Publication 52 - Hazardous, Restricted, and Perishable Mail > Appendix C > USPS Packaging Instruction 6F Forensic material containing a biological material, such as tissue, body fluid, excreta, or secreta, and sent on behalf of a federal, state, local, or Indian tribal government agency must be packaged under 346.325 when it is not known or suspected to contain a Category A or Category B infectious substance. Forensic material known or suspected to contain a Category A infectious substance is not mailable. Forensic material known or suspected to contain a Category B infectious substance as identified in 346.321 is mailable via air transportation, when triple-packaged in a primary receptacle, secondary container, and a rigid outer shipping container. Substances identified in IMM 135.11b must be sent only by authorized laboratories to their foreign counterparts in those countries that have indicated a willingness to accept them. Note: Countries distinguish between infectious and noninfectious (nonregulated) biological substances and may prohibit one or the other or both. See “Prohibitions” in the Individual Country Listings. | |