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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 can qualify as a consumer commodity or ORM-D material, and all applicable requirements in 343 are met.

Flammable liquids having a flashpoint of 20° or less are not mailable.

Flammable liquids mailed under DOT-SP 9275 must be prepared and marked as specified in 343.27 or DMM 601.10.13.5.

Proper Shipping Name

ID Number

Mailability

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
Cushioning Material and Secondary Packaging
Outer Packaging
Marking
For flashpoint greater than 73º F (23º C) but less than 100º F (38º C):
Primary Receptacle
Cushioning Material and Secondary Packaging
Outer Packaging
Marking
For flashpoint of at least 100º F (38º C) but not more than 141º F (60.5º C):