49 CFR § 179.201-4
Material
November 18, 2020
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.
[68 FR 75762, Dec. 31, 2003]