Unless specifically provided otherwise in this regulation, any existing Boiler, Pressure Vessel or Refrigeration or Air Conditioning System having met the provisions of the applicable laws, codes, rules or regulations in effect at the time such Boiler, Pressure Vessel or Refrigeration or Air Conditioning System was installed, shall be allowed to continue to be operated pursuant to its designated service, provided that the Boiler, Pressure Vessel or Refrigeration or Air Conditioning System has been maintained by the owner in accordance with applicable laws, codes, rules, regulations and manufacturers' requirements.
522 CMR, § 1.09