3 Hazardous Materials 3 Hazardous Materials
31 Definition
32 General
321 U.S. Department of Transportation
322 Postal Service
323 Mailer Responsibility
323.1 General
323.2 Service Type Codes
323.3 Extra Service Codes
323.4 Shipping Service File
323.5 Legacy Postage and Hard-Copy Postage Statements
324 Mailability Rulings
325 Hazardous Materials Warning Labels, Markings, Tags, and Endorsements
325.1 General Requirements
325.2 Ancillary Endorsements
325.3 Nonmailable DOT Warning Labels and Marks
325.4 Mailable Warning Labels
325.5 Limited Quantity Markings
325.6 Excepted Quantity Labels
326 Shipping Documentation
327 Transportation Requirements
327.1 General
328 Postal Service Hazardous Materials Table
329 Presentation of Hazardous Materials Mailing
33 Hazard Classes
331 Nine Classes
332 Limited Quantity
333 Consumer Commodity
334 Limited Quantity Air Materials
335 ID8000 Materials
336 Limited Quantity Surface Materials
337 Excepted Quantity
337.1 Definition
337.2 Mailability
337.3 Additional Restrictions
337.4 Quantities
337.5 Packaging and Marking
338 Small Quantity
338.1 Definition
338.2 Mailability
338.3 Additional Restrictions
338.4 Quantities
338.5 Packaging and Marking
339 Packaging Requirements for Hazardous Materials
339.1 DOT Packing Groups
339.2 Postal Service Packaging Instructions
339.3 USPS-Produced Packaging
339.4 Hazardous Materials Outer Packaging
34 Mailability by Hazard Class
341 Explosives (Hazard Class 1)
341.1 Definition
341.2 Mailability, Packaging, and Marking
342 Gases (Hazard Class 2)
342.1 Definition
342.2 Mailability
342.3 Packaging
342.4 Marking and Documentation
342.5 Mailability Rulings
343 Flammable and Combustible Liquids (Hazard Class 3)
343.1 Definition
343.2 Mailability and Packaging
343.3 Marking and Documentation
344 Flammable Solids (Hazard Class 4)
344.1 Definition
344.2 Mailability
344.3 Packaging, Marking, and Documentation
344.4 Nonmailable Flammable Solids
345 Oxidizing Substances, Organic Peroxides (Hazard Class 5)
345.1 Definition
345.2 Mailability
345.3 Packaging, Marking, and Documentation
345.4 Nonmailable Class 5 Materials
346 Toxic Substances and Infectious Substances (Hazard Class 6)
346.1 Definitions
346.2 Division 6.1, Toxic Substances Mailability
346.3 Division 6.2, Infectious Substances Mailability
346.4 Damaged Packages
347 Radioactive Materials (Hazard Class 7)
347.1 Definition
347.2 Mailability
347.3 Packaging
347.4 Marking
347.5 Emergency Procedures
348 Corrosives (Hazard Class 8)
348.1 Definition
348.2 Mailability
348.3 Packaging
348.4 Marking and Documentation
349 Class 9 Hazardous Materials
349.1 Mailability
349.2 Lithium Batteries
349.3 Dry Ice
349.4 Magnetized Materials
349.5 Marking, Packaging, and Documentation
349.6 Nonmailable Class 9 Materials