches) or less, does not exceed

a pressure of 70 psig at 70° F, and is not completely filled at 130° F.

 Each nonrefillable primary receptacle must be designed to withstand a

burst pressure of not less than 4 times its charged pressure at 130° F.

 Each refillable primary receptacle must be designed to withstand a

burst pressure of not less than 5 times its charged pressure at 130° F.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 347

Cushioning Material

 The primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent breakage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning is required.

 Multiple primary receptacles may be securely packed within a single

outer packaging up to a weight limit of 25 pounds (11.325 kg) per

mailpiece.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

342.4c.

 A complete return and delivery address must be used.

USPS Packaging Instruction 2F

Biological Products or Medical Preparations

A product or preparation in a nonrefillable metal primary receptacle charged

with a nonflammable solution containing biological products or a medical

preparation that could deteriorate by heat may be accepted in the domestic

mail via surface transportation only provided that the item qualifies as a

Limited Quantity surface material, and all applicable requirements in

342 are

met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Packaging Requirements

Primary Receptacle

 Capacity of the primary receptacle must be 19.3 fluid ounces (35 cubic

inches) or less, pressure in the primary receptacle must be 140 psig or

less at 130° F, and the liquid content of product and gas must not

completely fill the container at 130° F.

Appendix C Hazardous, Restricted, and Perishable Mail

348 Publication 52

 If heated until the pressure in the primary receptacle is equivalent to

equilibrium pressure of content at 130° F, the primary receptacle must

be able to withstand leakage, distortion, or other damage or defects.

 Only one primary receptacle is permitted per mailpiece.

Cushioning Material

 The primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent breakage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning is required.

 Multiple primary receptacles are not permitted.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

342.4c.

 A complete return and delivery address must be used.

USPS Packaging Instruction 3A

Flammable Liquids

A flammable liquid having a flashpoint greater than 20° F (–7° C) but less than

100° F (38° C) is mailable in domestic mail via surface transportation, if the

liquid qualifies as a Limited Quantity surface material, and all applicable

requirements in

343 are met. Flammable liquids having a flashpoint of 20° or

less are not mailable.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail and APO/FPO/DPO: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 349

Required Packaging

Separate packaging requirements apply depending on the flashpoint of the

flammable liquid.

For flashpoint greater than 20º F (-7º C) but not more than 73º F

(23º C):

Primary Receptacle

 A metal primary receptacle must not exceed 1 quart.

 A nonmetal primary receptacle must not exceed 1 pint.

 The primary receptacle must have a screw cap (with minimum of

one-and-one-half turns), soldering clips, or other means of secure

closure (friction tops are not acceptable).

 Multiple primary receptacles are permitted, provided the aggregate

quantity of flammable material per mailpiece does not exceed 1 quart

for metal primary containers or 1 pint for nonmetal primary containers.

Cushioning Material and Secondary Packaging

 Enough cushioning material must surround the primary receptacles to

prevent breakage and absorb any potential leakage.

 The cushioning and primary receptacles must be packed in securely

sealed secondary packaging.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles, cushioning material, and secondary

packaging is required.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

343.3b.

 A complete return and delivery address must be used.

For flashpoint greater than 73º F (23º C) but less than 100º F

(38º

C):

Primary Receptacle

 A metal primary receptacle must not exceed 1 gallon.

 A nonmetal primary receptacle must not exceed 1 quart.

 The primary receptacle must have a screw cap (with minimum of

one-and-one-half turns), soldering clips, or other means of secure

closure (friction tops are not acceptable).

 Multiple primary receptacles are permitted, provided the aggregate

quantity of flammable material per mailpiece does not exceed 1 gallon

for metal primary containers or 1 quart for nonmetal primary

containers.

Appendix C Hazardous, Restricted, and Perishable Mail

350 Publication 52

Cushioning Material and Secondary Packaging

 Enough cushioning material must surround the primary receptacles to

prevent breakage and absorb any potential leakage.

 The cushioning and primary receptacles must be packed in securely

sealed secondary packaging.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles, cushioning material, and secondary

packaging is required.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

343.3b.

 A complete return and delivery address must be used.

For flashpoint of at least 100º F (38º C) but not more than 140º F

(60º C):

 Use Packaging Instruction 3B.

USPS Packaging Instruction 3B

Combustible Liquids

A combustible liquid having a flashpoint of 140° F (60° C) but no more than

200° F (93° C) is mailable if it qualifies as a Limited Quantity material in the

Postal Service for air or surface transportation and meets all applicable

requirements in

343. A flammable liquid having a flashpoint of at least 100° F

(38° C) but not more than 140° F (60° C) may be reclassed as a combustible

liquid within the limits of 49 CFR 173.120(b).

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: For flashpoints of at least 100º F (38º C), but not more

than 140º F (60º C), permitted only via surface transportation. For

flashpoints above 140° (60° C), permitted with restrictions via air

transportation and surface transportation.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 351

Required Packaging

Separate packaging requirements apply, depending on the flashpoint of the

combustible liquid.

For flashpoint of at least 100º F (38º C) but not more than 140º F

(60º C):

General

 Permitted only in domestic mail via surface transportation.

Primary Receptacle

 The capacity of a metal primary receptacle must not exceed 1 gallon.

 A nonmetal primary receptacle must not exceed 1 quart.

 Multiple primary receptacles are permitted, provided the aggregate

quantity of flammable material per mailpiece does not exceed 1 gallon

for metal primary containers or 1 quart for nonmetal primary

containers.

Absorbent and Cushioning Material

 Enough absorbent and cushioning material must surround the primary

receptacles to prevent breakage and absorb any potential leakage.

Secondary Packaging

 The cushioning and primary receptacles must be packed in a securely

sealed secondary packaging.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles, cushioning material, and secondary

packaging is required.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

343.3b.

 A complete return and delivery address must be used.

For flashpoint above 140º F (60º C) but not more than 200º F

(93º

C):

General

 Permitted in domestic mail via air or surface transportation.

Primary Receptacle

 The capacity of the primary receptacle must not exceed 1 gallon.

 Multiple primary receptacles are permitted, provided the aggregate

quantity of flammable material per mailpiece does not exceed 1 gallon.

Absorbent and Cushioning Material

 Enough absorbent and cushioning material must surround the primary

receptacles to prevent breakage and absorb any potential leakage.

Secondary Packaging

 The cushioning and primary receptacles must be packed in a securely

sealed secondary packaging.

Appendix C Hazardous, Restricted, and Perishable Mail

352 Publication 52

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles, cushioning material, and secondary

packaging is required.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 9

hazardous material warning label, Identification Number “ID8000,” and

the proper shipping name “Consumer Commodity.”

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

343.3b.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a properly completed shipper's declaration for

dangerous goods must be prepared in triplicate and affixed to the

outside of the mailpiece.

For flashpoint above 200º F (93º C):

General

 The material is not regulated as a hazardous material. Therefore, it is

permitted in domestic mail via air or surface transportation without

restriction when properly packaged to prevent leakage during

transport.

Primary Receptacle

 Each primary receptacle must be sturdy and have a secure method of

closure.

 Multiple primary receptacles may be enclosed within a single

mailpiece.

Absorbent and Cushioning Material

 Enough absorbent and cushioning material must surround the primary

receptacle to prevent breakage and absorb all potential leakage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

Marking

 A complete return address and delivery address must be used.

USPS Packaging Instruction 3C

Flammable Liquid or Gas Lighters

A lighter equipped with an ignition element and containing fuel is classified

as a Class 3 flammable liquid. A lighter containing a flammable gas is classed

as a Division 2.1 flammable gas. A lighter that contains either flammable

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 353

liquid or flammable gas is permitted in domestic mail via surface

transportation only with prior written approval, provided all the applicable

requirements of

343.25 are met.

Proper Shipping Name and ID Number

 Lighters or Lighter Refills, UN1057.

Required Authorization

 The design of the lighter must be certified by the lighter testing agency

authorized by the DOT Associate Administrator for Hazardous Material

Safety, per 49 CFR 173.21(i) and 173.308, and an Approval Number

(LAA****) must have been issued. The vendor in whose name the

authorization is being sought must submit a written request to the

director of Pricing and Classification Service Center (see

213 for

address).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 The design of the lighter must be approved by DOT (see “Required

Authorization” above).

Cushioning Material

 Sufficient cushioning material must be used to absorb shock and

protect the lighter from breakage.

Outer Packaging

 The packaging must be designed to protect the lighter's sparking

mechanism from accidental ignition caused by friction or external

pressure during transport.

 The outer packaging must be of sufficient strength to prevent the inner

contents from breaking or bursting through.

Marking

 The address side of each mailpiece must be clearly marked with

“Surface Only” or “Surface Mail Only” and “Lighters” or “Lighter Refills”

followed by the LAA**** Number.

 A complete return address and delivery address must be used.

Note: At the time of the mailer’s first mailing at each Postal Service

facility, the mailer must present to that facility a legible photocopy of the

PCSC director’s approval letter.

Appendix C Hazardous, Restricted, and Perishable Mail

354 Publication 52

USPS Packaging Instruction 3D

Ethanol-based Flammable Liquids and Solids

Certain limited quantities of flammable liquids and solids containing ethyl

alcohol are permitted in the domestic mail via air transportation, with special

authorization from the director, Product Classification, when all applicable

requirements in

343.27 are met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail and APO/FPO/DPO: Prohibited.

 Domestic Mail: Permitted via air transportation with special

authorization; or via surface transportation by following Packaging

Instruction 3A.

Required Packaging

Separate packaging requirements apply, dependent on the percentage of

ethyl alcohol and primary container used.

For content not more than 70% ethyl alcohol:

Primary Receptacle

 A nonglass primary receptacle must not exceed 16 ounces for liquids

or 1 pound for solids.

 A glass primary receptacle must not exceed 8 ounces for liquids or 1/2

pound for solids.

 The primary receptacle must have a screw cap (with minimum of one

and one-half turns), soldering clips, or other means of secure closure

(friction tops are not acceptable).

 Multiple primary receptacles are permitted when the total aggregate

mailpiece weight does not exceed 25

pounds.

 The total volume of flammable liquid in the mailpiece must not exceed

96 ounces.

 The total volume of flammable solids in the mailpiece must not exceed

16 pounds.

Cushioning Material

 Enough cushioning material must surround the primary receptacles to

prevent breakage and absorb any potential leakage.

 The cushioning and primary receptacles must be packed in securely

sealed outer packaging.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 355

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles and cushioning material is required.

Marking

 Each package must bear the text “Contains Air-Eligible Ethyl Alcohol

— Authorization No. #” on the outer packaging in at least 14-point

type.

 A complete company name, return address, and delivery address must

be applied to each outer package.

For content more than 70% ethyl alcohol:

Primary Receptacle

 The primary receptacle must not exceed 8 ounces for liquids or 1/2

pound for solids.

 The primary receptacle must have a screw cap (with minimum of one

and one-half turns), soldering clips, or other means of secure closure

(friction tops are not acceptable).

 Multiple primary receptacles are permitted when the total aggregate

mailpiece weight does not exceed 16

pounds.

 The total volume of flammable liquid in the mailpiece must not exceed

48 ounces.

 The total volume of flammable solids in the mailpiece must not exceed

8 pounds.

Cushioning Material

 Enough cushioning material must surround the primary receptacles to

prevent breakage and absorb any potential leakage.

 The cushioning and primary receptacles must be packed in securely

sealed outer packaging.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacles and cushioning material is required.

Marking

 Each package must bear the text “Contains Air-Eligible Ethyl

Alcohol

— Authorization No. #” on the outer packaging in at least

14-point type.

 A complete company name, return address, and delivery address must

be applied to each outer package.

Appendix C Hazardous, Restricted, and Perishable Mail

356 Publication 52

USPS Packaging Instruction 4A

Flammable Solids

A flammable solid that qualifies as a Limited Quantity surface material is

permitted in the domestic mail via surface transportation only, provided all

applicable requirements in

344 are met.

Proper Shipping Name

 Various (see Appendix A).

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 The primary receptacle must have a secure seal and together with its

contents must not exceed a weight of 1

pound.

 Multiple primary receptacles are permitted.

Cushioning Material

 Sufficient cushioning material must be used to absorb shock and the

primary receptacle from breakage.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

 Each mailpiece must not exceed a total weight of 25 pounds.

Marking

Labels and markings must be placed on the address side of the mailpiece

unless specified differently in

221.1 and 325.1.

 The outer packaging must bear an approved DOT Limited Quantity

surface mark designating surface transportation, prepared under

344.3a.

 A complete return and delivery address must be used.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 357

USPS Packaging Instruction 4B

Safety Matches

Safety matches (book, card, or strike-on-box) may be mailed only in

domestic mail via surface transportation, provided all applicable

requirements in

344 are met, including:

 They do not ignite spontaneously under conditions normally incident to

transportation or when subjected for eight consecutive hours to a

temperature of 200º F (93º C).

 They cannot be readily ignited by friction unless struck on their own or

on a similar box, card, or book.

Note: Strike-anywhere matches assigned UN1331 and other types of

matches assigned UN2254 or UN1945 are nonmailable.

Proper Shipping Name

 Matches, Safety.

ID Number

 UN1944.

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only via surface transportation.

Required Packaging

Primary Receptacle

 Mailable types of safety matches must be tightly packed in a securely

sealed primary receptacle to prevent any shifting or movement that

could cause accidental ignition by rubbing against adjoining items.

 Multiple primary receptacles are permitted per mailpiece.

Outer Packaging

 The outer packaging material must be made of fiberboard, wood, or

other equivalent and be strong enough to prevent the inner contents

from bursting through.

 The primary container(s) must be snugly packed within the outer

packaging.

 Each mailpiece must not exceed a total weight of 25 pounds.

Marking

 The address side of each mailpiece must be clearly marked “Surface

Only” or “Surface Mail Only” and either “Book Matches”, “Card

matches,” or “Strike-on-Box Matches,” as applicable.

 A complete return address and delivery address must be used.

Documentation

 A shipping paper is not required.

Appendix C Hazardous, Restricted, and Perishable Mail

358 Publication 52

USPS Packaging Instruction 5A

Oxidizing Substances, Organic Peroxides

An oxidizing substance or an organic peroxide that qualifies as a Limited

Quantity material within the Postal Service is permitted in the domestic mail

for air and surface transportation provided that all applicable requirements in

345 are met.

Proper Shipping Name

 Various (see Appendix A).

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted with restrictions via air transportation, or

surface transportation.

Required Packaging

Primary Receptacle

 For liquids, the capacity of the primary receptacle must not exceed

pint (.0473 liters).

 For solids, the weight of the contents of the primary receptacle must

not exceed 1 pound (.0453 kg).

 Multiple primary receptacles are permitted up to a total weight of

pounds per mailpiece.

Absorbent and Cushioning Material

 Enough absorbent and cushioning material must surround the primary

receptacle to prevent breakage and absorb all potential leakage.

Secondary Packaging

 For liquids only, the cushioning and primary receptacle must be

packed in a secondary leak-resistant packaging or material that is

securely sealed.

Outer Packaging

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

 Each mailpiece must not exceed a total weight of 25 pounds.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 359

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class

5.1 or 5.2 hazardous material warning label, Identification Number and

the proper shipping name.

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

343.3c.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a mailable material must have a properly

completed shipper’s declaration for dangerous goods that is prepared

in triplicate affixed to the outside of the mailpiece.

 The shipper’s declaration must be properly completed and signed by

the mailer.

USPS Packaging Instruction 6A

Toxic Substances

A Division 6.1 toxic substance that qualifies as a Limited Quantity material

within the Postal Service is permitted in the domestic mail via air or surface

transportation when all applicable requirements in

346 are met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via air transportation or surface

transportation.

Required Packaging

Primary Receptacle

 The primary container must be of sufficient strength and have a secure

method of closure.

 The capacity of the primary receptacle(s) per mailpiece must not

exceed 8

ounces.

Appendix C Hazardous, Restricted, and Perishable Mail

360 Publication 52

Absorbent and Cushioning Material

 Enough absorbent and cushioning material must surround the primary

receptacle to prevent breakage and absorb all potential leakage.

Outer Shipping Container

 Strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

 The inner receptacle and cushioning material must fit snugly within the

outer packaging.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 9

hazardous material warning label, Identification Number “ID8000,” and

the proper shipping name “Consumer Commodity.”

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

342.4c.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a mailable material must have a properly

completed shipper's declaration for dangerous goods that is prepared

in triplicate and affixed to the outside of the mailpiece.

USPS Packaging Instruction 6B

Toxic Substances with LD

Oral Toxicity of

50 mg/kg or Less

A Division 6.1 toxic substance having an LD

for oral toxicity of greater than

5 mg/kg but less than or equal to 50 mg/kg is mailable only between

authorized parties under the specific conditions in

346.231b.

Proper Shipping Name

 Various (see Appendix A).

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only between authorized parties via air

transportation or surface transportation.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 361

Authorized Mailers

Toxic substances that have an LD

for oral toxicity of greater than 5 mg/kg

but less than or equal to 50 mg/kg may be mailed between the following

parties subject to these specific conditions:

 Toxic substances for scientific use (not outwardly or of their own force

dangerous or injurious to life, health, or property) may be sent only

between manufacturers, dealers, bona fide research or experimental

scientific laboratories, and employees of federal, state, or local

governments who have official use for such poisons and are

designated by the agency head to receive or send such poisons.

 Poisonous drugs and medicines that are regulated as Division 6.1

materials may be sent only from the manufacturer or dealer of the

drugs and medicines to licensed physicians, surgeons, dentists,

pharmacists, druggists, cosmetologists, barbers, and veterinarians

(18

U.S.C. 1716).

