A service management system facilitates and validates service on building management systems installed in a building with an access control system. A service workflow module receives device events from control panels of the building management systems and combines them with local service data from mobile computing devices of technicians performing the service, generating service events. A validation module receives the service events and retrieves access control events from an access control system controller of the access control system and determines whether they are coherent. The service workflow module also infers the location of the technician based on the access control events and sends service eligible devices to be displayed on the mobile computing devices of the technicians. In an alternative embodiment, device events from a building automation system such as a heating, ventilation and air-conditioning system are further used to validate the service events.