(a) Elevators. In existing buildings classified in occupancy group J-1, at every floor above the main entrance floor, all passenger elevators shall open only into elevator vestibules, except for:
(1) Such existing buildings which contain spaces classified in occupancy group C or F and have an automatic sprinkler system protecting all spaces (except boiler rooms) not in occupancy group J-1 and all exits and corridors serving such spaces located on or below the lowest floor containing sleeping rooms as well as all storage closets no matter where located, except that storage closets less than seventy-five square feet may, in the alternative, be provided with smoke detectors which shall be of the central supervisory type connected to an approved central station; or
(2) Such existing buildings which contain no spaces in occupancy group C or F, and have either:
a. An automatic sprinkler system protecting all public areas and storage closets; or
b. An automatic sprinkler system protecting all sleeping rooms and storage closets.
c. Notwithstanding subparagraphs a and b of this paragraph, storage closets less than seventy-five square feet may be provided with smoke detectors of the central supervisory type connected to an approved central station.
d. Notwithstanding any other provision of this code, the sprinklers serving the storage closets may be connected with the domestic water supply.
(b) Escalators. In buildings and existing buildings classified in occupancy group J-1, fire protection for escalators shall be provided by any one of the following methods:
(2) Automatic rolling shutters in accordance with reference standard RS 18-1; or
(3) Kiosks in accordance with reference standard RS 18-1; or
(4) Where the building section is fully protected by a supervised automatic sprinkler system and the escalator sprinklers are spaced to protect exposed sides of the escalator opening, a noncombustible heat apron constructed to bank heat around the sprinkler heads adjacent to the opening where the bottom edge of the draft curtain is not less than twelve inches below the bottoms of sprinkler heads when heads are in operation, and in no event less than twenty-four inches below the ceiling; or
(5) Spray nozzles in accordance with reference standard RS 18-1.
(c) The requirements of this subdivision shall be complied with on or before April first, nineteen hundred eighty-seven.