N.Y.C. Admin. Code § 27-956: § 27-956 Standard for installation of sprinklers.

(a) Except as herein provided in subdivision (b) of this section, the installation, components, sizing, spacing, location, clearances, position, and type of systems shall be in accordance with reference standard RS 17-2, except that sprinkler systems in one and two family dwellings may in the alternative be in accordance with reference standard RS 17-2B, and sprinkler systems in other residential buildings not exceeding six stories or seventy-five feet in height and in other residential spaces in buildings not exceeding six stories or seventy-five feet in height may in the alternative be in accordance with reference standard RS 17-2A.

(b) Notwithstanding any provision to the contrary contained in reference standards RS 17-2, RS 17-2A or RS 17-2B sprinklers may be omitted from clothes closets, linen closets, pantries, water closets, water closet compartments, bathrooms, general toilet rooms and shower rooms in buildings and spaces classified in occupancy group J-2 and J-3.