Subsection B8 – Exits from StoreysC

Subsection B8 – Exits from StoreysClause B8.1Every building, except those buildings permitted under Clause B6.1 to have only one required staircase, should be so constructed that there are available from each storey not less than 2 exit routes or such greater number as may be required by Table B2. The width of each exit route and the total width of all the exit routes should be not less than the width shown in Table B2 according to the occupant capacity and the number of exit routes provided. Provided that:(a) this requirement should apply to only one of the storeys of a maisonette; and(b) where two or more exit routes (required by Table B2 to serve a storey) vary in width, any width of an exit route in such group in excess of 50% above the width of the narrowest exit route in such group should not be included in the calculation for the minimum total width of exit routes as required by column 4 of Table B2.Clause B8.2Where two or more required staircases are needed, people using one required staircase should be able to gain access to at least one other required staircase at any time, without having to pass through other person’s private premises. Such access should be provided in the following manners:(a) at each floor;(b) in case of domestic building or composite building not exceeding 15 storeys in height above the lowest ground storey, at least every 5 storeys; or(c) in case of refuge floor(s) are provided evenly between floors of the building, at the refuge floor(s) and the roof.Security measures that prevent access to a required staircase must be automatically deactivated upon actuation of a fire alarm or in power failure situation.