Section 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401)(a) The pressure relief valve requirements and the safety valve requirements for steam boilers must be as indicated in HG-400 and HG-401 of Section IV of the ASME BPVC (incorporated by reference; see § 53.01-1 ) except as noted otherwise in this section.(b) Each steam boiler must have at least one safety valve.CGD 81-79, 50 FR 9435, Mar. 8, 1985, as amended by USCG-2003-16630, 73 FR 65163 , Oct. 31, 2008