Technical Booklet E Fire Safety·Page 67·2.70
Exits from protected stairways
Protected stairways must discharge directly to a final exit or through a protected exit passageway to a final exit, with lobbied doors where applicable. Escape routes serving ground and basement storeys must have increased width.
Every protected stairway should discharge either –
(a) directly to a final exit; or
(b) to a protected exit passageway leading only to a final exit. Where the stairway is lobbied, any door openings in the walls enclosing the protected exit passageway should be similarly lobbied.
Where the escape route from an escape stairway also forms the escape route from the ground and/or basement storey its width should be increased accordingly.
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