Publication 52 - Hazardous, Restricted, and Perishable Mail > Appendix C > USPS Packaging Instruction 2C A fire extinguisher containing a Division 2.2 compressed, nonflammable gas assigned UN1044 that can qualify as a Limited Quantity surface material is mailable if it does not contain a methyl bromide gas mixture or sulfuric acid, and, if the gas is nonflammable, nonpoisonous, or noncorrosive, as specified in 49 CFR § 173.309(a). All applicable requirements in 342 must be met, and it must be properly packaged as follows. The following labels and text markings must be placed on the address side of the mailpiece unless specified in 325.1. Note: Fire extinguishers assigned UN0275, UN0276, UN0323, and UN0381 are prohibited from mailing. However, fire extinguishers assigned UN1774 are mailable as Class 8 corrosives subject to the limitations for corrosives in 348. | |