Technical Booklet E Fire Safety·Page 38·2.8
Access rooms to habitable rooms on storeys above
Where a habitable room is an access room to a habitable room on the storey above via a stairway, the upper storey must not exceed 4.5 m above ground level, and the foot of the stairway must be within 3 m of a final exit or a door opening into a hallway.
Where a habitable room, by virtue of a stairway discharging into it, is an access room to a habitable room on the storey above –
(a) the upper storey should be not more than 4.5 m above ground level; and
(b) the foot of the stairway should be not more than 3 m from –
(i) a final exit; or
(ii) a door opening directly into a hallway (including a corridor leading to the hallway).
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