Last amended:2016Year:2026Length:67 wordsSubsections:2Official source
Cite as 49 C.F.R. § 179.200-21 (2026)
(a) All plugs shall be solid, with NPT threads, and shall be of a length which will screw at least 6 threads inside the face of fitting or tank. Plugs, when inserted from the outside of tank heads, shall have the letter “S” at least
3/8
inch in size stamped with steel stamp or cast on the outside surface to indicate the plug is solid.
(b) [Reserved]