Note: Drugs and medicines that are not regulated as Division 6.1

materials are subject to the conditions in Chapter

Required Packaging

Primary Receptacle

 The total volume in the primary receptacle must not exceed 8 ounces.

 The primary receptacle must be leak-resistant and have a secure

method of closure.

Absorbent and Cushioning Material

 Each primary receptacle that contains a liquid material must be

completely surrounded by absorbent material capable of completely

taking up all the contents in the event of breakage.

 Sufficient cushioning material must surround the primary receptacle(s)

to absorb shocks and prevent damage.

Secondary Container

 For toxic liquids the secondary container must be leakproof.

 For toxic solids the secondary container must be siftproof.

 The primary receptacle, absorbent material, and cushioning material

must fit firmly and securely within the secondary packaging to absorb

shocks and prevent breakage during normal postal handling.

Outer Shipping Container

 The outer container must be constructed of 200-pound grade

corrugated fiberboard or equivalent strength.

 The secondary container must fit firmly and securely within the outer

shipping container packaging to prevent breakage during normal

postal handling.

Appendix C Hazardous, Restricted, and Perishable Mail

362 Publication 52

Marking

 The proper shipping name and UN number of the toxic material must

be clearly marked on the address of the mailpiece.

 Orientation markings (see Exhibit 226) that properly indicate the upright

position of the primary receptacle(s) must be displayed on two

opposite outer side walls of the outer shipping container.

 Each mailpiece must bear a complete return address and delivery

address. The delivery address must be placed on the top side of the

mailpiece.

Documentation

 For air or surface transportation, a properly completed shipper's

declaration for dangerous goods (i.e., shipping paper) must be

prepared in triplicate and affixed to the outside of the mailpiece.

USPS Packaging Instruction 6C

Category B Infectious Substances

Infectious substance means a material known or reasonably expected to

contain a pathogen. A pathogen is a microorganism that can cause disease

in humans or animals. Examples of pathogens include bacteria, viruses,

fungi, and other infectious agents. An infectious substance must be assigned

to one of the following two packaging categories:

 Category A: Category A infectious substances are not mailable.

 Category B: An infectious substance that does not meet the criteria for

inclusion in Category A. A mailpiece known or suspected to contain a

Category B infectious substance is mailable as described in

346.

Proper Shipping Name and ID Number

 Biological substance, Category B, UN3373.

Required Authorization

All vendors shipping COVID-19-related UN3373 Category B Infectious

Substances kits to end-users must obtain an authorization from the Postal

Service before mailing. The shipper has the responsibility to ensure

awareness of, and compliance with, all other applicable requirements and

regulations for mailing these materials. The shipper must be able to provide

evidence of compliance before submitting a written request to the director of

Product Classification, Postal Service Headquarters (see part

214 for

address).

Under these provisions, only tests developed and performed by laboratories

certified under the Clinical Laboratory Improvement Amendments (CLIA) or

equivalent clinical oversight regulations, and commercial tests and home

collection kits authorized by either the FDA or an Institutional Review Board,

will be considered.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 363

Mailability

 International Mail: Mailable only when:

– Permitted by the destination country (see the Individual Country

Listing in the IMM).

– They are presented by and to authorized laboratories designated in

“International Mail” below in this Packaging Instruction.

– They meet the definition in 346.12a.

– The director, Product Classification, has granted written approval.

– Quantity limits in 622.2 are met.

– Sent via First-Class Package International Service with Registered

Mail service.

 Domestic Mail: Mailable only when:

– Intended for medical or veterinary use, research, or laboratory

certification related to the public health.

– Division 6.2 materials meet the preparation requirements for air

transportation and are sent via Priority Mail Express or Priority Mail.

Required Packaging

 Must be triple-packaged, meeting the packaging requirements in

CFR 173.199. Such materials must be properly packaged to

withstand shocks, pressure changes, and other conditions related to

ordinary handling in transit, and surrounded by absorbent material

sufficient to protect the primary receptacle and to absorb the total

amount of liquid should the primary receptacle leak or break.

 The completed triple packaging must be capable of successfully

passing the drop test in 49 CFR

§178.609(d) at a drop height of at least

1.2 meters (3.9 feet). Following the drop test, there must be no leakage

from the primary receptacle, which must remain protected by

absorbent material, when required, in the secondary packaging.

Primary Receptacle (Container)

 Each primary receptacle containing a liquid must be leakproof. Each

primary receptacle containing a solid must be siftproof.

 A single primary receptacle must not contain more than 1 liter

(34

ounces) of a liquid specimen or 4 kg (8.8 pounds) of a solid

specimen.

 Two or more primary receptacles whose combined volume does not

exceed 4 liters (1 gallon) for liquids or 4

kg (8.8 pounds) for solids may

be enclosed in a single secondary container.

 Only small quantities of Class 3, Class 8, Class 9, or other materials in

Packing Groups II and III may be used to stabilize or prevent

degradation of the sample, provided the quantity of such materials

does not exceed 30 mL (1 ounce) or 30 g (1 ounce) in each inner

packaging.

Appendix C Hazardous, Restricted, and Perishable Mail

364 Publication 52

Cushioning and Absorbent Material

 The space between the primary receptacle(s) and the secondary

container at the top, bottom, and sides must contain enough material

to absorb the entire contents of the primary receptacle(s) in case of

breakage or leakage.

 Either the primary receptacle or the secondary container must be

capable of withstanding, without leakage, an internal pressure that

produces a pressure differential of not less than 0.95 bar, 14 psi

(95

kPa), and temperatures in the range of –40° F to 131° F (–40° C to

55° C).

Secondary Container

 Secondary containers for liquids must be leakproof. Secondary

containers for solids must be siftproof. The secondary packaging must

be constructed of a durable material and have a secure sealing

method.

 If the primary receptacle does not meet the pressure requirements

listed above, then the secondary container must be designed to meet

those requirements.

 The secondary container must be marked with the international

biohazard symbol shown in

Exhibit 346.321.

Note: Only cold packs or dry ice may be used as a refrigerant and must

be placed outside of the secondary packaging. Interior supports must be

provided to secure the secondary packaging in the original position. If a

cold pack is used, the packaging must be leak-proof. If dry ice is used,

the container must permit the release of carbon dioxide gas and conform

to 49 CFR 173.217. The primary receptacle and secondary packaging

must maintain their integrity at the temperature of the refrigerant used, as

well as the temperature and pressures of transport by aircraft they could

be subjected to if refrigerant were lost, and sufficient absorbent material

must be provided to absorb all liquids, including melted ice.

Outer Shipping Container

 The primary and secondary packaging must be enclosed in a rigid

outer shipping container. The primary receptacle(s) and the secondary

container must be enclosed in a strong outer packaging constructed of

fiberboard or other equivalent material.

 At least one surface of the outer shipping container must have a

minimum dimension of 3.9 inches by 3.9 inches (100 mm by 100 mm)

as required by 49 CFR 173.199. The outer packaging must be of

adequate size to accommodate all required shipping information and

marks.

 A poly-type mailer bag covering may be acceptable as the outer

packaging provided triple packaging is complete, the selvage edge of

the wrapping is less than 2 inches, and the required markings and

address information are applied both on the interior rigid box and the

additional outer polybag wrapping.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 365

Markings

As required by 49 CFR 173.199:

 Each mailpiece (outer shipping container) must be marked on the

address side with the proper shipping name “Biological Substance,

Category B” and have the diamond marking indicating UN3373

(see

Exhibit 346.12a2). The size of the mark on each side must not be

less than 50 mm (1.97 inches) in length, the width of the border lines

must be at least 2 mm, and letter and numbers must be at least 6 mm

(0.24 inches) high.

 The address side of the outer shipping container must be marked with

name and telephone number of a person who is knowledgeable about

the material shipped and has comprehensive emergency response and

incident mitigation information, or someone who has immediate access

to the person with such knowledge and information.

 Orientation arrows are not required on these mailpieces but may be

used.

 When dry ice is used, the package must include the markings “Carbon

dioxide, solid” or “Dry ice,” and an indication that the material being

refrigerated is used for diagnostic or treatment purposes (e.g., frozen

medical specimens). As this is the only information required with

respect to global transportation regulations for dry ice included with

UN3373 shipments, the requirements for dry ice as set forth in USPS

Packaging Instruction 9A are not applicable.

Documentation

Each vendor shipping COVID-19 kits must provide clear instructions to end-

users regarding the procedures to be followed for preparing the samples and

packaging used to transport an Infectious Substance Category B. Shippers

must instruct end-users to adhere to all applicable mail-related preparation

requirements before mailing to ensure the package is properly prepared for

safe transportation.

International Mail

 Substances identified in IMM 135.11b must be sent only by authorized

laboratories to their foreign counterparts in those countries that have

indicated a willingness to accept them.

Note: Countries distinguish between infectious and noninfectious

(nonregulated) biological substances and may prohibit one or the other

or both. See “Prohibitions” in the Individual Country Listings.

 Infectious biological substances can be sent to or received by only the

following types of institutions:

a. Laboratories of local, state, and federal government agencies.

b. Laboratories of federally licensed manufacturers of biological

products derived from bacteria and viruses.

c. Laboratories affiliated with or operated by hospitals, universities,

research facilities, and other teaching institutions.

d. Private laboratories licensed, certified, recognized, or approved

by a public authority.

Appendix C Hazardous, Restricted, and Perishable Mail

366 Publication 52

USPS Packaging Instruction 6D

Sharps Waste and Other Regulated Medical Waste

Regulated medical waste and sharps medical waste known or suspected to

contain a Category A infectious substance is not mailable. Regulated

medical waste and sharps medical waste as defined in

346.12f and 346.12g

and containing materials classified as Category B infectious substances are

permitted for mailing provided that all applicable requirements specified in

346.322 are met.

For packaging instructions for medical professional packages, refer to

346.322b–d.

Proper Shipping Name and ID Number

 Regulated Medical Waste, UN3291.

 Sharps Medical Waste, UN3291.

Required Authorization

 Each vendor of a complete regulated medical waste or sharps waste

mailing container system (including all component parts required to

safely mail such waste to a storage or disposal facility) must obtain

authorization from the Postal Service prior to mailing. The vendor in

whose name the authorization is being sought must submit a written

request to the director of Product Classification, Postal Service

Headquarters (see

214 for address).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted only using USPS Returns Service via Priority

Mail Return Service option.

Required Packaging

General

 Only regulated medical waste and sharps medical waste mailing

container systems approved by Postal Service Headquarters may be

mailed. Approved packaging must meet all requirements in

346.322b,

including a leakproof primary receptacle (also puncture-resistant for

sharps medical waste), a water-resistant secondary containment

system, enough material within the primary receptacle to absorb and

retain three times the total liquid allowed within the primary receptacle,

and a step-by-step instruction sheet that details the sequence and

method of container assembly prior to mailing.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 367

Marking

 Each primary receptacle and outer shipping container must bear a

label, which cannot be detached intact, showing the name of the

vendor, the USPS Authorization Number, and the container ID number.

Place the label on the top or on a side of the container.

 The primary receptacle(s) and the outer shipping container must bear

the international biohazard symbol in black with either a fluorescent

orange or fluorescent red background as shown in

Exhibit 346.321.

The symbol on the outer shipping container must be at least 3 inches

high and 4 inches wide.

 The outer shipping container must bear a properly prepared USPS

Returns Service label. The USPS Returns Service permit must be held

in the same name as that of the authorized medical waste vendor.

 The outer shipping container must be marked on two opposite side

walls with the package orientation marking in 49 CFR 173.312 to

identify the proper upright position of the mailpiece during handling.

 Mailpieces containing regulated medical waste or sharps waste must

be marked on the address side with the correct UN number and proper

shipping name (e.g., “Regulated Medical Waste, UN3291” or

“Regulated Medical Waste-Sharps, UN3291”).

Documentation

 Each mailpiece must have a four-part waste shipping paper. The

shipping paper must be affixed to the outside of the mailpiece in an

envelope or similar carrier that can be easily opened and resealed to

allow review of the document. The shipping paper must comply with all

applicable requirements imposed by the laws of the state from which

the container system is mailed. At a minimum, the information in

Exhibit 346.322c3 must be on the shipping paper.

USPS Packaging Instruction 6E

Used Health Care Products

“Used health care product” means a medical, diagnostic, or research device

or piece of equipment, or a personal care product used by consumers,

medical professionals, or pharmaceutical providers, that does not meet the

definition of a diagnostic specimen, biological product, regulated medical

waste, or sharps waste, is contaminated with potentially infectious body

fluids or materials, and is not decontaminated or disinfected to remove or

mitigate the infectious hazard prior to transport.

Proper Shipping Name

 Not applicable.

Appendix C Hazardous, Restricted, and Perishable Mail

368 Publication 52

Mailability

 International Mail: Prohibited.

 Domestic Mail: A used health care product:

– Known or reasonably suspected to contain a Category A material

is not mailable.

– Not suspected to contain infectious material or that is known, or

suspected, to contain Category B infectious substances, and is

being returned to the manufacturer or manufacturer's designee, is

mailable with air transportation.

Required Packaging

 Each used health care product must be drained of liquid to the extent

possible and placed in a watertight primary receptacle designed and

constructed to ensure that it remains intact under normal conditions of

transport. For a used health care product capable of cutting or

penetrating skin or packaging material, the primary receptacle must be

capable of retaining the product without puncture of the packaging

under normal conditions of transport.

Primary Container

 The primary receptacle must be capable of retaining the product

without puncture of the packaging under normal conditions of

transport.

 Each primary receptacle must be placed inside a watertight secondary

container designed and constructed to ensure that it remains intact

under normal conditions of transport.

 The primary receptacle must be marked with the international

biohazard symbol shown in

Exhibit 346.321.

Secondary Container

 Each primary receptacle must be placed inside a watertight secondary

container designed and constructed to ensure that it remains intact

under normal conditions of transport.

 The secondary container must also be marked with the international

biohazard symbol shown in

Exhibit 346.321.

Outer Shipping Container

 The secondary container must be placed inside an outer shipping

container with sufficient cushioning material to prevent movement

between the secondary container and the outer shipping container. An

itemized list of the contents of the primary receptacle and information

concerning possible contamination with a Division 6.2 material,

including its possible location on the product, must be placed between

the secondary container and the outer shipping container.

Marking/Documentation

 A shipping paper and content marking on the outer shipping container

are not required.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 369

USPS Packaging Instruction 6F

Forensic Material

Forensic material containing a biological material, such as tissue, body fluid,

excreta, or secreta, and sent on behalf of a federal, state, local, or Indian

tribal government agency must be packaged under

346.325 when it is not

known or suspected to contain a Category A or Category B infectious

substance. Forensic material known or suspected to contain a Category A

infectious substance is not mailable. Forensic material known or suspected

to contain a Category B infectious substance as identified in

346.321 is

mailable via air transportation, when triple-packaged in a primary receptacle,

secondary container, and a rigid outer shipping container.

Proper Shipping Name

 Not applicable.

Mailability

 International Mail: Mailable only when:

– Permitted by the destination country (see the Individual Country

Listing in the IMM).

– They are presented by and to authorized laboratories designated in

“International Mail” below in this Packaging Instruction.

– They meet the Category B infectious substance definition in

346.12a.

– The director, Product Classification, has granted written approval.

– Quantity limits in 622.2 are met.

– They are triple-packaged (see below), meeting the packaging

requirements in 49 CFR 173.199.

– Sent via First-Class Package International Service with Registered

Mail service.

 Domestic Mail: Mailable only when:

– Intended for medical or veterinary use, research, or laboratory

certification related to the public health.

– Division 6.2 materials meet the preparation requirements for air

transportation and are sent via Priority Mail Express or Priority Mail.

Required Packaging

 Must be triple-packaged, meeting the packaging requirements in

CFR 173.199. Such materials must be properly packaged to

withstand shocks, pressure changes, and other conditions related to

ordinary handling in transit, and surrounded by absorbent material

sufficient to protect the primary receptacle and to absorb the total

amount of liquid should the primary receptacle leak or break.

Appendix C Hazardous, Restricted, and Perishable Mail

370 Publication 52

Primary Receptacle (Container)

 Each primary receptacle containing a liquid must be leakproof. Each

primary receptacle containing a solid must be siftproof.

 A single primary receptacle must not contain more than 1 liter

(34

ounces) of a liquid specimen or 4 kg (8.8 pounds) of a solid

specimen.

 Two or more primary receptacles whose combined volume does not

exceed 4

liters (1 gallon) for liquids or 4 kg (8.8 pounds) for solids may

be enclosed in a single secondary container.

Cushioning and Absorbent Material

 The space between the primary receptacle(s) and the secondary

container at the top, bottom, and sides must contain enough material

to absorb the entire contents of the primary receptacle(s) in case of

breakage or leakage.

 Either the primary receptacle or the secondary container must be

capable of withstanding, without leakage, an internal pressure that

produces a pressure differential of not less than 0.95 bar, 14 psi

(95

kPa), and temperatures in the range of –40° F to 131° F (–40° C to

55°

C).

Secondary Container

 Secondary containers for liquids must be leakproof. Secondary

containers for solids must be siftproof. The secondary packaging must

be constructed of a durable material and have a secure sealing

method.

 If the primary receptacle does not meet the pressure requirements

listed above, then the secondary container must be designed to meet

those requirements.

 The secondary container must be marked with the international

biohazard symbol shown in

Exhibit 346.321.

Outer Shipping Container

 The primary and secondary packaging must be enclosed in a rigid

outer shipping container. The primary receptacle(s) and the secondary

container must be enclosed in a strong outer packaging constructed of

fiberboard or other equivalent material.

