Hazardous, Restricted, and Perishable Mail – Updated Publication 52

Publication 52 provides important information to help mailers determine what may be mailed
and how certain items must be packaged to keep the mail safe. It also provides guidance to
Postal Service employees accepting this mail.

Click to Download Publication 52

Issued February 2026, this policy supersedes the June 2025 edition, edition of Publication 52

Summary of Major Changes:

 Eliminated the COVID Test Kit Authorization Requirement.
 Correct external regulatory and internal publication references.
 Delete lithium-battery telephone number marking requirements in the domestic
packaging instructions in accordance with new Postal Service standards.
 Update entries in Appendix A pertaining to lighters and regulated medical waste.
 Clarify that the maximum weight is 35 pounds for container testing under the
medical professional packages category regarding regulated medical waste.