Section 33(b) in The Assam Cinemas (Regulation) Rules, 1960
(b)All staircases shall be constructed entirely of bricks, stone, cement or concrete with fire-resisting roof and ceiling and shall have solid square (as distinguished from span drill) steps and landings of approval stone or of such other fire-resisting material and construction as may be approved by the Licensing Authority with treads not less than 11 inches wide and with risers of not more than 6 inches high (each lapping at least one inch over the back edge of the steps below it) in flights of not more than 15 or less than 3 steps.
