N.Y. Mult. Dwell. Law § 84
On or before January first, nineteen hundred sixty-nine, the department shall formulate, adopt, promulgate and thereafter from time to time amend standards of sound retardation for the walls, partitions and floors and ceilings between apartments and between apartments and public spaces situated therein based on the direct measurement of sound transmission loss determined in decibels for various frequencies or in accordance with the ASTM sound transmission class system or in accordance with such other recognized method or system for measuring reduction of sound transmission as the department may determine to be appropriate. Any construction of a multiple dwelling commenced after January first, nineteen hundred seventy shall comply with the standards promulgated pursuant to this section in effect at the time of commencement of such construction.
N.Y. Mult. Dwell. Law § 84