Cylinder Special Permit List (PHMSA)

PHMSA/DOT High-Presuure Cylinder Special Permit List

Special permits get updated and reissued regularly, so before you sign off on an inspection, confirm you’re referencing the current version — not an outdated copy saved from a previous job.

The button above links directly to PHMSA’s official Special Permits list. It’s organized by SP number range, and it covers every category of hazmat special permit — not cylinders exclusively — so have the SP number stamped or labeled on the cylinder ready before you search. Looking for a grantee (“party to”) letter instead of the base permit? PHMSA also runs a separate search tool by SP number, company name, or state, linked from that same page.