Section 164(7) in West Bengal Municipal (Building) Rules, 2007
(7)The service rooms shall have access by means of two passages of staircases, providing access and exit from higher and lower level floors, the width of which shall not be less than 1.2 metres and the slope shall not be steeper than one 1:1 and so located that the travel distance on any floor up to any such access or exit is not more than 15.0 metres.