 At least one surface of the outer shipping container must have a

minimum dimension of 3.9 inches by 3.9 inches (100 mm by 100 mm)

as required by 49 CFR 173.199.

Marking/Documentation

 Category B infectious substances not present:

– A shipping paper and content markings on the outer shipping

container are not required.

– Each mailpiece must have a complete delivery and return address.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 371

 Category B infectious substances are present:

– Each mailpiece (outer shipping container) must be marked with the

proper shipping name “Biological Substance, Category B” and

have the diamond marking indicating UN3373 (see

Exhibit

346.12a2).

– The address side of the outer shipping container must be marked

with name and telephone number of a person who is

knowledgeable about the material shipped and has comprehensive

emergency response and incident mitigation information, or

someone who has immediate access to the person with such

knowledge and information.

– Orientation arrows are not required on these mailpieces but may

be used.

International Mail

Substances identified in IMM 135.11b must be sent only by authorized

laboratories to their foreign counterparts in those countries that have

indicated a willingness to accept them.

Note: Countries distinguish between infectious and noninfectious

(nonregulated) biological substances and may prohibit one or the other

or both. See “Prohibitions” in the Individual Country Listings.

 Infectious biological substances can be sent to or received by only the

following types of institutions:

– Laboratories of local, state, and federal government agencies.

– Laboratories of federally licensed manufacturers of biological

products derived from bacteria and viruses.

– Laboratories affiliated with or operated by hospitals, universities,

research facilities, and other teaching institutions.

– Private laboratories licensed, certified, recognized, or approved by

a public authority.

USPS Packaging Instruction 6G

Nonregulated Infectious Materials

Nonregulated materials as defined in 346.234 are not subject to regulation as

hazardous materials but must be properly packaged when presented for

mailing. Nonregulated materials include biological product, blood collected

for the purpose of blood transfusion, blood products and blood components

collected for the purpose of transfusion, dried blood spots, forensic material

not expected of containing a Category A or Category B infectious substance

and transported on behalf of a government agency. For a complete

description of nonregulated materials, see

346.234.

Proper Shipping Name and ID Number

 Not applicable (not regulated under 49 CFR as a hazardous material in

domestic commerce).

Appendix C Hazardous, Restricted, and Perishable Mail

372 Publication 52

Mailability

 International Mail: Nonregulated materials identified in 346.234 are

mailable but must be properly packaged as indicated in 346.325 when

presented for mailing.

 Domestic Mail: Permitted via air or surface transportation when

packaging requirements are met.

Required Packaging

Liquid Patient Specimens and Biological Products

Exceeding 50 ml

 Material must be packaged in a securely sealed primary receptacle. A

single primary receptacle must not contain more than 500

ml of

specimen. Two or more primary receptacles whose combined volume

does not exceed 500 ml may be enclosed in a single secondary

container. The secondary container must be securely and snugly

enclosed in a fiberboard box or container of equivalent strength that

serves as the outer shipping container.

Not Exceeding 50 ml

 A patient specimen or biological product consisting of 50 ml or less per

mailpiece must be packaged in a securely sealed primary receptacle.

Two or more primary receptacles whose combined volume does not

exceed 50 ml may be enclosed within a single mailpiece. The

secondary container can also serve as the outer shipping container. In

that case, the biohazard symbol must appear on the inner packaging or

on the primary container.

Absorbent and Cushioning Material

 Sufficient absorbent material and cushioning material to withstand

shock and pressure changes must surround the primary receptacle(s),

or be otherwise configured to take up the entire liquid contents in case

of leakage.

Secondary Container

 The secondary container must be securely sealed, and it may serve as

the outer shipping container if it has sufficient strength to withstand

ordinary postal processing.

 The primary receptacle(s) and the absorbent cushioning must be

enclosed in a secondary container with a leakproof barrier that can

prevent failure of the secondary container if the primary receptacle(s)

should leak during transport.

 The secondary container must be marked with the international

biohazard symbol shown in

Exhibit 346.321, except when the

secondary container also serves as the outer shipping container. In

that case, the biohazard symbol must appear on the inner packaging or

on the primary container.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 373

Outer Shipping Container

 A fiberboard box or container of equivalent strength that serves as the

outer shipping container.

 When the secondary container also serves as the outer shipping

container, the biohazard symbol must appear on the inner packaging

or on the primary container.

Solid or Dry Specimen

Primary Receptacle

 The primary receptacle (and cushioning material, if required) must be

enclosed in a secondary container.

Secondary Container

 The secondary container must be siftproof to contain the contents

should the primary receptacle(s) leak.

 The secondary container must be marked with the international

biohazard symbol (see

Exhibit 346.321).

Outer Shipping Container

 The secondary container may serve as the outer shipping container if it

has sufficient strength to withstand ordinary postal processing.

Markings

 A complete return address and delivery address must be used.

 No other identifying marks are allowed on the outside of the box.

Note: A shipper's declaration for dangerous goods (shipping papers) is

not required for clinical specimens that do not contain infectious

substances.

USPS Packaging Instruction 6H

Exempt Human or Animal Specimens

Exempt human or animal specimens as defined in 346.12d are not subject to

regulation as hazardous materials, but when presented for mailing, they must

be properly packaged. See

346.326.

“Exempt human or animal specimen” means a human or animal sample

(including, but not limited to, secreta, excreta, blood and its components,

tissue and tissue fluids, and body parts) transported for routine testing not

related to the diagnosis of an infectious disease.

Typically, exempt human specimens are specimens for which there is a low

probability that the sample is infectious, such as specimens for drug or

alcohol testing; cholesterol testing; blood glucose level testing; prostate-

specific antigens (PSA) testing; testing to monitor heart, kidney, or liver

function; pregnancy testing; and testing for diagnosis of noninfectious

diseases such as cancer biopsies.

Proper Shipping Name

 Not applicable (not regulated under 49 CFR as a hazardous material in

domestic commerce).

Appendix C Hazardous, Restricted, and Perishable Mail

374 Publication 52

Mailability

 International Mail: Mailable. They are not subject to regulation as

hazardous materials, but when presented for mailing, they must be

packaged as identified in

346.326.

 Domestic Mail: Permitted via air or surface transportation when

packaging requirements are met.

Required Packaging

Primary Receptacle

 Material must be triple-packaged in leakproof (for liquids) or siftproof

(for solids) primary receptacles.

 A single primary receptacle must not contain more than 500 ml of a

liquid specimen or 500 grams of a solid specimen.

 Two or more primary receptacles whose combined volume does not

exceed 500 ml (for liquids) or 500 grams (for solids) may be enclosed in

a single secondary container.

 Sufficient cushioning and absorbent materials must surround each

primary receptacle containing liquid.

Secondary Container

 The secondary container cannot serve as the outer shipping container.

 The secondary container must be securely and snugly enclosed in a

fiberboard box or container of equivalent strength that serves as the

outer shipping container. The outer shipping container must be rigid.

 The secondary container must be marked with the international

biohazard symbol shown in

Exhibit 346.321.

Marking/Documentation

 The outer shipping container must be marked on the address side with

the words “Exempt human specimen” or “Exempt animal specimen,”

as appropriate. In addition, at least one surface of the outer packaging

must have a minimum dimension of 3.9 inches by 3.9 inches (100 mm

by 100 mm).

 A shipping paper is not required.

USPS Packaging Instruction 7A

Radioactive Materials

Radioactive materials are prohibited in international mail and domestic mail if

required to bear the DOT Radioactive White-I, Radioactive Yellow-II,

Radioactive Yellow-III label, or the Fissile label (49 CFR 172.436, 172.438, or

172.440, respectively) or if it contains quantities of radioactive material in

excess of those authorized in

347. Radioactive materials are prohibited in

domestic mail via air transportation. For international mail, the standards in

IMM 135.5 apply.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 375

The only categories of radioactive material that are mailable are those that

can be classified as a “limited quantity” under 49 CFR and that meet the

limits in

Exhibit 347.22: excepted instruments, articles, and devices, and

excepted articles containing natural uranium and thorium. Accurate

documentation of the activity limits, which must not exceed those specified

Exhibit 347.22, must be provided.

Proper Shipping Name and ID Number

 Radioactive Material, excepted package-limited quantity, UN2910.

 Radioactive Material, excepted package-instruments or articles,

UN2911.

 Radioactive Material, excepted package-articles manufactured from

natural uranium (or natural thorium), UN2909.

Mailability

 International Mail: Only as permitted in 622.3 and IMM 135.5, and when

sent with under the following conditions:

– Sent only to those countries that have expressed a willingness to

accept them (see the Individual Country Listings in the IMM).

– Each radioactive materials shipment must be sent via First-Class

Package International Service using Registered Mail service.

– Mailable radioactive materials may not have an activity content that

exceeds one-tenth of the limits in

Exhibit 347.22

– Each shipment must comply with both the International Atomic

Energy Agency Regulations and the specifications contained in

347 and this section.

– The sender and recipient of each radioactive materials shipment

must receive prior authorization from the appropriate regulatory

authorities within their countries.

– A white package label bearing the French words “Matieres

Radioactives” (Radioactive Materials) must be securely affixed,

taped, or gummed to the address side of each mailpiece

containing radioactive materials. The sender is responsible for

supplying and affixing this label to the mailpiece.

– The address side of each mailpiece must bear the following

endorsements in bold letters: “Return to Sender in Case of

Nondelivery” and “Radioactive Materials, Quantities Permitted for

Movement by Post.”

– A shipper’s declaration for dangerous goods is required. See 326

and 725.3.

 Domestic Mail: Permitted only via surface transportation and when the

applicable requirements in

347 are met.

Required Packaging

Separate packaging requirements apply as follows.

 Domestic Mail for Limited Quantities (49 CFR 173.421) whose activity

per package does not exceed the limits specified in

Exhibit 347.22:

Appendix C Hazardous, Restricted, and Perishable Mail

376 Publication 52

– Primary Receptacle:

 The materials are packaged in strong, tight inner receptacles

that will not leak any of the radioactive materials during normal

Postal Service handling.

– Absorbent and Cushioning Material:

 Sufficient and suitably positioned absorbent material capable

of absorbing at least twice the volume of the liquid contents in

the event of leakage is required.

 Adequate cushioning material to withstand shock and pressure

changes must surround the primary receptacle.

– Secondary Packaging:

 Liquid radioactive materials must be packaged within a

leak-resistant and corrosion-resistant secondary packaging.

– Outer Packaging:

 The inner receptacle and the secondary packaging (when

required) must be securely packed within a strong outer

packaging.

 The radiation level at any point on the external surface of the

mailpiece must not exceed 0.5 millirem per hour.

 The nonfixed (removable) radioactive surface contamination on

the external surface of the mailpiece does not exceed the

applicable limits specified in 49 CFR 173.443(a).

 The package does not contain fissile material unless excepted

by 49

CFR 173.453.

 No single dimension of the external mailpiece can be less than

2.5

centimeters (1 inch), and the length and girth can be no

less than 30

centimeters (12 inches).

–Marking:

 The outside of the inner receptacle or the outside of the

secondary packaging must be clearly marked “Radioactive.”

 The address side of the mailpiece must clearly display the

following marking: “This package conforms to the conditions

and limitations specified in 49 CFR 173.421 for radioactive

material, excepted package-limited quantity of material,

UN2910 and is within Postal Service activity limits for mailing.”

 A complete return address and delivery address must be used.

 Domestic Mail for Mailable Instruments and Articles (49 CFR 173.424)

permitted under

347:

Instruments and manufactured articles (including clocks, electronic

tubes, or apparatus) or similar devices having radioactive materials in

gaseous or nondispersible solid form as a component part must be

packed as follows:

– Primary Receptacle:

 The activity of the instrument or device must not exceed the

relevant limit listed in

Exhibit 347.22.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 377

 The radiation level at 10 centimeters (4 inches) from any point

on the external surface of the unpackaged instrument or

device must not exceed 10 millirem per hour.

– Cushioning Material:

 Adequate cushioning material to withstand shock and pressure

changes must surround the primary receptacle.

– Outer Packaging:

 The inner receptacle and cushioning material must be securely

packed within a strong outer packaging.

 The total activity per mailpiece must not exceed the relevant

limit listed in

Exhibit 347.22.

 The radiation level at any point on the external surface of the

mailpiece containing the device or instrument must not exceed

0.5 millirem per hour.

 The nonfixed (removable) radioactive surface contamination on

the external surface of the mailpiece must not exceed the

applicable limits specified in 49 CFR 173.443(a).

 The package does not contain fissile material unless excepted

by 49

CFR 173.453.

 At least one external dimension of the mailpiece must be no

less than 10 centimeters (4 inches).

–Marking:

 The outside of the inner receptacle or the outside of the

secondary packaging must be clearly marked “Radioactive.”

 The address side of the mailpiece must clearly display the

following marking: “This package conforms to the conditions

and limitations specified in 49 CFR 173.424 for radioactive

material, excepted package-instruments or articles, UN2911

and is within Postal Service activity limits for mailing.”

 A complete return address and delivery address must be used.

 Domestic Mail for Mailable Excepted Articles Containing Uranium or

Thorium (49 CFR 173.426) permitted under

347:

Manufactured articles excepted under 347 and in which the sole

radioactive material is natural or depleted uranium or natural thorium

must be packaged as follows:

– Primary Receptacle:

 The outer surface of the uranium or thorium is enclosed in an

inactive sheath made of metal or other durable protective

material.

– Cushioning Material:

 Adequate cushioning material to withstand shock and pressure

changes must surround the primary receptacle.

– Outer Packaging:

 The inner receptacle and cushioning material must be securely

packed within a strong outer packaging.

Appendix C Hazardous, Restricted, and Perishable Mail

378 Publication 52

 The radiation level at any point on the external surface of the

mailpiece must not exceed 0.5 millirem per hour.

 The nonfixed (removable) radioactive surface contamination on

the external surface of the mailpiece must not exceed the

applicable limits specified in 49 CFR 173.443(a).

–Marking:

 The outside of the inner receptacle or the outside of the

secondary packaging must be clearly marked “Radioactive.”

 The address side of the mailpiece must clearly display the

following marking: “This package conforms to the conditions

and limitations specified in 49 CFR 173.426 for radioactive

material, excepted package-articles manufactured from natural

uranium (or natural thorium), UN2909 and is within Postal

Service activity limits for mailing.”

 A complete return address and delivery address is required.

Note: A shipper's declaration for dangerous goods is not required for

mailable radioactive materials.

 International Mail:

The requirements specified in 622.3 and IMM 135.5 apply in addition to

the packaging instructions for domestic mail.

USPS Packaging Instruction 8A

Corrosives

A corrosive is any liquid or solid that causes visible destruction or irreversible

alteration in human skin tissue at the site of contact or a liquid that has a

severe corrosion rate on steel or aluminum.

A Class 8 corrosive material that qualifies as a Limited Quantity air or Limited

Quantity surface material is permitted via air or surface transportation in

domestic mail provided that all applicable requirements in

348 are met.

Proper Shipping Name

 Various (see Appendix A).

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via air or surface transportation when

packaging requirements are met.

Required Packaging

Separate packaging requirements apply for liquids and solids.

 For Mailable Liquid Corrosives:

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 379

– General:

 Liquid Corrosive. A liquid mixture must be 1 pint (16 ounces) or

less, and must contain 15 percent or less corrosive material

with the remainder of the mixture not being a hazardous

material, unless otherwise specified for a specific corrosive

material.

– Primary Receptacles:

 Primary receptacles must be securely sealed compatible glass

bottles.

 The primary receptacle must be tightly sealed with a screw cap

having a minimum of one-and-one-half turns, a soldering clip,

or other means to effect secure closure. A friction-top closure

is not acceptable.

 Volume per primary receptacle is limited to 16 ounces.

 Multiple primary receptacles are permitted.

– Absorbent and Cushioning Material:

 A noncombustible absorbent material that is capable of taking

up all liquid in case of leakage must surround the primary

receptacle.

 Cushioning material must surround the primary receptacle to

prevent breakage.

– Secondary Packaging:

 The secondary packaging container must be constructed of

metal or plastic and be compatible with the design of the

primary receptacle.

 The secondary container must be tightly sealed with a screw

cap having a minimum of one-and-one-half turns, a soldering

clip, or other means to effect secure closure. A friction-top

closure is not acceptable.

– Outer Shipping Container:

 The primary receptacle, absorbent material, cushioning

material, and secondary packaging must be packed in a strong

outer packaging.

 Each mailpiece must not exceed a total weight of 25 pounds.

–Marking:

The following labels and text markings must be placed on the

address side of the mailpiece unless specified in

221.1 and

325.1.

 For air transportation, mailpieces must bear the DOT Limited

Quantity air mark (with the symbol “Y” in the center), an

approved DOT Class 8 hazardous material warning label, the

identification number and the proper shipping name

 For surface transportation, the outer packaging must bear an

approved DOT Limited Quantity surface mark designating

surface transportation, prepared under

348.4b.

Appendix C Hazardous, Restricted, and Perishable Mail

380 Publication 52

 A complete return and delivery address must be used.

– Documentation:

 For air transportation, a properly completed shipper's

declaration for dangerous goods must be prepared in triplicate

and affixed to the outside of the mailpiece.

 For Mailable Solid Corrosives:

– General:

 A solid mixture must be 10 pounds or less per primary

receptacle and must contain 10 percent or less corrosive

material with the remainder of the mixture not being a

hazardous material, unless otherwise specified for a specific

corrosive solid.

– Primary Receptacle:

 Each primary receptacle must be siftproof and be securely

sealed.

– Secondary Packaging:

 Each primary receptacle must be packed within a siftproof

secondary packaging container that is compatible with the

primary receptacle.

