Technical Booklet E Fire Safety·Page 65·Table 2.7 Note (1)
Phased evacuation stair width calculation for populations over 190
For buildings with more than 190 people on the most heavily occupied storey, stair width must be calculated using the formula W = (P × 10) − 100 mm.
Where the number of people (P) on the most heavily occupied storey is more than 190, the minimum width of the escape stair (W mm) should be calculated from W = (P x 10) – 100.
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