Technical Booklet E Fire Safety·Page 61·Table 2.5
Table 2.5: Minimum width of escape stairs
Specifies the minimum stair width required based on the building purpose group, use type, and number of people the stair serves. Width requirements range from 800 mm for small stairs to 1100 mm or wider depending on occupancy.
Table 2.5 Minimum width of escape stairs
Situation of stair | Maximum number of people served(1) | Minimum stair width (mm)
1. In a Purpose Group 2(a) building (unless it will only be used by staff) | 150 | 1000
2. In a Purpose Group 5 building and serving an area used for assembly purposes (unless the area is less than 100 m2) | 220 | 1100
3. In a building of any other purpose group and serving an area with an occupancy of more than 50 | Over 220 | Note (2)
4. Any stair not described above | 50 | 800
Notes:
(1) Assessed as likely to use the stair in a fire emergency.
(2) See Table 2.6 for sizing stairs for simultaneous evacuation and Table 2.7 for phased evacuation.
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