N.Y. Comp. Codes R. & Regs. tit. 12, § 8-2.21 – All installations.

(a) At the top of hoistways immediately below the machine or sheaves or at the machine beams, a flooring of iron, steel, concrete or wood capable of sustaining a concentrated load of 300 pounds, shall be provided.
Exceptions:
(1) The floor or guard need not extend under the hand rope pull wheel. (2) Hoistway protected at each floor by automatic trap doors. (3) Sidewalk elevators outside of building line. (4) Dumbwaiters.
(b) If metal grating is used, the spacing between members shall not exceed one and one- quarter inches.
(c) If grating members are laid flat, they shall be supported by battens spaced not more than 48 inches apart.
(d) If grating members are placed on edge, thimbles strung on metal rods running through the members shall be provided; the rods shall be riveted at the ends and spaced not more than 48 inches apart.
(e) The grating or flooring may fill the entire hoistway, otherwise the same shall extend not less than 24 inches beyond the general contour of the sheaves or machine and to the entrance to the hoistway at or above the level of the flooring.
(f) When the grating or flooring does not entirely cover the horizontal area of the hoistway, the open or exposed sides shall be provided with a standard railing, as specified in section 8-1.54, and a toeboard.
(g) Deflecting sheaves or other moving parts extending below the machine level shall be protected by cradles not greater than one-half inch mesh, not less than No. 10 gauge wire or its equivalent in strength.