Section 166(b) in The Building And Other Construction Workers '(Regulation Of Employment And Conditions Of Service) Central Rules, 1998
(b)(i)doors of man-locks at an excavation or tunnelling work are made of steel;(ii)man-locks used at a tunnelling work are airtight and devices are provided for sealing the doors when such locks are under pressure;(iii)the anchorage of a man-lock used at tunnelling work have adequate strength to withstand the pressure exerted by air on the man-lock;(iv)there is adequate room available for the building worker for working in the man-lock used at tunnelling work;(v)where work is carried out in any compressed air tunnel, a man-lock in accordance with the relevant national standards is used for such tunnel;
