334 USPS Limited Quantity Air Materials | Postal Explorer

334 USPS Limited Quantity Air Materials

The USPS Limited Quantity Air classification applies to certain hazardous materials within Hazard Classes 5, 8, and 9 that are permitted specifically in the Postal Service for air transport. The Limited Quantity air category and marking may be used in domestic mail only and is prohibited in international mail.

It is the responsibility of the mailer to know the correct DOT hazard class of a hazardous material before mailing (see 323).

When assistance is needed to determine eligibility for mailing, the mailer may request a ruling from the PCSC as outlined in 215.