– Outer Packaging:

 The primary receptacle and the compatible secondary

packaging containers must be snugly packed within a strong

outer packaging.

 Multiple primary receptacles and compatible secondary

packaging containers may be packed within a single outer

packaging up to a total weight of 25 pounds per mailpiece.

–Marking:

The following labels and text markings must be placed on the

address side of the mailpiece unless specified in

221.1 and

325.1.

 For air transportation, mailpieces must bear the DOT Limited

Quantity air mark (with the symbol “Y” in the center), an

approved DOT Class 8 hazardous material warning label, the

identification number, and the proper shipping name

 For surface transportation, the outer packaging must bear an

approved DOT Limited Quantity surface mark designating

surface transportation, prepared under

348.4b.

 A complete return and delivery address must be used.

– Documentation:

 For air transportation, a properly completed shipper's

declaration for dangerous goods must be prepared in triplicate

and affixed to the outside of the mailpiece.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 381

USPS Packaging Instruction 8B

Nonspillable Wet Battery

A nonspillable wet battery containing liquid electrolyte is prohibited from

mailing unless the battery casing is completely sealed to prevent the liquid

corrosive from spilling during handling, as allowed in

348. Nonspillable

batteries with UN2800 are prohibited in international mail, but they may be

sent as domestic mail via air or surface transportation when properly

packaged. Nonspillable wet batteries mailed in accordance with these

instructions must meet all applicable conditions in 49 CFR 173.159a.

Proper Shipping Name

 Nonspillable Battery.

ID Number

 UN2800.

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via air or surface transportation when

packaging requirements are met.

Required Packaging

Primary Receptacle

 The nonspillable battery must be capable of withstanding the vibration

and pressure differential tests cited in 49 CFR 173.159(f) (1) and (2).

Absorbent and Cushioning Material

 The nonspillable battery must be protected from short circuits with

protective or cushioning material.

 A noncombustible material that is capable of absorbing all liquid in

case of leakage must surround the primary receptacle.

Outer Packaging

 The nonspillable battery must be securely packaged in a strong

fiberboard box.

 Only one nonspillable battery is allowed per mailpiece.

 The total weight of a single mailpiece cannot exceed 25 pounds.

Marking

 The outer packaging must be plainly and durably marked on the

address with the text “NONSPILLABLE BATTERY, UN2800.”

 Each mailpiece must include the mailer and addressee names and

have a complete delivery and return address.

Note: A shipper's declaration for dangerous goods is not required for

nonspillable wet batteries sent via air transportation as exempted in

CFR 173.159a.

Appendix C Hazardous, Restricted, and Perishable Mail

382 Publication 52

USPS Packaging Instruction 8C

Manufactured Devices that Contain Small Amounts

of Mercury

A corrosive is any liquid or solid that causes visible destruction or irreversible

alteration in human skin tissue at the site of contact or a liquid that has a

severe corrosion rate on steel or aluminum.

A Class 8 manufactured article that contains minute amounts of mercury

(such as compact fluorescent lamps [CFLs]) that meets the standards below

is permitted in domestic mail provided all the applicable requirements in

348.22g are met.

Proper Shipping Name

 Mercury contained in manufactured articles

ID Number

 UN3506

Mailability

 International Mail. Prohibited

 Domestic Mail: Permitted via air or surface transportation when

packaging requirements are met.

Required Packaging

Primary Receptacle

 Each primary device, article, or apparatus must be a securely sealed

glass, or equivalent material, enclosure.

 Each device, article, or apparatus must be cushioned and separated

from other items and must not exceed 100 milligrams (mg) (0.0035

ounce) of mercury.

 Multiple devices are permitted within a single mailpiece, provided the

aggregate mercury quantity does not exceed 1 gram (g) (0.035 ounce)

of mercury within the mailpiece.

Absorbent and Cushioning Material

A noncombustible absorbent/cushioning material, capable of containing any

leakage in case of breakage, must surround each device.

Outer Shipping Container

The device(s), and its absorbent/cushioning material, must be packed in

rigid, strong outer packaging.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 Each mailpiece must bear the marking “Manufactured Devices

Containing Less Than 100 mg Mercury.”

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 383

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 8

hazardous material warning label, the identification number, and the

proper shipping name

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

348.4b.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a properly completed shipper's declaration for

dangerous goods must be prepared in triplicate and affixed to the

outside of the mailpiece.

USPS Packaging Instruction 9A

Dry Ice (Carbon Dioxide Solid)

When dry ice is enclosed in a thick metal or other restricting type of

container, a build-up of internal pressure could cause the container to

rupture or explode. Dry ice is permitted to be sent in domestic mail when it is

used as a refrigerant to cool the contents of a mailable hazardous or

nonhazardous material, provided that all applicable requirements in

349 are

met.

Proper Shipping Name

 Carbon Dioxide Solid or Dry Ice.

ID Number

 UN1845.

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted with restriction via air or surface

transportation.

Required Packaging

General

 Packages containing dry ice must be packed in containers that permit

the release of carbon dioxide gas and conform to 49 CFR 173.217 and

175.10(a)(10). If a fiberboard box is used, enough insulation is

necessary to prevent condensation and wetting of the mailing carton.

 For air transportation, each mailpiece may not contain more than

pounds of dry ice.

 For surface transportation, a mailpiece may contain more than

pounds of dry ice.

Appendix C Hazardous, Restricted, and Perishable Mail

384 Publication 52

Marking

 Each mailpiece must be clearly marked on the address side with the

name of the contents being cooled (such as frozen medical specimens,

steaks) and the net weight of the dry ice.

 For air transportation, each mailpiece must bear a Class 9 DOT

miscellaneous hazardous material warning label and must be clearly

marked “Carbon Dioxide Solid, UN1845” Or “Dry Ice, UN1845.”

 For surface transportation, each mailpiece must be clearly marked

“Surface Only” or “Surface Mail Only” and “Carbon Dioxide Solid,

UN1845” or “Dry Ice, UN1845.”

Documentation

 For air transportation, a properly completed shipper's declaration for

dangerous goods must be prepared in triplicate and affixed to the

outside of the mailpiece.

Note: A shipper’s declaration and a Class 9 DOT warning label are not

required for dry ice sent via domestic surface mail. Mailpieces containing

dry ice that are prepared for surface transportation must not, under any

circumstances, be routed via air transportation.

USPS Packaging Instruction 9B

Magnetized Materials

A magnetized material is an article that has a magnetic field strength capable

of causing the deviation of aircraft instruments. Magnetized materials include

magnets and magnetized devices such as magnetrons and light meters of

sufficient strength to possibly cause erroneous aircraft magnetic compass

readings. Magnetized materials are mailable, provided that all requirements

349.24 are met.

Proper Shipping Name and ID Number

 Not applicable.

Mailability

 International Mail: Only non-regulated magnetized materials that have

a magnetic field strength less than 0.002 gauss at a distance of 7 feet

may be sent internationally. Magnetized materials which are regulated

are prohibited. See

622.4.

 Domestic Mail via Air Transportation: Magnetized materials that have a

magnetic field strength greater than 0.00525 gauss at 15 feet are

prohibited. A magnetic field strength less than 0.002 gauss at a

distance of 7 feet is not regulated.

 Domestic Mail via Surface Transportation: Magnetized material is not

regulated as a hazardous material when transported via surface

transportation.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 385

Required Packaging

General

 Magnets and magnetic devices such as magnetrons and light meters

must be packaged with the polarities of each unit positioned to oppose

one another.

 Keeper bars must be installed on permanent magnets or must

otherwise be shielded to prevent the magnetic field from affecting

magnetic compasses.

 Mailable materials must be packed in strong outer containers.

Marking

 For air transportation, the address side of the outer packaging must

bear the magnetized material warning label shown in

Exhibit 349.242b.

 For surface transportation, mailpieces containing magnetized material

with unconfined fields must be clearly marked on the address side with

“Surface Only” or “Surface Mail Only” and “Magnetic - Keep 7 Feet

Away From Navigational Equipment.”

 A complete return address and delivery address must be used.

Documentation

 For air transportation, a properly completed shipper's declaration for

dangerous goods must be prepared in triplicate and affixed to the

outside of the mailpiece. Magnetized material is not regulated as a

hazardous material when transported via surface transportation.

USPS Packaging Instruction 9C

Miscellaneous Hazardous Materials

A Class 9 miscellaneous hazardous material that qualifies as a Limited

Quantity material within the Postal Service is permitted in domestic mail

provided all applicable requirements in

349 are met.

Proper Shipping Name

 Consumer Commodity.

ID Number

 Various (see Appendix A).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via air or surface transportation. Flammable

materials are prohibited from air transportation.

Appendix C Hazardous, Restricted, and Perishable Mail

386 Publication 52

Required Packaging

Primary Receptacle

 For liquids, the capacity of the primary receptacle must not exceed

pint.

 For solids, the weight of the primary receptacle and its contents must

not exceed 1 pound.

 Multiple primary receptacles are permitted.

Cushioning Material

 Enough cushioning material must surround the primary receptacle to

prevent breakage and absorb all potential leakage.

Outer Packaging

 A strong outer packaging that is capable of firmly and securely holding

the primary receptacle and cushioning material is required.

 Each mailpiece must not exceed a total weight of 25 pounds.

Marking

The following labels and text markings must be placed on the address side

of the mailpiece unless specified in

221.1 and 325.1.

 For air transportation, mailpieces must bear the DOT Limited Quantity

air mark (with the symbol “Y” in the center), an approved DOT Class 9

hazardous material warning label, Identification Number “ID8000,” and

the proper shipping name “Consumer Commodity.”

 For surface transportation, the outer packaging must bear an approved

DOT Limited Quantity surface mark designating surface transportation,

prepared under

349.4b.

 A complete return and delivery address must be used.

Documentation

 For air transportation, a mailable material must have a properly

completed shipper's declaration for dangerous goods prepared in

triplicate and affixed to the outside of the mailpiece.

USPS Packaging Instruction 9D

Lithium Metal and Lithium-ion Cells and Batteries

— Domestic

Except according to 349.21, lithium metal (nonrechargeable) cells and

batteries and lithium-ion (rechargeable) cells and batteries are mailable in

limited quantities domestically via air or surface transportation when they are

installed in or packed with the equipment they are intended to operate.

Unless otherwise excepted, lithium metal and lithium-ion batteries (without

equipment) are mailable in limited quantities domestically via surface

transportation only. Lithium metal and lithium-ion batteries installed in or

packed with used, damaged, or defective electronic devices (excluding

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 387

devices that are new in original packaging, and manufacturer-certified new

or refurbished devices) meeting all mailability requirements in

349 are

mailable via surface transportation only.

Proper Shipping Name

 Lithium Metal Battery.

 Lithium-ion Battery.

ID Number

 Lithium-ion Battery, UN3480.

 Lithium Metal Battery, UN3090.

 Lithium-ion Battery contained in equipment, UN3481.

 Lithium-ion Battery packed with equipment, UN3481.

 Lithium Metal Battery contained in equipment, UN3091.

 Lithium Metal Battery packed with equipment, UN 3091.

Mailability

 Lithium metal and lithium-ion cells and batteries installed in or packed

with equipment may be mailable via air or surface transportation.

 Lithium-ion (or lithium polymer) batteries may be mailed, in limited

quantities, via air transportation when both shipped from, and intended

for delivery to, the state of Alaska under

349.222.

 Except as provided above, individual lithium metal (or lithium alloy) and

lithium-ion (or lithium polymer) batteries (without equipment) are

mailable in limited quantities via surface transportation only, provided

the batteries are in the originally sealed packaging, and packaged and

marked as described in

349.221 and 349.222, as applicable.

 Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new or

refurbished devices) containing or packaged with lithium batteries

(see

349.12e) must be mailed via domestic surface transportation only,

provided they meet eligibility requirements in accordance with 349.

Required Packaging

Lithium Metal and Lithium-ion Batteries

 Packaging must meet all applicable requirements specified in 49 CFR

173.185. Except for mailpieces containing button cell batteries

properly installed in the equipment they are intended to operate,

mailpieces containing mailable lithium metal or lithium-ion batteries

must be rigid, sealed, and of adequate size, so the lithium battery mark

can be affixed to the address side without the mark being folded.

 Packaging must be strong enough to prevent crushing of the package

or exposure of the contents during normal handling in the mail.

 The use of padded and poly bags as outer packaging is permitted only

when the mailpieces contain button cell batteries meeting the

classification criteria in

349.11d, the batteries are properly installed in

Appendix C Hazardous, Restricted, and Perishable Mail

388 Publication 52

the equipment they are intended to operate, and the batteries are

afforded adequate protection by that equipment.

 All outer packages must have a complete delivery and return address.

Markings

 Lithium metal batteries properly installed in the equipment they are

intended to operate:

– Except for mailpieces containing button cell batteries installed in

equipment (including circuit boards), or no more than 4 lithium

metal cells or 2 lithium metal batteries installed in the equipment

they operate, mailpieces containing lithium metal batteries must

bear a DOT-approved lithium battery mark, as specified in 49 CFR

173.185(c)(3)(i) and

Exhibit 325.2a, applied to the address side of

the mailpiece.

– The mark must indicate UN3091 for lithium metal cells or batteries

installed in equipment.

– Where a package contains lithium cells or batteries assigned to

different UN numbers, all applicable UN numbers must be

indicated.

– The mark must also include a telephone number for those who

need to obtain additional information.

– Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new

or refurbished devices) must include the text “Restricted Electronic

Device” and “Surface Transportation Only” on the address side of

the mailpiece.

Note: DOT-approved lithium battery markings must be applied to all

mailpieces when there are more than two mailpieces in a single

consignment as defined in

349.12b.

 Lithium metal batteries packed with the equipment they are intended

to operate:

– Mailpieces must bear a DOT-approved lithium battery mark, as

specified in 49 CFR 173.185(c)(3)(i) and

Exhibit 325.2a, applied to

the address side of the mailpiece.

– The mark must indicate UN3091 for lithium metal cells or batteries

packed with equipment.

– The mark must also include a telephone number for those who

need to obtain additional information.

– Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new

or refurbished devices) must include the text “Restricted Electronic

Device” and “Surface Mail Only” on the address side on the

mailpiece.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 389

 Lithium metal batteries not packed with or installed in equipment

(individual batteries):

– Mailpieces must bear a DOT-approved lithium battery mark, as

specified in 49 CFR 173.185(c)(3)(i) and

Exhibit 325.2a, applied to

the address side of the mailpiece.

– The mark must indicate UN3090 for lithium metal cells or batteries.

– The mark must also include a telephone number for those who

need to obtain additional information.

– Mailpieces must also include the text “Surface Mail Only, Primary

Lithium Batteries — Forbidden for Transportation Aboard

Passenger Aircraft” or “Surface Mail Only, Lithium Metal Batteries

— Forbidden for Transportation Aboard Passenger Aircraft.”

 Lithium-ion batteries properly installed in the equipment they are

intended to operate:

– Except for mailpieces containing button cell batteries installed in

equipment (including circuit boards), or no more than 4 lithium-ion

cells or 2 lithium-ion batteries installed in the equipment they

operate, mailpieces containing lithium-ion batteries must bear a

DOT-approved lithium battery mark, as specified in 49 CFR

173.185(c)(3)(i) and

Exhibit 325.2a, applied to the address side of

the mailpiece.

– The mark must indicate UN3481 for lithium-ion cells or batteries

installed in equipment.

– The mark must also include a telephone number for those who

need to obtain additional information.

– Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new

or refurbished devices) must include the text “Restricted Electronic

Device” and “Surface Mail Only” on the address side on the

mailpiece.

Note: DOT-approved lithium battery markings must be applied to all

mailpieces when there are more than two mailpieces in a single

consignment as defined in

349.12b.

 Lithium-ion batteries packed with the equipment they are intended to

operate:

– Mailpieces must bear a DOT-approved lithium battery mark, as

specified in 49 CFR 173.185(c)(3)(i) and

Exhibit 325.2a, applied to

the address side of the mailpiece.

– The mark must indicate UN3481 for lithium-ion cells or batteries

packed with equipment.

– Where a package contains lithium cells or batteries assigned to

different UN numbers, all applicable UN numbers must be

indicated.

– The mark must also include a telephone number for those who

need to obtain additional information.

Appendix C Hazardous, Restricted, and Perishable Mail

390 Publication 52

– Used, damaged, or defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new

or refurbished devices) must include the text “Restricted Electronic

Device” and “Surface Mail Only” on the address side on the

mailpiece.

 Lithium-ion batteries not packed with or installed in equipment

(individual batteries):

– Mailpieces must bear a DOT-approved lithium battery mark, as

specified in 49 CFR 173.185(c)(3)(i) and

Exhibit 325.2a, applied to

the address side of the mailpiece.

– The mark must indicate UN3480 for lithium-ion cells or batteries.

– The mark must also include a telephone number for those who

need to obtain additional information.

– Mailpieces must also include the text “Surface Mail Only,

Secondary Lithium Batteries — Forbidden for Transportation

Aboard Passenger Aircraft” or “Surface Mail Only, Lithium-ion

Batteries — Forbidden for Transportation Aboard Passenger

Aircraft.”

 Used, damaged, or defective electronic devices: In addition to

applicable marking requirements listed above, packages containing

used, damaged, or defective electronic devices (excluding devices that

are new in original packaging, and manufacturer-certified new or

refurbished devices) containing or packaged with lithium batteries

must be marked with the text “Restricted Electronic Device” and

“Surface Transportation Only” on the address side of the package.

(See

221.1 and 325.1.) Products being returned via Parcel Return

Service (PRS), Return Delivery Unit (RDU) or Return Sectional Center

Facility (RSCF) are exempt from this marking requirement.

