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 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 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.

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

• Each mailpiece must be plainly and durably marked on the address side with “Surface Only” or “Surface Mail Only” and “Consumer Commodity ORM–D.”
• Optionally each mailpiece may bear the appropriate DOT limited quantity square-on-point marking, prepared under 343.3b, instead of an ORM-D marking.
• A complete return address 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.

Outer Packaging

• Strong outer packaging that is capable of firmly and securely holding the primary receptacles, cushioning material, and secondary packaging is required.

Marking

• When permitted for air transportation, packages must bear the DOT square-on-point marking including the symbol “Y,” an approved DOT Class 9 hazardous material warning label, Identification Number “ID8000,” and the proper shipping name “Consumer Commodity.”
• When using surface transportation, each mailpiece must bear an approved DOT limited quantity square-on-point marking, designating surface transportation, and prepared under 343.3b, or be plainly and durably marked on the address side with “Surface Only” or “Surface Mail Only” and “Consumer Commodity ORM–D.”
• 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.

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.