Section 243(b) in U.P. Building And Other Construction Workers (Regulation Of Employment And Conditions Of Service) Rules, 2009
(b)No building worker is allowed to enter any confined space or tank or trench or excavation wherein there is given off any duct, fumes or other impurities of such nature and to such extent as is likely to be injurious or dangerous to the building worker or in which explosives, poisonous, noxious or gaseous material or other harmful articles have been carried or stored or in which dry ice has been used as a refrigerant, or which has been fumigated or in which there is a possibility of oxygen deficiency, unless all practical steps have been taken to remove such dust, fumes, or other impurities and dangers which may be present and to prevent any further ingress thereof, and such workplace or tank or trench or excavation is certified in writing by a competent person to be safe and free from dust, fumes, gas etc. for the entry of such building and other construction workers.