Quantities

Domestic — Lithium Metal Cells and Batteries:

Installed in or packed with the equipment they are intended to operate:

 Each cell must contain no more than 1.0 gram of lithium content.

 Each battery must contain no more than 2.0 grams aggregate lithium

content.

 The shipment cannot contain more batteries than the number needed

to operate the device.

 Each mailpiece must contain no more than 8 cells or 2 batteries.

Individual batteries mailed without equipment:

 Each cell must contain no more than 1.0 gram of lithium content.

 Each battery must contain no more than 2.0 grams aggregate lithium

content.

 The mailpiece must not exceed 5 pounds.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 391

Domestic — Lithium-ion Cells and Batteries:

Installed in or packed with the equipment they are intended to operate:

 The total watt-hour rating for each cell must not exceed 20 Wh.

 The total watt-hour rating for each battery must not exceed 100 Wh.

 Each mailpiece must contain no more than 8 cells or 2 batteries.

Individual batteries mailed without equipment:

 The total watt-hour rating for each cell must not exceed 20 Wh.

 The total watt-hour rating for each battery must not exceed 100 Wh.

 The mailpiece must not exceed 5 pounds.

Domestic — Small Lithium Metal or Lithium-ion Batteries

Very small, consumer-type batteries, installed in equipment, or packed with

equipment:

 Each lithium metal or lithium alloy cell or battery must contain no more

than 0.3 gram of lithium content.

 Each lithium-ion or lithium polymer cell or battery must not exceed a

watt-hour rating of 2.7 Wh.

 No limit on the number of cells/batteries.

 Each mailpiece must not exceed 2.5 kilograms (5.5 pounds) total

weight.

Appendix C Hazardous, Restricted, and Perishable Mail

392 Publication 52

Domestic Lithium Battery Mailability Exhibit

Surface

Transportation

Air

Transportation

1. Used, damaged, or defective electronic devices are prohibited from air transportation. This excludes devices that are new in

original packaging, and manufacturer-certified new or refurbished devices..

Mailpiece Limitations

2. When a mailpiece limitation of 8 cells or 2 batteries is applicable, a mailpiece may contain either 8 cells or 2 batteries, not both.

Lithium Metal or Lithium Alloy Batteries

3. Each cell must not contain more than 1.0 g of lithium content.

4. Each battery must not contain more than 2.0 g of aggregate lithium content.

Small, non-rechargeable, consumer-type batteries

Contained in (properly i

nstalled in equipment) Mailable Mailable 8 cells or 2 batteries

11 Ibs.

Packed with equipment, but not installed in

e equipment

Mailable Mailable 8 cells or 2 batteries

11 Ibs

Without the equipment they operate

(individual batteries in originally sealed

packaging)

Mailable Prohibited 5 lbs.

Lithium-ion or Lithium Polymer Batteries

5. Each cell must not exceed more than 20 Wh (watt-hour rating).

, 6

6. Each battery must not exceed 100 Wh.

Small, rechargeable, consumer-type batteries

Contained in (properly i

nstalled in equipment) Mailable Mailable 8 cells or 2 batteries

Packed with equipment, but not installed in

e equipment

Mailable Mailable 8 cells or 2 batteries

Without the equipment they operate

ndividual batteries in originally sealed

packaging)

Mailable Prohibited

7. Mailable intra-Alaska via air transportation is limited to 8 cells or 2 batteries.

5 lbs.

Very Small Lithium Metal or Lithium-ion Batteries

8. Each lithium metal or lithium alloy cell or battery must not exceed 0.3 g of lithium content.

, 9

9. Each lithium-ion or lithium polymer cell or battery must not exceed 2.7 Wh.

Exception for very small consumer-type batteries in USPS air transportation

Contained in (properly i

nstalled in equipment) Mailable Mailable No limit on cells/

batteries 5.5 lbs.

Packed with equipment, but not installed in

e equipment

Mailable Mailable No limit on cells/

batteries 5.5 lbs.

Damaged, Defective, or Recalled Batteries

Prohibited, unless approved by

the director,

Product Classification.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 393

USPS Packaging Instruction 9E

Lithium Metal and Lithium-ion Cells and Batteries

— International and APO/FPO/DPO

Lithium metal (non-rechargeable) cells and batteries and lithium-ion

(rechargeable) cells and batteries are mailable in limited quantities

internationally or to and from APO, FPO, or DPO locations only when they are

properly installed in the equipment they operate. Lithium batteries must also

be accepted by the destination country as designated by the Individual

Country Listing in the IMM. APO/FPO/DPO destinations are also subject to

the conditions prescribed by the Department of Defense (DOD) as listed in

Overseas Military/Diplomatic Mail in the Postal Bulletin.

Proper Shipping Name

 Lithium Metal Battery.

 Lithium-ion Battery.

ID Number

 Lithium Metal Battery contained in equipment, UN3091.

 Lithium-ion Battery contained in equipment, UN3481.

Mailability

 Lithium metal and lithium-ion cells and batteries installed in the

equipment they are intended to operate (UN3091 and UN3481) are

mailable.

 Lithium metal and lithium-ion cells and batteries not packed in

equipment (i.e., batteries packed with equipment or batteries sent

separately from equipment) are prohibited.

 Used, damaged, and defective electronic devices (excluding devices

that are new in original packaging, and manufacturer-certified new or

refurbished devices) containing lithium batteries are prohibited

(see

623).

Required Packaging

Lithium Metal and Lithium-ion Batteries

 The equipment must be cushioned to prevent movement or damage,

and must be contained in rigid outer packaging, sealed and strong

enough to prevent crushing of the package or exposure of the contents

during normal handling in the mail.

 All outer packages must have a complete delivery and return address.

Markings

 Lithium metal batteries properly installed in the equipment they are

intended to operate:

– Mailable internationally when permitted by country, including to

and from APO, FPO, and DPO locations.

Appendix C Hazardous, Restricted, and Perishable Mail

394 Publication 52

– No lithium battery markings permitted. Quantities must be within

the limits of

622.5 and as outlined below.

 Lithium-ion batteries properly installed in the equipment they are

intended to operate:

– Mailable internationally when permitted by country, including to

and from APO, FPO, and DPO locations.

– No lithium battery markings permitted. Quantities must be within

the limits of

622.5 and as outlined below.

Quantities

International — Lithium Metal and Lithium-ion Cells and Batteries:

Installed in equipment:

 Each shipment may contain a maximum of four lithium-ion cells or two

lithium-ion batteries.

 The total watt-hour rating for each cell must not exceed 20 Wh.

 The total watt-hour rating for each battery must not exceed 100 Wh.

Note: A lithium battery consignment, as defined in 349.12b, is limited to

a maximum of two mailpieces for all international and APO/FPO/DPO

mailings.

International — Very Small Lithium Metal and Lithium-ion Cells and

Batteries:

Installed in equipment:

 Each shipment containing very small lithium cells and batteries, when

installed in the equipment they operate (including circuit boards), may

contain a maximum of four lithium cells or two lithium batteries.

 Lithium metal cells and batteries must contain no more than 0.3 gram

of lithium content.

 Lithium-ion cells/batteries must have watt-hour rating of not more than

2.7 Wh.

Note: A lithium battery consignment, as defined in 349.12b, is limited to

a maximum of two mailpieces for all international and APO/FPO/DPO

mailings.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 395

International Lithium Battery Mailability

Exhibit

International

APO/FPO/DPO

1, 2

Mailpiece

Battery Limit

Lithium Metal or Lithium Alloy Batteries

4, 5

Small, non-rechargeable, consumer-type batteries

Contained in (properly installed in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the equipment Prohibited

Without the equipment they operate (i

ndividual batteries in

originally sealed packaging)

Prohibited

Lithium-ion or Lithium Polymer Batteries

6, 7

Small, rechargeable, consumer-type batteries

Contained in (properly i

nstalled in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the equipment Prohibited

Without the equipment they operate (i

ndividual batteries in

originally sealed packaging)

Prohibited

Very Small Lithium Metal or Lithium-ion Batteries

8, 9

Exception for very small consumer-type batteries in international mailings

Contained in (properly installed in equipment) Mailable Maximum of 4 cells or

2 batteries

Packed with equipment, but not installed in the equipment Prohibited

Without the equipment they operate (i

ndividual batteries in

originally sealed packaging)

Prohibited

1. Unless otherwise prohibited by the international destination country or specific APO/FPO/DPO ZIP Code location.

2. Used, damaged, defective, or recalled lithium batteries and use

d damaged, or defective electronic devices containing lithium

batteries are prohibited and may not be mailed internationally or to, from or between APO, FPO, or DPO locations under any

circumstances. This excludes electronic devices that are new in original packaging, and manufacturer-certified new or

refurbished devices.

3. When a mailpiece limitation of 4 cells or 2 batteries is applicable, a mailpiece may co

ntain either 4 cells or 2 batteries, not both.

4. Each lithium metal or lithium alloy cell must not conta

in more than 1.0 g (gram) of lithium content.

5. Each lithium metal or lithium alloy

battery must not contain more than 2.0 g of aggregate lithium content.

6. Each lithium-ion or lithium polymer cell must not exceed more than 20 W

h (watt-hour rating).

7. Each lithium-ion or lithium polymer b

attery must not exceed 100 Wh.

8. Each lithium metal or lithium alloy cell or batter

y must not exceed 0.3 g of lithium content.

9. Each lithium-ion or lithium polymer cell or battery must not exceed a w

att-hour rating of 2.7 Wh.

Note: Shipments containing lithium batteries are not permitted in Global Express Guaranteed

mailpieces.

USPS Packaging Instruction 10A

Small-Quantity Provision

Some types of hazardous materials, as permitted in 338 and 49 CFR 173.4,

may be prepared for mailing using the “small-quantity” provis

ion. The small-

quantity provision is unique within the United States, and its use is prohibited

in international and APO/FPO/DPO mail.

Appendix C Hazardous, Restricted, and Perishable Mail

396 Publication 52

Proper Shipping Name and ID Number

 Not applicable.

Prototype Testing Requirement

 The complete mailing package must be capable of withstanding the

test criteria in 49 CFR 173.4(a)(6).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via surface transportation only.

Required Packaging

Inner Receptacle

 Each inner receptacle is limited to 30 milliliters or 1 ounce or less for

liquids.

 Each inner receptacle is limited to 30 grams or 1 ounce or less for

solids.

 Each inner receptacle cannot be liquid-full at 131° F (55° C).

 Each inner receptacle must be constructed of plastic with a minimum

thickness of no less than 0.2 mm (0.008 inch) or must be made of

earthenware, glass, or metal.

 Each inner receptacle must be securely sealed with wire, tape, or other

positive means.

Absorbent and Cushioning Material

 Sufficient absorbent material that will not react chemically with the

hazardous material must fully surround each inner receptacle and be

capable of absorbing the entire liquid contents of the inner

receptacle(s) in case of leakage.

 Each primary receptacle must be surrounded by sufficient cushioning

material to absorb shock and prevent breakage.

 The absorbent and cushioning materials used must not violate 49 CFR

173.21.

Secondary Packaging

 Each inner receptacle and the absorbent cushioning material must be

placed within a securely sealed secondary packaging.

Outer Packaging

 The secondary packaging must be securely packed in a strong outer

packaging.

 The total weight of each mailpiece must not exceed 64 pounds (29 kg).

Marking

 The address side of each mailpiece sent under the small quantity

provision must be clearly marked with “This package conforms to 49

CFR 173.4 for domestic highway or rail transport only.”

 A complete return address and delivery address must be used.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 397

USPS Packaging Instruction 10B

Excepted Quantity Provision

Some types of hazardous materials, as permitted in 337 and 49 CFR 173.4a,

may be prepared for mailing using the excepted quantity provision. The

excepted quantity provision, although applicable to international shipments

by commercial shippers, is limited to domestic mail, and its use is prohibited

in international and APO/FPO/DPO mail.

Proper Shipping Name and ID Number

 Not applicable.

Prototype Testing Requirement

 The complete mailing package must be capable of withstanding the

test criteria in 49 CFR 173.4a(f).

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via air or surface transportation (highway,

rail, or vessel).

Required Packaging

Inner (Primary) Receptacle

 Each inner receptacle must be constructed of plastic, glass, porcelain,

stoneware, earthenware, or metal. Plastic inner packaging must have a

thickness of not less than 0.2 mm (0.008 inch).

 Each inner packaging with a removable closure must have its closure

held securely in place with wire, tape, or other positive means.

 Each inner receptacle having a neck with molded screw threads must

have a leak-proof, threaded-type cap.

 Closures must not react chemically with the material.

Intermediate (Secondary) Packaging

 Each inner receptacle must be securely packed in an intermediate

container with cushioning material in such a way that, under normal

conditions of transport, will not break, be punctured, or leak.

 Intermediate containers must completely contain the contents in case

of breakage or leakage, regardless of package orientation.

Absorbent and Cushioning Material

For liquids, intermediate containers must contain sufficient absorbent material that:

 Will absorb the entire contents of the inner packaging.

 Will not react dangerously with the material or reduce the integrity or

function of the packaging materials.

 The absorbent material may be the cushioning material.

Appendix C Hazardous, Restricted, and Perishable Mail

398 Publication 52

Outer Packaging

 The intermediate packaging must be securely packed in strong, rigid

outer packaging.

 Placement of the material in the package must not violate 49 CFR

173.21.

 Outer packages must be of such a size that there is adequate space to

apply all necessary markings.

Markings

 Mailpieces must be durably and legibly marked with the following

marking:

 The “*” must be replaced by the primary hazard class, or when

assigned, the division of each of the hazardous materials contained in

the package. The “**” must be replaced by the name of the mail owner

or mail service provider, if not shown elsewhere on the package.

 The marking must be located on the address side of the mailpiece, not

be less than 100 mm (3.9 inches) by 100 mm (3.9 inches), and must be

durable and clearly visible.

Documentation

 For ground transportation (highway or rail), no shipping paper is

required.

 For surface transportation by vessel, a shipping paper is required and

must include the statement “Dangerous Goods in Excepted Quantities”

and indicate the number of packages.

 For transport by air, a shipping paper is not required.

USPS Packaging Instructions 10C

Cremated Remains

Human and animal ashes are permitted for mailing with restrictions, provided

they are properly double-packaged and labeled. For international shipping,

cremated remains are permitted to be mailed provided they are not

otherwise prohibited by the destination country (see the Individual Country

Listings in the IMM) and all packaging and marking requirements are met.

Proper Shipping Name

Not applicable.

ID Number

Not applicable.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 399

Mailability

 International Mail: When permitted by the destination country only via

Priority Mail Express International service (this class of mail must also

be available to the destination country).

 Domestic Mail: Permitted via Priority Mail Express service only.

Required Packaging

Primary Container

 International: A funeral urn is required as the inner container. It must be

sealed and siftproof.

 Domestic: The inner container must be strong and durable and be

constructed in such a manner as to protect and securely contain the

contents inside and it must be properly sealed so that it is siftproof.

Note: A siftproof container is any vessel that does not allow loose

powder to leak or sift out during transit.

Cushioning Material

 For both domestic and international shipping, the space between the

primary receptacle and the outer packaging must contain enough

material to keep the item stable during transit and to absorb the shock

to prevent breakage.

Outer Container

 For both domestic and international shipping, the outer container must

be strong, durable, and siftproof. Insert your inner container into the

shipping box and add padding to the bottom, sides, and top to prevent

movement. Make sure there is no movement of contents within the

shipping box.

Note: It is recommended that all packages contain a slip of paper with

the sender’s and recipient’s address and phone number. This will

provide Postal employees with a means to contact you if the outer

mailing label is damaged or found missing during transit.

Marking

 Domestic: A complete return address and delivery address must be

used. The Priority Mail Express mailpiece (USPS-produced or

customer supplied) must be marked with Label 139, Cremated

Remains, affixed to all sides (including top and bottom), or a mailer may

use the special Priority Mail Express cremated remains branded box

(BOX-CRE) available on

usps.com.

 International: A complete return address and delivery address must be

used. The mailer must indicate the contents (Cremated Remains) on

the required applicable customs declaration form. The Priority Mail

Express International mailpiece (USPS-produced or customer

supplied) must be marked with Label 139, Cremated Remains, affixed

to all sides (including top and bottom), or a mailer may use the special

Priority Mail Express cremated remains branded box (BOX-CRE)

available on

usps.com.

Appendix C Hazardous, Restricted, and Perishable Mail

400 Publication 52

Documentation

 International: A complete and accurate customs label is required and

must indicate the contents of the package. If available, the cremation

certificate should be attached to the outer packaging, or made easily

accessible. The sender is responsible for obtaining all the necessary

permissions required by the national laws in the country of origin and

the country of destination prior to dispatching these items.

USPS Packaging Instruction 10D

Adult Bird Boxes

Disease-free adult birds may be mailed domestically when shipped under all

applicable governmental laws and regulations, including the Lacey Act, the

Endangered Species Act (ESA), the Animal Welfare Act, regulations of the

U.S. Department of Agriculture, U.S. Fish and Wildlife Service, and any state,

municipal, or local ordinances. Each container must meet container

specifications. See

521, 522, and 526.4.

Proper Shipping Name

Not applicable.

ID Number

Not applicable.

Mailability

 International Mail: Prohibited.

 Domestic Mail: Permitted via Priority Mail Express service only.

Required Packaging

Containers must be designed with consideration of the birds’ comfort,

awareness, health, and welfare, including possible temperature fluctuations

that may occur during transport. In addition, the container must:

 Remain intact and withstand crushing during transportation.

 Prevent the birds from puncturing or breaking any part of the container

with their own force, or escaping from the container.

