(1) Step frame shall bemade ofincombustible material. Step treads shall be horizontal and made ofincombustible material and shall afford a secure foothold.
(2) If the landing is ofconcrete, it shall have edge insertions ofmetal, wood or other anti slip material.
(3) The depth ofany step tread in the direction oftravel shall be not less than 40 centimeters and the rise between treads shall be not more than 22 centimeters. The width ofstep tread shall be not less than 40 centimeters and not more than 102 centimeters.
(4) The maximum clearance between step treads on the horizontal run shall be 4 millimeters.
(5) The tread surface ofeach step shall be slotted in a direction parallel to the travel ofthe steps. Each slot shall be not more than 6.5 millimeters wide and not less than 9.5 millimeters deep and the distance from centre of adjoining slots shall be not more than 9.5 millimeters.