(1)

Except as provided in Sentence (2) and Article 9.8.4.6., where a flight of stairs consists of both tapered treads and rectangular treads, all the treads shall have a uniform run when measured at a point 300 mm from the centre line of the inside handrail.

(2)

Where tapered treads are located at the bottom of a mixed-tread flight, the run of the tapered treads when measured at a point 300 mm from the centre line of the inside handrail is permitted to exceed the run of the rectangular treads.