 Contain shavings or similar absorbent material to prevent damage to

the bottom of the container.

 Have a secure window (covered and sturdy) designated for a visible

inspection of the birds.

 Provide sufficient exposure to air to allow the birds to breathe normally

through filter-covered ventilation that minimizes the chance of handler

contact with solid or aerosolized waste.

USPS Packaging Instructions for Mailable Hazardous Materials Appendix C

September 7, 2023 401

Marking

Each container must be marked with the following information:

 “Live Birds — USPS Approved Container # (once issued).”

 Complete sender’s and recipient’s addresses (including phone

numbers) on the outer packaging for the necessary notification by

Postal Service personnel.

 Directional arrows indicating “up” position (on at least two sides of the

container).

Hazardous, Restricted, and Perishable Mail

402 Publication 52

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September 7, 2023 403

Appendix D

Hazardous Materials Definitions

Aerosol means any nonrefillable metal receptacle containing a gas that is

compressed, liquified, or dissolved under pressure, the sole purpose of

which is to expel a nonpoisonous (other than a Division 6.1 Packing Group III

material) liquid, paste, or powder and fitted with a self-closing release device

allowing the contents to be ejected by the gas.

Air transportation requirements apply to all mailable hazardous materials

sent at Priority Mail Express or Priority Mail prices for domestic shipments, or

Priority Mail Express International, Priority Mail International, and First-Class

Package International Service prices for international shipments. All mailable

hazardous materials sent at those prices must meet the requirements that

apply to air transportation. Mailable hazardous materials sent at any of those

prices may or may not be transported via air depending on the distance

between the point of origination and the point of destination, and the ability

of USPS to obtain an air carrier between those points.

Ammunition includes all kinds of bombs, grenades, rockets, mines,

projectiles, and other similar devices or contrivances. Ammunition is a

Class

1 explosive and is nonmailable.

ASTM refers to the American Society for Testing and Materials.

Batteries, dry are sealed, nonvented batteries of the type used in flashlights

or for the operation of small household apparatus. They contain zinc salts

and other solids, or may be of the nickel cadmium type or other

combinations of metals.

Biohazard is a biological material that poses a threat to humans or the

environment. The biohazard symbol that is required for certain Division 6.2

materials is an OSHA requirement detailed in 29 CFR 1910.1030.

Biological products means a material derived from a living organism that is

prepared and manufactured in accordance with 9 CFR 102-104 (licenses for

biological products; experimental products, distribution, and evaluation prior

to licensing; and permits for biological products), 21 CFR 312 (investigational

new drug application), or 21 CFR 600-680 (biologics) and that, under such

provisions, may be shipped in interstate commerce. Biological products

include, but are not limited to, products such as vaccines.

Btu means British thermal unit.

C means degrees Celsius or Centigrade. Celsius or Centigrade is a

thermometer scale on which the freezing and boiling points of water are

divided into 100, with 0° representing the freezing point and 100° the boiling

point.

Appendix D Hazardous, Restricted, and Perishable Mail

404 Publication 52

Cargo aircraft only means an aircraft that is used to transport cargo and is

not engaged in carrying passengers.

Ci means curie.

Clinical (diagnostic) specimen is any human or animal material including,

but not limited to, excreta, secreta, blood, blood components, tissue, and

tissue fluids that have been collected and are being mailed to a medical or

forensic laboratory for the purpose of diagnosis, or being mailed from a

medical or forensic laboratory for return to a law enforcement agency.

Combination packaging means one or more inner packagings (i.e.,

receptacles) secured in a nonbulk outer packaging. This is a term used by

DOT in 49 CFR.

Combustible liquid is a Class 3 material in a liquid form that has a flashpoint

above 140° F (60° C) and below 200° F (93° C).

Compatibility group refers to a designated alphabetical letter used to

categorize different types of Class 1 explosive substances and articles for

purposes of safe stowage and segregation (e.g., Division 1.4S).

Composite packaging consists of an outer packaging and an inner

receptacle so constructed that they form an integral unit. Once assembled, it

remains a single integrated unit; it is filled, stored, shipped, and emptied as

such. This is a term used by DOT in 49 CFR.

Compressed gas is a material or mixture within a container that is a gas at

68° F (20° C) or less and 14.7 psi (101.3 kPa), or exerts an absolute pressure

of 40.6 psia (280 kPa) or greater at 68° F (20° C). Gases are Class

hazardous materials.

Consumer commodity is a hazardous material that is packaged and

distributed in a quantity and form intended or suitable for retail sale and

designed for individual consumption for personal care or household use

purposes. This term can also include certain drugs or medicines.

Corrosive material means a Class 8 liquid or solid material that causes

visible destruction of human skin at the site of contact within a specified

period of time. A liquid that has a severe corrosion rate on steel or aluminum

is also a corrosive material.

Dangerous goods is the term used to describe hazardous materials shipped

in international commerce.

Dangerous when wet material is a Division 4.3 material that by contact with

water is liable to become spontaneously flammable or to give off flammable

or toxic gas.

De minimis is the maximum quantity of Packing Group II & III in Class 3,

Division 4.1, Division 4.2, Division 4.3, Division 5.1, Division 6.1, Class 8, and

Class 9 materials that do not meet the definition of hazardous material. Inner

receptacles or articles are limited to One (1) ml (0.03 ounce) for liquids; and

One (1) gram (0.04 ounce) for solid materials and 100 ml (3.38 ounces) for

liquids; and 100 g (0.22 pounds) for solid materials total aggregate per

mailpiece. De minimis does not apply to prohibited items (e.g., mercury,

hydrofluoric acid).

Hazardous Materials Definitions Appendix D

September 7, 2023 405

Designated facility is (for EPA purposes) the hazardous waste treatment,

storage, or disposal facility that has been designated on a hazardous waste

manifest by the waste generator.

Diagnostic specimen, see clinical specimen.

Division refers to a subpart of a hazard class (e.g., Division 6.1).

DOD refers to the U.S. Department of Defense.

Domestic transportation is transportation between locations within the

United States.

DOT refers to the U.S. Department of Transportation. DOT has the federal

authority to regulate the transportation of hazardous materials within

domestic commerce. DOT regulations are codified in Title 49, Code of

Federal Regulations (49 CFR).

Elevated temperature material means a material that, when offered for

transportation, is in a liquid phase and at a temperature at or above 212° F

(100° C); is in a liquid phase with a flashpoint at or above 100° F (37.8° C) that

is intentionally heated and offered for transportation at or above its

flashpoint; or is in a solid phase and at a temperature at or above 464° F

(240° C). Elevated temperature materials are Class 9 hazardous materials

and are nonmailable.

EPA refers to the U.S. Environmental Protection Agency. EPA regulations are

codified in Title 40, Code of Federal Regulations (40 CFR).

Etiologic agent, see infectious substance.

Explosive is any Class 1 substance or article, including a device, that is

designed to function by explosion (i.e., an extremely rapid release of gas and

heat) or that, by chemical reaction within itself, is able to function in a similar

manner.

F means degrees Fahrenheit. Fahrenheit is a thermometer scale on which the

boiling point of water is 212° above zero and the freezing point is 32° above

zero.

Flammable gas is a Division 2.1 material that is ignitable at 14.7 psi

(101.3

kPa) when in a mixture of 13 percent or less by volume, or has a

flammable range at 14.7 psi (101.3 kPa) with air of at least 12 percent

regardless of the lower limit.

Flammable liquid is a Class 3 material in a liquid form that has a flashpoint

of not more than 140° F (60° C), or any material in a liquid phase with a

flashpoint at or above 100° F (38° C).

Flammable solid is a Division 4.1 material that includes any solid material

(other than one classed as an explosive) that under normal transport and

handling conditions is likely to cause fire through friction or retained heat

from manufacturing or processing, or that can be ignited readily and, when

ignited, can burn vigorously and persistently and create a serious

transportation hazard.

Flashpoint means the minimum temperature at which a liquid gives off vapor

within a test vessel in sufficient concentration to form an ignitable mixture

with air near the surface of the liquid. The test criteria is cited in 49 CFR

173.120(c).

Appendix D Hazardous, Restricted, and Perishable Mail

406 Publication 52

Gas means a material that has a vapor pressure greater than 43.5 psi

(300

kPa) at 122° F (50° C) or is completely gaseous at 68° F (20° C) at a

standard pressure of 14.7psi (101.3 kPa). Also, see compressed gas.

Hazard class means the category to which a hazardous material is assigned

under the definitions set by DOT in 49 CFR. Even though a material is

assigned to only one hazard class, it may meet the defining criteria for more

than one hazard class. Some hazardous materials may also have subsidiary

hazard class assignment.

Hazard zone refers to one of the four levels of hazards (Hazard Zones A

through D) assigned to gases and liquids that are poisonous by inhalation. A

hazard zone is based on the LC

value for acute inhalation and toxicity of

gases and vapors. Hazardous materials assigned a hazard zone are

nonmailable.

Hazardous material is any article or substance designated by the U.S.

Department of Transportation (DOT) as being capable of posing an

unreasonable risk to health, safety, or property during transportation. In

international commerce, hazardous materials are known as “dangerous goods.”

Hazardous substance is a hazardous material that when shipped in certain

quantities can be an environmental hazard. Appendix A in 49 CFR 172.101

lists all hazardous substances. All hazardous substances are hazardous

materials, but not all hazardous materials are hazardous substances.

Hazardous substances are nonmailable.

Hazardous waste is any material subject to the Hazardous Waste Manifest

Requirements of EPA as specified in 40 CFR 262. The only type of hazardous

waste permitted in domestic mail is medical waste (i.e., sharps and other

medical devices) as specified in

346.

IATA refers to the International Air Transportation Association. IATA annually

publishes the IATA Dangerous Goods Regulations, which provides

procedures for shippers to prepare hazardous materials for safe transport by

air via commercial air transportation. The IATA regulations contain all of the

ICAO Technical Instructions as well as some more restrictive requirements

that reflect air transport industry standard practices or operational

considerations.

ICAO refers to the International Civil Aviation Organization. ICAO biannually

publishes the Technical Instructions for the Safe Transport of Dangerous

Goods by Air, which specifies the procedures for shipping hazardous

materials via air transportation and is recognized by DOT in 49 CFR 171.11.

ID8000 is a miscellaneous hazardous class specific to certain materials

within Classes 2, 3, 6.1, and 9 that can qualify as a mailable consumer

commodity material and are reclassed as ID8000 when intended for air

transportation.

IMO refers to the International Maritime Organization, which provides

requirements for shipping hazardous materials via waterways.

Infectious substance (etiologic agent) is a Division 6.2 material that is a

viable microorganism, or its toxin, and causes or may cause disease in

human beings or animals, and includes those agents listed in 42 CFR 72.3

Hazardous Materials Definitions Appendix D

September 7, 2023 407

and any other agent that causes or may cause severe, disabling, or fatal

disease. The terms “infectious substance” and “etiologic agent” are

synonymous.

Inhalation hazard, see hazard zone.

Inner receptacle, see primary receptacle.

Irritating material is any Division 6.1 liquid or solid substance (e.g., tear gas)

that gives off intense fumes and causes extreme but temporary irritation and

impairment to a person’s ability to function.

kPa means kilopascals.

L or l means liter.

Limited Quantity is the maximum amount of a specific hazardous material

that is exempted from the labeling or packaging requirements in 49 CFR. To

be permitted in the Postal Service, hazardous materials that are classified to

be shipped as Limited Quantity must also qualify as a consumer commodity

material. See Consumer Commodity, Limited Quantity air and Limited

Quantity surface.

Limited Quantity Air is a category unique to the Postal Service of a

hazardous material in hazard Classes 5, 8, and portions of 9 that presents a

limited hazard specifically in air transportation and is mailable under certain

conditions in Postal Service air networks.

Limited Quantity Surface is a material that contains a limited quantity of a

hazardous material that presents a limited hazard during transportation due

to its form, quantity, and packaging, specific to the Postal Service, and is

restricted to surface transportation. This category generally must also qualify

as a consumer commodity to be accepted in the Postal Service network.

This material was previously classified as ORM-D.

Liquid is a material, other than an elevated temperature material, with a

melting point of 68° F (20° C) or lower at a standard pressure of 14.7 psi

(101.3 kPa).

Liquid phase means a material that meets the definition of a liquid when

elevated at the higher of the temperature at which it is offered for

transportation, not at the 100° F (38° C) temperature.

Mailable Limited Quantity is a hazardous material in hazard Classes 4, 5, 8

or portions of 9 that presents a limited hazard during transportation

(specifically air transport), and is mailable in USPS air networks under certain

conditions and in limited quantities.

Magnetized material is an article that has a magnetic field strength capable

of causing the deviation of aircraft instruments and producing erroneous

aircraft magnetic compass readings.

Marine pollutant is any hazardous material listed in Appendix B of 49 CFR

172.101, including mixtures or solutions of certain concentrations that are

capable of polluting water habitats. Marine pollutants are not mailable.

Material Safety Data Sheet (MSDS), see Safety Data Sheet (SDS).

Maximum capacity means the maximum volume permitted in the inner

receptacle or packaging.

Appendix D Hazardous, Restricted, and Perishable Mail

408 Publication 52

Miscellaneous hazardous materials are Class 9 substances or articles that

present a hazard during transportation but do not meet the definition of any

other hazard class. Examples are dry ice and magnetized materials.

ml means milliliter.

mm means millimeters.

NA number refers to the North American (NA) four-digit identification

number assigned to a hazardous material that is not recognized for

international transportation. Hazardous materials having NA numbers may be

shipped in commercial commerce only within the United States or between

the United States and Canada. Hazardous materials with NA numbers may

be mailed within the United States only as permitted in Chapter

Nonflammable gas is a Division 2.2 material that exerts an absolute

pressure of 40.6 psia (280 kPa) or greater at 68° F (20° C).

n.o.s. means not

otherwise specified.

Organic peroxide is a Division 5.2 material that includes any organic

compound containing oxygen in the bivalent structure and that may be

considered a derivative of hydrogen peroxide, where one or more of the

hydrogen atoms have been replaced by organic radicals.

ORM means other regulated material.

ORM-D (other regulated materials for domestic transport only) was a

marking for mail or shipping in the United States. Packages bearing this mark

contained hazardous material in a limited quantity that present a limited

hazard during transportation, due to its form, quantity, and packaging. ORM-D

was phased out by the U.S. Department of Transportation on Jan. 1, 2021.

OSHA refers to the Occupational Safety and Health Administration of the

U.S. Department of Labor. OSHA regulations are codified in Title 29, Code of

Federal Regulations (29 CFR).

Other medical devices are Division 6.2 materials that include all articles or

devices used in animal or human patient care or treatment or in medical

research that are not, or do not contain, a projecting sharp and are not

known or not reasonably believed to contain an infectious substance

(etiologic agent).

Outer packaging is the outermost enclosure that provides protection

against the unintentional release of the contents under normal handling

conditions. The outer packaging holds the primary receptacle, the secondary

packaging (if required), and the absorbent material and cushioning. The outer

packaging bears the addressing information along with all required markings

and labels.

Oxidizing gas means a gas that more than air may cause or contribute to the

combustion of other material by generally providing oxygen.

Oxidizing substance is a Division 5.2 material that may, generally by

yielding oxygen, cause or enhance the combustion of other materials.

Packing group (PG) is the DOT grouping assignment that is based on the

degree of danger present in an individual hazardous material. Packing Group

I indicates a great danger; Packing Group II, medium danger; Packing Group

III, minor danger. Not every hazard class uses packing group assignments.

ORM-D materials most often fall within Packing Group III.

Hazardous Materials Definitions Appendix D

September 7, 2023 409

Passenger-carrying aircraft means an aircraft that carries any person other

than a crew member or company employee, an authorized representative of

the United States, or a person accompanying the shipment.

Poisonous gas, see toxic gas.

Poisonous material, see toxic substance.

Primary hazard refers to the single or most dangerous hazard characteristic

of a hazardous material (i.e., hazard class or division assignment).

Primary receptacle is the innermost container (i.e., tube, vial, bottle, vessel)

that holds the hazardous material. Sometimes the primary receptacle may be

referred to as the inner receptacle or the primary container.

Proper shipping name is the name of a hazardous material that must be

used to identify a substance or article in the shipping documents and on the

packaging, as required. See Appendix

A and B for listings of proper shipping

names.

psi means pounds per square inch.

psia means pounds per square inch absolute.

psig means pounds per square inch gauge.

Pyrophoric material is a liquid or solid that, even in a small amount and

without an external ignition source, can ignite within 5 minutes after coming

in contact with air.

Radiation level means the radiation dose-equivalent rate expressed in

millisievert per hour (mSv/h) or millirem per hour (mrem/h).

Radioactive instrument or article means any manufactured instrument or

article, such as an instrument, clock, electronic tube or apparatus, or similar

item, having a Class 7 radioactive material in gaseous or nondispersible solid

form as a component part.

Radioactive material is defined in 49 CFR 173.403 as any material

containing radionuclides where both the activity concentration and the total

activity in the consignment exceed the values specified in the table in 49

CFR

173.436 or values derived according to the instructions in 49 CFR 173.433.

Activity limits for mailable Class 7 radioactive materials are listed in

Exhibit 347.22.

Regulated medical waste is the DOT term for a Division 6.2 waste or

reusable material, other than a culture or stock of an infectious substance,

that may or may not contain an infectious substance and is generated from:

the diagnosis, treatment, or immunization of human beings or animals;

research pertaining to the diagnosis, treatment, or immunization of human

beings or animals; or the production or testing of biological products. Only

the types of medical waste named in

346 are mailable.

