49 C.F.R. § 179.400-21 Test of pressure relief valves.
Title 49 - Transportation
Each valve must be tested with air or gas for compliance with §179.401–1 before being put into service.
Title 49: Transportation
PART 179—SPECIFICATIONS FOR TANK CARS
Subpart F—Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A)
§ 179.400-21 Test of pressure relief valves.
