Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 29·3.23
Tapered treads going relative to straight flight
Where a staircase mixes straight and tapered treads, the tapered treads must have a going at least equal to the going of the straight flight treads.
Where a stair consists of straight and tapered treads, the going of the tapered treads should be not less than the going of the treads on the straight flight.
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