400. REQUIREMENTS FOR LICENSED OPERATORS

400 REQUIREMENTS FOR LICENSED OPERATORS 400.1 The operation and maintenance of the following equipment shall be exempt from the requirement of having licensed operating engineers: (a) Vehicles operated under the regulations of the D.C. Public Service Commission or the U.S. Interstate Commerce Commission; (b) Machinery on boats or vessels operated under the regulations of the United States Coast Guard; (c) Automotive vehicles used solely for traction purposes; (d) Packaged, self-contained air conditioning units; (e) Automatically operated air conditioning systems with non-toxic and non-inflammable refrigerant and not over a total of one hundred twenty-five (125) compressor horsepower, where no one refrigerant circuit is in excess of seventy-five (75) horsepower; (f) Automatically operated air conditioning systems using the heat absorption cycle with a non-toxic and non-inflammable refrigerant and not over a total of one hundred twenty-five (125) tons of refrigeration, where no one refrigerant circuit is in excess of seventy-five (75) tons, except where a boiler of a type and capacity that requires a licensed engineer is used; (g) Cold storage and refrigeration systems using non-toxic and non-inflammable refrigerant not in excess of seventy-five (75) compressor horsepower; (h) Cold storage and refrigeration systems using the heat absorption cycle with a non-toxic and non-inflammable refrigerant not in excess of forty (40) tons; (i) Cold storage and refrigeration systems using toxic or inflammable refrigerant not in excess of five (5) compressor horsepower; (j) Cold storage and refrigeration systems using the heat absorption cycle with a toxic or inflammable refrigerant not in excess of three (3) tons; (k) Automatically operated pumping stations; (l) Hot water heating boilers where the total boiler horsepower is not in excess of seventy-five (75) horsepower [sixteen thousand eight hundred square feet (16,800 ft.2) of water radiation at one hundred fifty degrees Fahrenheit (150° F.)]; (m) Air compressors having a capacity of less than one hundred ten cubic feet per minute (110 ft.3/min.) at one hundred pounds per square inch (100 lbs./in.2) pressure; (n) Motor or engine driven electric generator sets used for welding or lighting not in excess of fifty kilovolt amperes (50 KVA); or (o) Low pressure steam boilers having gravity or trap returns. 400.2 The operation and maintenance of the following equipment shall be by or under the daily supervision of a steam or other operating engineer who is duly licensed in the proper class by the Board of Examiners for Steam and Other Operating Engineers in the District of Columbia: (a) Boilers and boiler auxiliaries; (b) Steam engines; (c) Refrigeration equipment with non-toxic and non-inflammable refrigerant driven by electric motors in excess of twenty-five (25) horsepower; (d) Refrigeration systems using the heat absorption cycle with non-toxic and non-inflammable refrigerant; (e) Refrigeration systems of five (5) or more compressor horsepower using a toxic or inflammable refrigerant; (f) Refrigeration systems of three (3) or more tons using the heat absorption cycle with a toxic or inflammable refrigerant; (g) Internal combustion engines in excess of twenty-five (25) horsepower; and (h) Air compressors driven by electric motors or internal combustion engines. AUTHORITY: Unless otherwise noted, the authority for this chapter is An Act to regulate steam-engineering in the District of Columbia, approved February 28, 1887, 24 Stat. 427, ch. 272. Sec. 2. SOURCE: §§1.1 and 1.2 of Commissioners' Order No. 301, 945, 5M DCRR §§1.1 and 1.2.