US lawFederal (United States)RegulationsTitle 49 CFR — TransportationChapter I — PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATIONPart 179 — SPECIFICATIONS FOR TANK CARSSubpart E — Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW)179.300-449 C.F.R. § 179.300-4Insulation.Last amended: 2016Year: 2026Length: 8 wordsSubsections: 2Official source Cite as 49 C.F.R. § 179.300-4 (2026)(a) Tanks shall not be insulated. (b) [Reserved]Next49 C.F.R. § 179.300-6