The minimum safety valve relieving capacity for Low Pressure/Heating Boilers and other heat storage sources shall be determined in accordance with the 2019 ASME Boiler and Pressure Vessel Code Section IV, Rules for Construction of Heating Boilers.
For services exceeding these limits, the rules of the 2017 ASME Boiler and Pressure Vessel Code Section I, Rules for Construction of Power Boilers and 522 CMR 16.00: Controls and Safety Devices for Automatically Fired Boilers (ASME Code CSD-1-2015), Part CG: General, Part CM: Maintenance and Testing, Part CW: Steam and Waterside Control apply.
Boilers within the scope of 522 CMR 4.00 which were legally operating in the Commonwealth prior to January 1, 1978 and which conformed to the existing installation rules may continue in such service.
522 CMR, § 4.01