CFR›Title 46›Chapter I›Part 53›Subpart 53.05 ContainsSections 53.05-1–53.05-5CorpusDaily eCFRDisplayed edition2026-09-01Last updated2026-09-01 Subpart 53.05—Pressure Relieving Devices (Article 4) Sections 53.05-1 § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). 53.05-2 § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). 53.05-3 § 53.05-3 Materials (modifies HG-401.2). 53.05-5 § 53.05-5 Discharge capacities and valve markings. SourceCGD 81-79, 50 FR 9435, Mar. 8, 1985, unless otherwise noted. Previous 53.01 Subpart 53.01—General Requirements Next 53.10 Subpart 53.10—Tests, Inspection, Stamping, and Reporting (Article 5)