I. The inspection requirements of RSA 157-A:8, 9-a, and 10 shall not apply to private residences or apartment houses of less than 3 family units.
   II. This chapter shall not apply to the following boilers:
      (a) Boilers under federal control, or United States Coast Guard control.
      (b) Manually fired boilers for model locomotive, boat, tractor, stationary engines, or antique motor vehicles constructed or maintained only as a hobby for exhibition or educational or historical purposes, not for commercial use; provided that such boilers have an inside diameter of less than 12 inches or a grate area not in excess of 2 square feet and equipped with an ASME stamped safety valve of adequate capacity and size, a water level indicator and a pressure gauge.
      (c) Boilers with less than 200,000 BTU/HR output in apartment houses.
   III. This chapter shall not apply to the following pressure vessels:
      (a) Pressure vessels under federal control, or United States Coast Guard control.
      (b) Pressure vessels used for transportation or storage of compressed gases when constructed in compliance with specification of the Interstate Commerce Commission and when charged with gas, marked, maintained, and periodically requalified for use, as required by appropriate regulations of the Interstate Commerce Commission.
      (c) Air tanks located on vehicles operating under the rules of the states' authorities and used for carrying passengers or freight.
      (d) Air tanks installed on the right of way of railroads and used directly in the operation of trains.
      (e) Pressure vessels that do not exceed (1) 5 cubic feet in volume or 250 psig, (2) 1-1/2 cubic feet in volume or an inside diameter of 6 inches, and 3,000 psig.
      (f) Pressure vessels operating at a working pressure not exceeding 15 psig.
      (g) Water-containing vessels (excluding hot water heaters) having a working pressure not to exceed 125 psig including those with air, the compression of which serves only as a cushion.
      (h) Tanks containing air and liquids in which pressure is maintained by pumps.
      (i) Group I refrigerant receivers (A.S.H.R.A.E.).
   IV. This chapter shall not apply to hot water heaters installed after the effective date of this act provided that none of the following limitations are exceeded:
      (a) Heat input of 200,000 BTU/HR.
      (b) Water temperature of 210 degrees Fahrenheit.
Source. 1967, 236:1. 1988, 31:8. 1995, 142:4, eff. July 23, 1995.