Section 74(c) in The Punjab Capital (Development and Regulation) Building Rules, 1952
(c)Increase by 2.5 cms for every additional 15 persons until a maximum of 9, is reached. A single staircase of the width mentioned in (c) above may be replaced by two staircase each of width of atleast 6 feet.(ii)The staircase in these buildings shall be of fire-proof materials. Notwithstanding the above, staircases in private portions of public buildings/commercial buildings or warehouse and industrial buildings, not open to general public may be of the sizes mentioned for the residential buildings, for more than two families and commercial buildings.(iii)The minimum treat shall be 28 cms. and maximum rise 18 cms. All staircases and walls enclosing the staircase in public building, warehouse and industrial buildings shall be of fire-proof materials.(iv)The stair data for the buildings governed by Architectural Control shall be in accordance with the stair data as shown in the Architectural Control or as per Clauses (i), (ii) and (iii) above.]
