Transmittal Letter

Hazardous, Restricted, and Perishable Mail

Document Category

This document 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.

Chief Customer and Marketing Officer and Executive Vice President

Summary of Major Changes

This policy supersedes the September 7, 2023, edition of Publication 52, Hazardous, Restricted, and Perishable Mail.

Restructured the document and headings to be easier to navigate and locate specific information through combining sections based on mailing requirements.
Language has been simplified and strengthened to clarify mailer responsibilities when packaging, marking, labeling, documenting, and submitting hazardous, restricted, or perishable material for mailing and shipping.
Clarified the use of shipping documentation, Shipper‘s Declaration of Dangerous Goods, and shipping papers in domestic and international mail.
Postal Service requirements have been updated to align with the most recent Department of Transportation regulations.
Other Postal Service requirements regarding the PACT Act exceptions in sections 473.3 and 473.4 have been amended to permit shipments to be sent utilizing USPS Ground Advantage in addition to Priority Mail Express and Priority Mail.
USPS product offerings updated to reflect the removal of Parcel Select Lightweight and the addition of USPS Ground Advantage.
Added new requirements for specific outer packaging strength standards when mailing hazardous materials or dangerous goods.
Removed quantity restrictions for nonregulated toxic materials and certain labeling requirements for lithium batteries.

This document is available for Postal Service employees at http://blue.usps.gov.

Address questions about this policy to the owner.

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