45.1.1 All the building types that has more than one floor, and whose floor area below 450 square meter or 1400 square meter for the total floor area, shall provide a minimum of one main staircase. Regarding every additional area, from 450 to 950 square meters per floor or from 1400 to 2800 square meter per floor, an additional staircase shall be provided.
45.1.2 The clear width of the stair landing shall not be less than the clear width of the stair, and shall not be less than 1.10 meter for the residential and office buildings, and 1.5 meter for the public buildings. The minimum clear vertical height from the bottom margin of the landing structure to the pedestrian passageway shall be 2.4 meter.
45.1.3 The maximum number of steps in one single staircase or in one direction shall be less 14 steps. All the steps shall be identical in height and width.
45.1.4 Normal staircase is 2R+T = 0.6m, R= riser and T= tread,
1. maximum R shall be 0.19 meter
2. minimum T shall be 0.25 meter
45.1.5 The minimum door inward swinging clearance shall be 0.9 meter from first step.
45.1.6 Head room over ...