Technical Booklet E Fire Safety·Page 62
Escape Stairway Capacity Formula for Buildings More Than 10 Storeys
For buildings exceeding 10 storeys using simultaneous evacuation, escape stairway capacity must be calculated using a specific formula for stairs not less than 1100 mm wide.
(ii) in a building of more than 10 storeys – that derived from the formula –
P = 200w + 50(w – 0.3)(n – 1) for stairs not less than 1100 mm wide,
where
P = the number of people that can be accommodated;
w = the width of the escape stair (in metres); and
n = the number of storeys served by the stair.
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