Reportable quantity (RQ) mean the minimum amount of a hazardous

substance that is subject to the additional marking and documentation

requirements in Appendix A of 49 CFR 172.101. A hazardous material having

an RQ is nonmailable.

Residue means the hazardous material remaining in a packaging after the

contents have been unloaded to the maximum extent practicable and before

the packaging is either cleaned, refilled, or properly disposed of.

Appendix D Hazardous, Restricted, and Perishable Mail

410 Publication 52

Rigid means unable to bend or be forced out of shape; not flexible. A rigid

outer shipping container or rigid packaging is generally interpreted to mean a

fiberboard (cardboard) box or outer packaging of equivalent strength,

durability and rigidity.

Safety Data Sheet (SDS) is a document that details the physical

characteristics and health hazards of a chemical or hazardous product. In

CFR 1910.1200(g), OSHA requires chemical manufacturers, distributors,

and importers to provide SDSs to communicate the hazards of hazardous

chemicals they produce or import, and provide copies to their customers.

OSHA also requires that employers have an SDS on hand for each

hazardous chemical present in their workplace. For postal purposes, the

information on an SDS can be useful in determining the mailability of a

hazardous material.

Salvage packaging is a special form of packaging into which damaged,

defective, or leaking hazardous materials packages are placed for purposes

of recovery or disposal. Salvage packaging must meet the specifications in

49 CFR 173.3.

Secondary packaging container is the packaging component into which

the primary receptacle(s) and any required absorbent and cushioning

material is securely placed. The packaging of certain mailable hazardous

materials requires the use of a secondary container. The secondary

packaging container is then secured in an outer shipping container.

Self-heating material is a material that, when in contact with air and without

an energy supply, is liable to self-heat and may spontaneously ignite.

Sharps is a Division 6.2 material that includes any item of medical waste

having a projecting cutting edge or fine point that was used in animal or

human patient care or treatment or in medical research or industrial

laboratories. The term includes, but is not limited to, hypodermic needles,

syringes (with or without the attached needles), pasteur pipettes, scalpel

blades, blood vials, needles with attached tubing, and culture dishes

(regardless of the presence of infectious agents). Also included are other

types of broken or unbroken glassware that were in contact with infectious

agents, such as used slides or cover slips. The term does not include new

unused medical devices such as hypodermic needles, syringes, and scalpel

blades.

Shipping papers means the shipping order, bill of lading, manifest, or other

shipping document that contains the information required by 49 CFR

172.200 through 172.204. Most hazardous materials (including ORM-D

materials) sent via air transportation require a shipper’s declaration for

dangerous goods. See

326 and Exhibit 326. The Packaging Instructions in

Appendix C specify when a shipper’s declaration is required.

Siftproof packaging means a packaging that is impermeable to dry

contents, including any fine solid material produced during transportation.

Small quantity is the maximum amount of a specific hazardous material that

is not subject to any requirements other than those in 49 CFR 173.4. Not

every hazardous material is eligible to be shipped as a small quantity. The

Hazardous Materials Definitions Appendix D

September 7, 2023 411

small quantity provision is recognized for use within the United States only. A

hazardous material cannot be sent in international mail using the small

quantity provision.

Solid is a material that is not a liquid or a gas.

Solution is any homogeneous liquid mixture of two or more chemical

compounds or elements that will not undergo any segregation under normal

transportation conditions.

Specific activity refers to the activity of the radionuclide per unit mass of

that nuclide for a Class 7 material.

Specification packaging means a packaging conforming to one of the

specifications or standards in 49 CFR 178 and 179. ORM-D materials do not

require specification packaging (but they must meet postal packaging

requirements).

Spontaneously combustible material is a pyrophoric or a self-heating

material that is capable of spontaneous ignition.

Subsidiary hazard means a hazard characteristic, other than the primary

hazard, present in a hazardous material that is of lesser significance than the

primary hazard.

Surface transportation requirements apply to all mailable hazardous

materials sent at the Parcel Select Lightweight or USPS Ground Advantage

prices and must meet the requirements that apply to surface transportation.

TBq means terabecquerel.

Toxic gas is a Division 2.3 material that is poisonous by inhalation and is a

gas at 68° F (20° C) or less and a pressure of 14.7 psi (101.3 kPa); or a

material that has a boiling point of 68° F (20° C) or less at 14.7 psi

(101.3

kPa).

Toxic substance means a material, other than a gas, that is known to be so

toxic to humans as to cause death, injury, or harm to health if swallowed,

inhaled, or contacted by the skin. See

346 for information on toxicity levels.

UN number refers to the United Nations (UN) four-digit identification number

assigned to a hazardous material that is recognized for use in international

and domestic commerce and transportation.

UN standard packaging means a packaging that conforms to the standards

in the UN Recommendations on the Transport of Dangerous Goods.

Viscosity is the tendency of a fluid to resist internal flow without regard to its

density.

Volatility refers to the relative rate of evaporation of materials to assume a

vapor state at ordinary temperatures.

Water reactive material, see dangerous when wet material.

Water resistant means having a degree of resistance to permeability and

damage caused by water.

Hazardous, Restricted, and Perishable Mail

412 Publication 52

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September 7, 2023 413

Appendix E

References

Postal Service Publications and Reference

Materials

 Mailing Standards of the United States Postal Service, Domestic Mail

Manual (DMM®).

 Mailing Standards of the United States Postal Service, International

Mail Manual (IMM®).

 Postal Operations Manual (POM).

 Administrative Support Manual (ASM).

 Publication 14, Prohibitions and Restrictions on Mailing Animals,

Plants, and Related Matter.

 Handbook EL-812, Hazardous Materials and Spill Response.

 Aviation Mail Security, Management Instructions.

 Notice 107, Let’s Keep the Mail Safe.

 Poster 298, DOT Hazardous Materials Warning Labels and Markings.

 Poster 702, Dangerous Goods Warning Labels Prohibited in

International Mail.

Other Publications

 Title 18 of the United States Code (U.S.C.) 921, 1715, 1716

(18 U.S.C. 921, 1715, 1716).

 39 U.S.C. 3001 (nonmailable matter).

 21 U.S.C. 801–830 (drugs).

 Title 29 Code of Federal Regulations (29 CFR), Occupational Safety

and Health Administration (OSHA), U.S. Department of Labor.

 42 CFR, Department of Health and Human Services (HHS), Centers for

Disease Control and Prevention (CDC).

 49 CFR, Parts 100–185, U.S. Department of Transportation (DOT).

 International Civil Aviation Organization (ICAO), Technical Instructions

for the Safe Transport of Dangerous Goods by Air.

 International Air Transport Association (IATA), Dangerous Goods

Regulations.

Hazardous, Restricted, and Perishable Mail

414 Publication 52

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September 7, 2023 415

Appendix F

Alaska Routes Serviced by

Air

Transportation Only

The following ZIP Codes in Alaska are only serviced by air transportation:

99545, 99546, 99547, 99548, 99549, 99550, 99551, 99552, 99553, 99554,

99555, 99557, 99558, 99559, 99561, 99563, 99564, 99565, 99569, 99571,

99574, 99575, 99576, 99578, 99579, 99580, 99581, 99583, 99585, 99589,

99590, 99591, 99602, 99604, 99606, 99607, 99608, 99609, 99612, 99613,

99614, 99615, 99619, 99620, 99621, 99622, 99624, 99625, 99626, 99627,

99628, 99630, 99632, 99633, 99634, 99636, 99637, 99638, 99640, 99641,

99643, 99644, 99647, 99648, 99649, 99650, 99651, 99653, 99655, 99656,

99657, 99658, 99659, 99660, 99661, 99662, 99663, 99665, 99666, 99667,

99668, 99670, 99671, 99675, 99677, 99678, 99679, 99680, 99681, 99682,

99684, 99685, 99689, 99690, 99691, 99692, 99695, 99697, 99720, 99721,

99722, 99723, 99724, 99726, 99727, 99730, 99732, 99733, 99734, 99736,

99738, 99739, 99740, 99741, 99742, 99745, 99746, 99747, 99748, 99749,

99750, 99751, 99752, 99753, 99754, 99756, 99757, 99758, 99759, 99761,

99762, 99763, 99765, 99766, 99767, 99768, 99769, 99770, 99771, 99772,

99773, 99774, 99777, 99778, 99781, 99782, 99783, 99784, 99785, 99786,

99788, 99789, 99790, 99791, 99801, 99802, 99803, 99811, 99812, 99820,

99821, 99824, 99825, 99826, 99827, 99829, 99830, 99832, 99833, 99835,

99836, 99840, 99841, 99850, 99901, 99903, 99918, 99919, 99921, 99922,

99923, 99925, 99926, 99927, 99928, 99929, 99950.

Hazardous, Restricted, and Perishable Mail

416 Publication 52

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September 7, 2023 417

Appendix G

Hazardous Materials Service Type Codes

(STCs) and Extra Service Codes (ESCs)

This appendix contains a complete list of Service Type Codes (STCs) and

Extra Service Codes (ESCs) to be applied within the tracking barcodes and

electronic data submission for shipments containing hazardous materials or

dangerous goods (See

323.2 and 323.3):

STCs Domestic Outbound (Required)

The following STCs are required when shipping domestic hazardous

materials, unless an STC from the “Optional” table is used:

760 Priority Mail Express Signature Waived – Hazardous Materials

116 Priority Mail USPS Tracking – Hazardous Materials

184 USPS Ground Advantage (up to 15.999 oz.) USPS Tracking –

Hazardous Materials

395 Parcel Select USPS Tracking –

Hazardous Materials

785 Parcel Select Lightweight USPS Tracking – Hazardous Materials

362 USPS Ground Advantage (one pound or more) USPS Tracking –

Hazardous Materials

STCs Domestic Outbound (Optional)

The following STCs are optional unless one of the applicable Extra Services

is selected when shipping domestic hazardous materials:

761 Priority Mail Express Signature Requested – Hazardous Materials

762 Priority Mail Express with Insurance – Hazardous Materials

763 Priority Mail Express with Insurance Restricted Delivery – Hazardous

Materials

764 Priority Mail Express Adult Signature Over 21 –

Hazardous Materials

120 Priority Mail Insurance <= $500 – Hazardous Materials

323 Priority Mail Insurance > $500 – Hazardous Materials

075 Priority Mail Adult Signature Over 21 – Hazar

dous Materials

063 Priority Mail Signature Confirmation Hazardous Materials

185 USPS Ground Advantage (up to 15.999 oz.) Insurance <= $500 –

Hazardous Materials

186 USPS Ground Advantage (up to 15.999 oz.) Insurance > $500 –

Hazardous Materials

Hazardous, Restricted, and Perishable Mail

418 Publication 52

STCs Domestic Returns (Required)

The following STCs for domestic hazardous materials returns packages are

required, unless an STC from the “Optional” list is used:

676 PRS - Hazardous Materials

187 USPS Ground Advantage Returns (up to

15.999 oz.) Insurance –

Hazardous Materials

385 USPS Ground Advantage (one pound or more) – Hazardous Materials

037 Priority Mail Return Service - Hazardous

Materials

217 USPS Ground Advantage Returns (up to

15.999 oz.) – Division 6.2

Hazardous Materials

218 USPS Ground Advantage Returns (one pound or more) – Division 6.2

Hazardous Materials

219 Priority Mail Return Service – Division 6.2 Hazardous Materials

859 PRS: HAZMAT – Division 6.2 Hazardous

Materials

STCs Domestic Returns (Optional)

The following STCs are optional for domestic hazardous materials returns

packages unless the applicable Extra Service is selected:

190 USPS Grounds Advantage Returns (up to 15.999 oz.) Insurance <=

$500 – Hazardous Materials

191 USPS Ground Advantage Returns (up to 1

5.999 oz.) Insurance > $500

– Hazardous Materials

388 USPS Ground Advantage Returns (one pound or more) Insurance <=

$500 – Hazardous Materials

399 USPS Ground Advantage Returns (one pound or more) Insurance >

$500 – Hazardous Materials

515 Priority Mail Return Service Insurance <= $500 – Hazardous Materials

517 Priority Mail Return Service Insurance > $500 – Hazardous Materials

678 PRS Insurance > $500 – Hazard

ous Materials

363 USPS Ground Advantage (one pound or more) Insurance <= $500 –

Hazardous Materials

365 USPS Ground Advantage (one pound or more) Insurance > $500 –

Hazardous Materials

166 USPS Ground Advantage (up to 15.999 oz.) Signature Confirmation –

Hazardous Materials

483 Parcel Select Insurance <= $50

0 – Hazardous Materials

628 Parcel Select Insurance > $500 – Hazardous Materials

646 Parcel Select Signature Confirmation Hazard

ous Materials

786 Parcel Select Lightweight Insurance <= $500 – Hazardous Materials

787 Parcel Select Lightweight Insurance >500 – Hazardous Materials

749 Parcel Select Lightweight Signatu

re Confirmation - Hazardous

Materials

Hazardous Materials Service Type Codes (STCs) and Extra Service Codes (ESCs)

September 7, 2023 419

ESCs Domestic (Optional)

The following is a list of category-specific ESCs that may be used in

conjunction with an STC if the mailer chooses:

810 Air Eligible Ethanol Package

811 Class 1 – Toy Propellant/Safety Fuse Package

812 Class 3 – Flammable Liquid Package

813 Class 7 – Radioactive Materials Package

814 Class 8 – Corrosive Materials Package

815 Class 8 – Nonspillable Wet Battery Package

816 Class 9 – Lithium Battery Marked – Ground Only Package

817 Class 9 – Lithium Battery – Returns Package

818 Class 9 – Lithium batteries, marked package

819 Class 9 – Dry Ice Package

820 Class 9 – Lithium batteries, unmarked package

821 Class 9 – Magnetized Materials Package

822 Division 4.1 – Flammable solids

and Safety Matches Package

823 Division 5.1 – Oxidizers Package

824 Division 5.2 – Organic Peroxides Package

825 Division 6.1 – Toxic M

aterials Package

826 Division 6.2 – Infectious Substances Package

827 Excepted Quantity Provision Package

828 Ground Only Hazardous Materials

829 ID8000 Consumer Commodity Package

830 Lighters Package

831 LTD QTY Ground Package

832 Small-Quantity Provision Package

ESCs Domestic and International,

including APO/FPO/DPO (Required)

The following ESCs must be provided for all shipments containing hazardous

materials or dangerous goods:

857 Hazardous Materials

Hazardous, Restricted, and Perishable Mail

420 Publication 52

ESCs International and APO/FPO/DPO

(Required)

The following is a list of ESCs required for use in the mailers Shipping Service

File, when tendering the following dangerous goods internationally with the

Postal Service:

813 Class 7 – Radioactive Materials Package

820 Class 9 – Lithium

batteries, unmarked package*

826 Division 6.2 – Infectious Substances Package

* The batteries must be installed in the equipment being shipped and must

not bear markings or labels identifying the contents as lithium batteries.

September 7, 2023 421

Index

Note: Any item with an asterisk (*) is NONMAILABLE under any conditions.

Abortive devices, see Unsolicited Promotional

samples

Acceptance procedures, 251, 726.1

Acetic acid, 348.22

Addressing, 221, 725.4

Adhesives, 343.24

Adult birds, 526.1, 526.43

Aerosols, 342.23

Air transportation requirements

Air carrier refusal, 727

Air only ZIP Codes, 722.2

General, 721

Markings, 725.2

Prohibitions, 327.2, 722.3

Sipper’s declaration, 326, 725.3

Alligators, baby, Exhibit 526.6

Ammunition*, 341.11, 341.21

Amphibians, Exhibit 526.6

Aniline oil*, 346.221

Animal-Fighting Ventures, 46

Definitions, 461

Mailability, 462

Animals (also see specific category or name of

animal)

Acceptance, 523

Air transportation, 742

Cold-blooded, see Cold-blooded animals

Disposal, 524

Dead, 526.7, Exhibit 526.7

General, 521

Illegal fish and wildlife, 57

Injurious animals, 57

International mail, 642

Mailable animals, 526

Marking, 522

Nonmailable animals, 525

Packaging, 522

Parts of, 526.7, Exhibit 526.7

Used for food, Exhibit 526.7

Antiseptics, 453.12

APO/FPO/DPO

Air transportation, 722.1

Hazardous materials, 621.4

Perishable matter, 641

Restricted matter, 631, 632.1

Appeals, 214

Aspirin, 453.12

Batteries, 348.21, 348.22

Alkaline, 348.21

Dry cell, 348.22

Liquid electrolyte*, 348.21

Lithium-ion, 349.222

Lithium metal, 349.221

Nonspillable wet, 348.22

Bees, 526.1, 526.2, Exhibit 526.21, 742.2

Biological product, 346.12, 346.233, 346.32

Biological products, aerosol, 342.23

Biohazard symbol, Exhibit 346.321

Black powder*, 341.11

Blasting caps*, 341.11

Blood, see Exempt animal specimen or Exempt

human specimen

Bloodworms, see Worms

Bombs, explosive*, 341.11

Bromoacetone*, 346.221

Bromobenzyl cyanide*, 346.221

Hazardous, Restricted, and Perishable Mail

422 Publication 52

Building construction material, 455

Bureau of Alcohol, Tobacco and Firearms, 341.22,

431.5, Exhibit 432.25, 433, 632.1, 632.2

Business Mail Acceptance office, 251

Butane, 342.23

Caimans, baby, Exhibit 526.6

Canaries*, 525.1

Canned heat, 343.24

Caps* (toy paper), 341.11

Carbon dioxide solid, see Dry ice

Carbonated beverages, 342.23

Cartridges* (primers and blanks), 341.21

Category B infectious substances, 346, 622.2

Cats*, 525.2

Caustic materials, see Corrosives

Cements, 343.24

Centers for Disease Control and Prevention (CDC),

215.1

Chameleons, Exhibit 526.6

CHEMTREC, 245

Chickens, see Poultry, day-old and Adult bird

Chlorine dioxide hydrate, frozen*, 345.21

3-Chloro-4-methylphenyl isocyanate*, 346.221

Chloroacetophenone*, 346.221

Chloropicrin*, 346.221

Cigarette lighter fluid, see Lighter fluid

Cigarette lighters, see Lighters

Cigarettes and smokeless tobacco, 47

Class, see Hazard Class

Cleaning agents, 343.24

Cockatiels*, 525.1

Cold remedies, 422.21, 453.12

Cold-blooded animals, small, harmless, 526.1,

526.6, Exhibit 526.6

Combustible liquids, 343, Exhibit 343.22

Definition, 343.1

Mailability requirements, 342.2

Mailable material, 343.24

Marking, 343.3

Nonmailable material, 343.23

Packaging, 343.2

Compressed gas, see Gases

Consumer Commodity, 333, Appendix D

Consumer Product Safety Act, 453.2

Contraceptive devices, see Unsolicited

promotional samples

Controlled substances act, 453.11

Controlled substances and drugs, 453

Definitions, 453.11

International mail, 636

Mailability requirements, 453.3

Mailer responsibility, 453.2

Marking, 453.4

Packaging, 453.4

Rulings, 453.5

Cooking wine, 422.21

Corrosives, 348

Definition, 348.1

Mailability requirements, 348.2

Mailable material, 348.22

Marking, 348.4

Nonmailable material, 348.21

Packaging, 348.3

Cremated remains, 451.22

Cyanogen bromide*, 346.221

Dangerous goods, 621.1

Day-old poultry, see Poultry, day-old

Dead animals, see Animals

Definitions, hazardous materials, Appendix D

Department of Energy (DOE), 347.5,

Exhibit 347.5c(1)

