Technical Booklet E Fire Safety·Page 63·Worked examples (b)
Worked Example: Stair Width Calculation for 12-Storey Office Building with Uneven Population Distribution - Lower Floors
Demonstrates stair width calculation for lower floors (1-9) in a 12-storey office building where 1000 people occupy floors 1-9 and 200 occupy floors 10-11, using protected lobby entry with both stairs available.
The population is not distributed evenly (e.g. 1000 people occupy floors 1 to 9, and 200 occupy floors 10 to 11). As the top office storey is at a height greater than 18 m, both stairs need added protection (see paragraph 2.69). If both stairs are entered at each level via a protected lobby, then both stairs can be assumed to be available (see paragraph 2.64).
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