Section 77(xvii) in Assam Notified Urban Areas (Other than Guwahati) Building Rules, 2014
(xvii)no staircase shall have a flight of more than 15 steps or less than 3 steps and width of the landing between such flight shall be the same width of the staircase. The tread of the step shall not be less than 250 mm and rise not more than 150 mm;
