Section 226(a) in The Building And Other Construction Workers '(Regulation Of Employment And Conditions Of Service) Central Rules, 1998
(a)in case five hundred or less workers are employed at such construction site there is an ambulance room at such construction site or an arrangement with a nearby hospital for providing an ambulance room and such ambulance room is in the charge of a qualified nurse and the service of such ambulance room is available for building worker employed at such construction site at every time when he is at work;