Subpart A—Introduction, Approvals and Reports8Subpart B—General Design Requirements11Subpart C—Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120)31Subpart D—Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW, 115AW, and 117AW)69Subpart E—Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW)20Subpart F—Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A)44
Regulationcurrent
49 CFR 179.100-17
-17 Closures for openings.
Current as of 2026-08-18 Government source
eCFR editorial compilationAuthoritative but unofficial
(a)Closures shall be of approved design and made of metal not subject to rapid deterioration by the lading. Plugs, if used, shall be solid, with NPT threads, and shall be of a length which will screw at least six threads inside the face of fitting or tank.#
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