2.1.3 Floor Over Hoistways
(a) where a machine room or control room is located above the hoistway
(b) below overhead sheaves and other equipment located over the hoistway, where means of access conforming to 126.96.36.199.3 are not provided
(a) If of bar-type grating, the openings between bars shall reject a ball 20 mm (0.8 in.) in diameter.
(b) If of perforated sheet metal or of fabricated openwork construction, the openings shall reject a ball 25 mm (1 in.) in diameter.