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USPS Packaging Instruction 3B

Combustible Liquids

A combustible liquid having a flashpoint of 141° F (60.5° C) but no more than 200° F (93° C) is mailable if it can qualify as a consumer commodity or
ORM-D material and meet all applicable requirements in 343. A flammable liquid having a flashpoint of at least 100° F (38° C) but not more than 141° F (60.5° C) may be reclassed as a combustible liquid within the limits of 49 CFR 173.120(b).

Proper Shipping Name

ID Number

Mailability

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 141º F (60.5º C):
General
Primary Receptacle
Absorbent and Cushioning Material
Secondary Packaging
Outer Packaging
Marking
For flashpoint above 141º F (60.5º C) but not more than 200º F (93º C):
General
Primary Receptacle
Absorbent and Cushioning Material
Secondary Packaging
Outer Packaging
Marking
Documentation
For flashpoint above 200º F (93º C):
General
Primary Receptacle
Absorbent and Cushioning Material
Outer Packaging
Marking