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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 instruction 10A is for the small quantity provision cited in 336. Postal Service packaging instructions are provided as follows:

Hazard Class 1: Explosives

Hazard Class 2: Gases

Hazard Class 3: Flammable and Combustible Liquids

Hazard Class 4: Flammable Solids

Hazard Class 5: Oxidizing Substances, Organic Peroxides

Hazard Class 6: Toxic Substances and Infectious Substances

Hazard Class 7: Radioactive Materials

Hazard Class 8: Corrosives

Hazard Class 9: Miscellaneous Hazardous Materials

Category 10: Other Packaging Instructions