Postal Explorer > Publication 52 - Hazardous, Restricted, and Perishable Mail > Appendix C USPS Packaging Instructions for Mailable Hazardous Materials > USPS Packaging Instruction 1B

USPS Packaging Instruction 1B

Safety Fuse

Safety fuses consist of a core of black powder overspun with yarns, waterproofing compounds, and/or tapes. A safety fuse assigned identification number UN0105 and classed as a Division 1.4S explosive may be mailed only as permitted in 341.22b and when properly packaged as follows.

Proper Shipping Name

• Safety Fuse.

ID Number

• UN0105.

Required Authorization

• Prior written permission must be obtained from the Manager, Mailing Standards, USPS Headquarters, Washington, DC (see DMM 608.8 for mailing address).

Mailability

• International Mail: Prohibited.

• Domestic Mail: Permitted only via surface transportation sent as Standard Mail or Parcel Post with prior approval.

Required Packaging

Primary Receptacle

• Each device must be packed in a securely sealed primary receptacle.

• Multiple primary receptacles are permitted within a single mailpiece.

Cushioning Material

• Each primary receptacle must be surrounded by sufficient cushioning material to absorb shock and prevent breakage.

Outer Packaging

• A strong outer packaging that is capable of firmly and securely holding the primary receptacle(s) and cushioning material is required.

• The outer packaging must be made of fiberboard, wood, or metal. Friction closures or paperboard containers are not acceptable.

Marking

• The outside of the mailpiece must be clearly marked on the address side with "Safety Fuse, UN0105" and "Surface Only" or "Surface Mail Only".

• A complete mailing address and return address must be used.

Documentation

• A properly completed shipper's declaration for dangerous goods must be prepared in triplicate, and affixed to the outside of the mailpiece.

Note: Full responsibility rests with the mailer to comply with DOT and ATF regulations before mailing. A legible photocopy of the Mailing Standards Manager's approval letter must be presented by the mailer to the Postal Service acceptance clerk at the time of mailing.