Technical Booklet R Access to and Use of Buildings·Page 29·4.9
Protection under stairs and ramps
Areas below stairs or ramps with headroom less than 2100 mm above circulation routes must be protected by a distinguishable barrier rail with a continuous vertical barrier or floor-level kerb.
Any area below the soffit of a stair or a ramp and its landings that is less than 2100 mm above a circulation route, should be protected by a distinguishable barrier rail which incorporates either a vertically continuous barrier or a kerb at floor level. See Diagram 2.2. The provisions of this paragraph should not apply to the headroom above a flight or ramp and landings.
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