Minimum stair width for phased evacuation

The minimum width of a stair for phased evacuation should be that given in Table 2.7 for the appropriate maximum number of people on the most heavily occupied storey. Table 2.7 Minimum width of escape stairs for phased evacuation Maximum number of people in any storey(1) | Stair width(2) (mm) 100 | 1000 120 | 1100 130 | 1200 140 | 1300 150 | 1400 160 | 1500 170 | 1600 180 | 1700 190 | 1800 Notes: (1) 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. (2) Where the stair serves a storey more than 30 m above ground level the width should not exceed 1400 mm [see paragraph 2.63(d)].