49 CFR §179.201-4
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
All fittings, tubes, and castings and all projections and their closures, except for protective housing, must also meet the requirements specified in ASTM A 262 (IBR, see § 171.7 of this subchapter), except that when preparing the specimen for testing the carburized surface may be finished by grinding or machining.