Code of Federal Regulations Title 46. Shipping § 46.53.01–10 Service restrictions and exceptions (replaces HG–101)

(1) Boilers of wrought materials shall be restricted to a maximum of 103 kPa gage (15 psig) for steam and a maximum of 689 kPa (100 psig) or 121°C (250°F) for hot water. If operating conditions exceed these limits, design and fabrications shall be in accordance with part 52 of this subchapter.

(2) Boilers of cast iron materials shall be restricted to a maximum of 103 kPa gage (15 psig) for steam and to a maximum of 206 kPa gage (30 psig) or 121°C (250°F) for hot water.

(1) Electrically fired hot water supply boilers that have a capacity not greater than 454 liters (120 gallons), a heat input not greater than 58.6 kilowatts (200,000 BTU per hour), and are listed as approved under Underwriters' Laboratories UL 174 or UL 1453 (both incorporated by reference;  see 46 CFR 53.01–1) are exempted from the requirements of this part provided they are protected by a pressure relief device. This relief device need not comply with § 53.05–2.

(2) Oil fired hot water supply boilers shall not be exempted from the requirements of this part on the basis of size or heat input.

(1) Be stamped with the appropriate ASME Code symbol in accordance with PG–104 through PG–113 of section IV of the ASME Boiler and Pressure Vessel Code;

(2) Meet the service restrictions of § 53.01–10(b)(2) if made of cast iron;

(3) Have safety valves which meet the requirements of § 52.01–120 of this subchapter;

(4) If a hot water supply boiler, have a temperature relief valve or a pressure-temperature relief valve in accordance with § 53.05–2(c);

(5) If automatically controlled, meet the applicable requirements in part 63 of this subchapter;  and

(6) Meet the inspection and test requirements of § 53.10–3.