Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 31·3.32
Width of stair flights
Stair flights must have a minimum surface width of 1200 mm, with handrails protruding no more than 110 mm into this width. Flights wider than 1800 mm must be divided into separate flights.
A flight should have a surface width of not less than 1200 mm. Where a handrail protrudes into the surface width of a flight by more than 100 mm, the surface width should be increased accordingly. In any case, the maximum protrusion of a handrail into the surface width of a flight should be 110 mm. A flight of steps which has a surface width wider than 1800 mm, should be divided into flights which are not wider than 1800 mm. The minimum surface width of 1200 mm then applies to each flight.
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