(a) Automatic sprinkler protection complying with the construction provisions of article four of subchapter seventeen shall be provided as required for occupancy group B-1 or B-2 respectively, except that in existing buildings lawfully occupied as garages prior to December sixth, nineteen hundred sixty-eight, storage of forty-five thousand gallons or less of product having a flash point over one hundred degrees° F (tag open cup) in the cargo space of tank truck or other vehicles approved for such storage by the fire commissioner, pending delivery, shall not be deemed to require sprinkler protection.
(b) Smoke detection or thermostatic alarm with central office connection. A thermostatic alarm system or smoke detection system equipped with a central office connection complying with subchapter seventeen of this code, and reference standard RS-17-3 of the appendix to this code may be provided in lieu of the sprinkler system required under the preceding subdivision in existing buildings lawfully occupied as garages prior to December sixth, nineteen hundred sixty-eight, when the storage of fuel oils or other products having a flash point over one hundred degrees F (tag open cup) is twenty-two thousand five hundred gallons or more but not exceeding forty-five thousand gallons in the cargo space of tank trucks or other vehicles approved for such storage by the fire commissioner, pending delivery.
(c) Portable fire fighting appliances, as the fire commissioner may direct, shall be provided in existing buildings lawfully occupied as garages prior to December sixth, nineteen hundred sixty-eight, when the storage of fuel oils or other products, having a flash point over one hundred degrees F (tag open cup), in the cargo space of tank trucks or other vehicles approved for such storage by the fire commissioner, pending delivery, is less than twenty-two thousand five hundred gallons.