{"data":{"id":"us/49-cfr-179.300-17","jurisdiction":"us","citation":"49 CFR 179.300-17","heading":"-17 Tests of pressure relief devices.","body":"(a) Each valve shall be tested by air or gas before being put into service. The valve shall open and be vapor-tight at the pressure prescribed in § 179.301.\n(b) Rupture disks of non-reclosing pressure relief devices must be tested and qualified as prescribed in appendix A, Paragraph 5, of the AAR Manual of Standards and Recommended Practices, Section C—Part III, AAR Specifications for Tank Cars (IBR, see § 171.7 of this subchapter).\n(c) For pressure relief devices of the fusible plug type, a sample of the plug used shall function at the temperatures prescribed in § 179.300-15.\n(d) The start-to-discharge and vapor-tight pressures shall not be affected by any auxiliary closure or other combination.","path":["Title 49—Transportation","Subtitle B—Other Regulations Relating to Transportation","CHAPTER I—PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","SUBCHAPTER C—HAZARDOUS MATERIALS REGULATIONS","PART 179—SPECIFICATIONS FOR TANK CARS","Subpart E—Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW)"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-49.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:34Z","sha256":"e727138b0251e7e6fba9aa41b7f04175968e9bbc10e8c4782e0cd338dde474f9","source_id":"us-cfr","stale":true,"prev":"us/49-cfr-179.300-16","next":"us/49-cfr-179.300-18"},"notice":"GroundRules: Original legal text. Not legal advice."}