Department of Transportation (DOT), 321

Depressant drugs, see Controlled substances

Dermal toxicity, 346.11

Detonating fuse*, 341.11

Diagnostic specimen, see Exempt animal

specimen or Exempt human specimen

Diesel fuel, 343.24

Diet pills, 453.12

Diphenylamine chlorarsine*, 346.221

Diphenylchloroarsine*, 346.221

Disease germs, see Infectious substances

Dispatch procedures, 252, 726.2

Dogs*, 525.2

Doves, see Adult birds

Index

September 7, 2023 423

Drug paraphernalia, 453.13, 453.35

Drugs

Controlled substances, see Controlled

substances

International mail, 635

Marking, 453.4

Narcotic, 453.11, 453.31

Packaging, 453.4

Poisonous, see Toxic substances

Prescription, 453.12, 453.31, 453.32

Rulings, 453.5

Undeliverable medicines, 453.8

Drug Enforcement Agency (DEA), 453.31

Dry ice, 322, 349.1, 349.2, 349.23, 349.3,

Exhibit 526.7, 623, 743

Ducks, see Poultry, day-old and Adult birds

Dynamite*, 341.11

Dyes, 348.22

Eggs

Dried, whole, 643.2

Fresh, 54, 643.1

Electrolyte battery acid*, 348.21

Electronic tubes, 342.23

Etiologic agents, see Infectious substances

Emergency procedures

General, 24, 245, 246, 728

Radioactive material, 347.5

Emus*, 525.1

Environmental Protection Agency (EPA), 347.5

Ethanol-based liquids and solids, 343.27,

Appendix C

Excreta, see Exempt animal specimen or Exempt

human specimen

Exempt animal specimen, 346.326

Exempt human specimen, 346.326

Explosives*, 341

Compatibility codes, 341.12

Definition, 341.1

Mailability requirements, 341.2

Mailable material, 341.22

Nonmailable material, 341.21

Extinguishers, see Fire extinguishers

Federal Emergency Management Agency (FEMA)

347.5

Finches, 525.1

Fire alarm systems, audible, 342.23

Firearms,

Antique, 431.3

Export, 632.1

Found in mail, 435

General, 43, Exhibit 432.25

Import, 632.2

International mail, 632

Legal opinion, 433

Manufacturer/Dealer, 431.5

Marking, 432.3

Firecrackers*, see Fireworks

Fire extinguishers, 342.22, 342.23

Fireworks*, 341.11, 341.21

Fish, Exhibit 526.6, Exhibit 526.7

Flammable gas, see Gases

Flammable liquid, 343

Definition, 343.1

Mailability requirements, 343.21, Exhibit 343.21

Mailable material, 343.24

Marking, 343.3

Nonmailable material, 343.23

Packaging, 343.2

Flammable solid, 344

Definition, 344.1

Mailability requirements, 344.2

Mailable material, 344.2

Marking, 344.3

Nonmailable material, 344.21

Packaging, 344.3

Flashpoint, 343.1, Exhibit 343.21, Exhibit 343.22,

Appendix D

Flying squirrels*, 525.2

Foodstuffs, aerosol products, 342.23

Food

Eggs, see Eggs

Fresh foods, 53, 645

Meats, see Meat

Fountains, cylindrical and cone (fireworks)*, see

Fireworks

Form 1508, 432.24

Friction-top closure, 451.3

Hazardous, Restricted, and Perishable Mail

424 Publication 52

Frogs, Exhibit 526.6

Fruits, fresh, see Foods

Fuel

Diesel, see Diesel fuel

Model, see Model fuel

Oil, see Fuel oil

Fuel oil, 343.24

Fuses*, 341.21

Fusees*, 341.22

Game birds, for food use, Exhibit 526.7

Gases, 342

Definition, 342.1

Empty containers, 342.23

Mailability requirements, 342.2

Mailable gases, 342.23

Marking, 342.4

Nonmailable gases, 342.22

Toxic*, 342.22

Packaging, 342.3

Tear gas, see Tear gas

Gasoline*, 343.23

Geese, see Poultry, day-old and Adult birds

Germs, see Infectious substances

Goldfish, see Fish

Grenades*, 341.11

Guinea birds, see Poultry, day-old and Adult birds

Guinea hens, see Guinea birds

Guinea pigs*, 525.2

Gun Control Act, 431.5, 432.1, Exhibit 432.25

Guns, see Firearms

Hallucinogenic drugs, see Controlled substances

Hamsters*, 525.2

Handguns*, 431.2, Exhibit 432.25

Handling, see Dispatch procedures

Hazard Class, 331, Exhibit 331, 34, 621.2,

Exhibit 621.1

Hazard Class 1, see Explosives

Hazard Class 2, see Gases

Hazard Class 3, see Flammable liquids and/or

Combustible liquids

Hazard Class 4, see Flammable solids

Hazard Class 5, see Oxidizing substances and/or

Organic peroxides

Hazard Class 6, see Toxic Substances and/or

Infectious Substances

Hazard Class 7, see Radioactive materials

Hazard Class 8, see Corrosives

Hazard Class 9, see Miscellaneous hazardous

materials

Hazardous materials

Air transportation, 72, 721

Definition, 31, Appendix D

General, 122, 211

Handling, 23

International mail, 621, 622, 623

Table, 328, Appendix A, Appendix B

Warning labels, see Labels

Health and Human Services (HHS) Department,

see Centers for Disease Control and Prevention

(CDC)

Hellgrammites, Exhibit 526.6

Herbicides, 346, 346.232

Hexaethyl tetraphospate, liquid or solid*, 346.221

Honeybees, see Bees

Hydrochloric acid, 348.22

Hydrocyanic acid, aqueous solutions*, 346.221

Hydrofluoric acid, 348.21

Hydrogen peroxide, 345.1, 345.21, 345.22

Ice

Dry, see Dry ice

Water, Exhibit 526.7

Identification number, see UN number or NA

number

Igniters, 341.22

Inert devices, 434

Infectious substances, 346

Biological products, 346.12

Definition, 346.1, 346.12

International mail, 622

Mailability requirements, 346.212

Mailable material, 346.23, 346.233

Marking, 346.32

Nonmailable material, 346.22

Other medical waste, see Used medical

devices

Index

September 7, 2023 425

Packaging, 346.32

Sharps, see Sharps

Specimen, see Exempt animal specimen or

Exempt human specimen

Inhalation toxicity, 346.11

Inks, 343.26

Insecticides, 346.232

Insects

Dead, dried, 526.7, 642

International mail, 642

Nonpoisonous, Exhibit 526.6

Poisonous, 525.4

International mail 6

Biological substances, 622.2

Magnetized materials, 622.4

Nonmailable materials, 623

Radioactive materials, 622.3

Intoxicating liquors, 42

Irritating materials*, 346.11, 346.221

Keys, see Motor vehicle master keys

Kittens*, 525.2

Knives and sharp instruments, 44, 441, 442, 443,

634

Label 27, 225

Label 28, 225

Label 127, 225

Labeling requirements (See requirements for

specific items)

Labels

Biohazard materials, 346.321

DOT warning labels, 223, 325, Exhibit 325.3a,

Exhibit 325.3b, Exhibit 325.4, 723

Dry ice, 349.23

Infectious substances, Exhibit 346.321

International mail, 622.2, 622.3

Magnetized materials, Exhibit 349.242b

Refusal by aricraft, 711.2

Latex paint, see Paint

Leeches, Exhibit 526.6

Light meters, see Magnetized materials

Lighter fluid, 343.24

Lighters, 342.22, 343.25

Limited quantity, 332, Appendix D

Liquids

Corrosive, 348

Flammable, 343

Toxic, 346

Liquids and Powders, nonhazardous, 451

cremated remains, 451.22

Liquors, see Intoxicating liquors

Lizards, Exhibit 526.6

Locksmithing devices, 452

Magnetized materials, 349.1, 349.2, 349.21,

349.24, Exhibit 349.242b, 349.3, 622.4

Magnetrons, see Magnetized materials

Mailability, 123, 211, 213, 322

Mailability rulings, see Rulings

Mailable limited quantity, 334

Mailer responsibility, 13, 212, 323, 725

Markings

Excepted matter, 222

General, 221, 223

Old, 227

Orientation, 226

Small quantity, 336

Matches, 344.3

Material Safety Data Sheet (MSDS), see Safety

Data Sheet

Mealworms, see Worms

Meat and meat products, 55, 645

Medical preparations (aerosol), 342.23

Medical waste, see Sharps or Used medical

devices

Medicines, see Drugs

Medicines, poisonous, see Toxic substances

Mercury fulminate*, 341.11

Methyl bromide*, 346.221

Methyl parathion, liquid*, 346.221

Microorganisms, 346.12

Mice*, 525.2

Military Postal System, 16

Miscellaneous Hazardous Materials, 349

Model fuel, 343.24

Hazardous, Restricted, and Perishable Mail

426 Publication 52

Motor fuel antiknock mixtures*, 346.221

Motor vehicle master keys, 452

Mouthwash, 422.21

MSDS, see Material safety data sheet

NA number, 215.2, Appendix A, Appendix D

Narcotic drugs, see Controlled substances

Newts, Exhibit 526.6

Nitric acid*, 348.21

Nitroglycerine, desensitized*, 341.11

Nonmailable matter

Air transportation, 727.1

Found in mail, 216

General, 216

Hazardous materials, 34, 623

Restricted matter, 414, 422.11, 435, 444,

452.4, 453.6

Perishable matter, 525

North American number, see NA number

Nuclear Regulatory Commission (NCR), 347.5

Odor-producing materials, 451

Odors, obnoxious, 122, 521

Old markings, see Markings

Oral toxicity, 346.11

Orientation markings, see Markings

Organic peroxides, 345

Organic phosphate compound*, 346.221

ORM-D, 335, 621.3, Appendix D

Oxidizing substances, 345

Oxygen

Compressed, 342.23

Refrigerated liquid*, 342.22

Packaging requirements, 339 (also see individual

listings for each hazard class)

Packaging Instructions, see USPS Packaging

Instructions,

Appendix C

Packing groups, 339.1

Paint and paint-related materials, 343.24, 343.26

Paint products, aerosol, 342.23

Parakeets*, 526.4

Parasites, see Insects and Plants

Parathion, 346.221

Parrots*, 526.4

Partridges, see Poultry, day-old and Adult birds

Perchloric acid*, 345.21

Perishable matter

Air transportation, 74

Definition, 51

General, 122, 215.3

International, 64

Pesticides, 346, 346.232

Pheasants, see Poultry, day-old and Adult birds

Phenylcarbylamine chloride*, 346.221

Photographic mixtures, 348.22

Pigeons*, see Adult birds

Pistol*, see Handgun

Plants

General, 56

International mail, 644

Plant Pests, 571, 562

Quarantine, 562, 644

Poison Prevention Packaging Act, 453.2

Poisons

Definition, 3

Nonclassified toxic materials, 3

Primary mailability considerations, 3

Polishes, 343.24

Potassium peroxide*, 345.21

Poultry, day-old, 526.1, 526.3, Exhibit 526.33

Powder

Explosive*, 341

Nonhazardous, see Liquids and Powders

Prescription drugs and medicines, see Drugs

Pricing and Classification Service Center (PCSC),

213, 214

Primers (small arms ammunition)*, 341.21

Promotional samples, see Unsolicited promotional

samples

Propane, 342.23

Propellant devices, see Toy propellant devices

Propellants, liquid and solid*, 341.11

Puppies*, 525.2

Pyrotechnic wheels*, see Fireworks

Index

September 7, 2023 427

Quail, see Poultry, day-old and Adult birds

Quarantined plants, 562, 644

Queen bees, see Bees

Rabbits*, 525.2

Radioactive materials, 347

Articles and instruments, Exhibit 347.22

Emergency procedures, 347.5

International mail, 622.3

Rats*, 525.2

References, 113, Appendix E

Replica devices, 434

Reptiles

Nonpoisonous, Exhibit 526.6

Poisonous*, 525.3

Restricted matter, 122, 211, 4, 411, 63, 637, 73

Revolver*, see Handgun

Rifles, 431.4. Exhibit 432.25

Rocket motors*, 341

Rockets, helicopter-type*, see Fireworks

Roman candles*, see Fireworks

Ruling authority 213

Rulings

Gases, 342.5

General 215

Hazardous materials, 215.2, 324

Perishable matter, 215.3

Restricted matter, 215.3, 413, 453.5, 454.5

Safety, 14

Safety Data Sheet (SDS), 215.2, Appendix D

Safety fuses, 322, 341.22

Safety matches, see Matches

Salamanders, Exhibit 526.6

Salt, used as preservative, Exhibit 526.7

Salutes*, see Fireworks

Samples, unsolicited promotional, see Unsolicited

promotional samples

Scabs, see Infectious substances

Scorpions, live, 526.1, 526.5, Exhibit 526.5

Sharps, medical, 346.12, 346.212, 346.222,

346.233, 346.322

Sharp instruments, see Knives

Shipper’s declaration for dangerous goods, see

Shipping papers

Shipping papers, 228, 326, Exhibit 326, 725.3

Short-barreled rifle, 431.2

Short-barreled shotgun, 431.2

Shotgun casings, hulls, 341.22

Shotguns, 431.4, Exhibit 432.25

Silkworms, see Worms

Skyrockets*, see Fireworks

Small arms ammunition*, see Ammunition

Small quantity, 336, Appendix D

Snails, Exhibit 526.6

Snakes*, 526.6

Sodium chlorite*, 345.21

Sodium picramate*, 341.11

Solids

Corrosive, see Corrosives

Flammable, see Flammable solids

Nonregulated toxic material, 346.232

Solvents, 343.24

Sparklers, see Fireworks

Specimen, see Exempt animal specimen or

Exempt human specimen

Specification packaging, Appendix D

Spiders*, poisonous, 525.4

Squirrels, flying*, 525.2

Statutory system, 17

Sterno, see Canned heat

Stimulant drugs, see Controlled substances

Sulfuric acid, 348.21, 348.22

Swans, see Adult birds

Switchblade knives, see Knives

Tadpoles, Exhibit 526.6

Tag 9, 225

Tag 44, 224

Tear gas*, 346.221

Tetraethyl dithiopyrophosphate*, 346.221

Tetraethyl lead liquid*, 346.221

Tetraethyl pyrophosphate liquid*, 346.221

Tetranitromethane*, 345.21

Thiophosgene*, 346.221

Hazardous, Restricted, and Perishable Mail

428 Publication 52

Tissue, tissue fluids, see Infectious substances

Toads, Exhibit 526.6

Torches, illuminating*, see Fireworks

Tortoises*, see Turtles

Toy propellant devices, 322, 341.22

Toxic substances, 346

Nonmailable material, 346.22

Nonregulated toxic materials, 346.232

Poisonous drugs, 346.231, 453.33

Toxin, see Toxic substances

Transportation requirements, 327, 7

Trick matches*, see Matches

Tropical fish, see Fish

Turkeys, see Poultry, day-old and Adult birds

Turtles*, 525.3, 526.6

Turtle eggs*, 526.6

UN number, 215.2, Appendix A, Appendix D

United Nations number, see UN number

United States Department of Agriculture (USDA),

55, 562, 564

Unsolicited promotional samples, 454

Abortive and contraceptive devices, 454.221

Certificate compliance, 454.3

Customer objection, 454.4

Nonmailable matter, 454.22

Rulings, 454.5

Used medical devices, other, 346.12, 346.212,

346.222, 346.233, 346.32

USPS Packaging Instructions, Appendix C

Vegetables, fresh, see Foods

Waxes, 343.24

Wildlife, see Animals

Worms

Bloodworms, Exhibit 526.6

Mealworms, Exhibit 526.6

X, Y, Z

Zinc ammonium nitrite*, 345.21