R 408.42123 Definitions; S, T.

Rule 2123. (1) "Spiral stairway" means a series of steps attached to a vertical pole and progressing upward in a winding fashion within a cylindrical space. (2) "Stair platform" means a landing that breaks a continuous run of stairs. (3) "Stair railing" means a vertical barrier that is erected on an exposed side of a stairway to prevent employees from falling to lower levels. The top surface of a stair rail system may also be a handrail. (4) "Tread depth" means the horizontal distance from the front to the back of a tread, excluding nosing, if any.