4.9.3 Nosings.
The undersides of nosings shall not be abrupt. The radius of curvature at the leading edge of the tread shall be no greater than 1/2 in (13 mm). Risers shall be sloped or the underside of the nosing shall have an angle not less than 60 degrees from the horizontal. Nosings shall project no more than 1‒1/2 in (38 mm) (see Fig. 18).
User Comments/Questions
Add Comment/Question