A service management system facilitates and validates service on building management systems. 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. The service workflow module receives ambient radiofrequency (RF) signal data detected from the location of serviced devices. A validation module stores the ambient RF signal data and generates and a device fingerprint based on the ambient RF signal data. After device fingerprints based on the ambient RF signal data have been accumulated, the validation module determines whether current service events and ambient RF signal data are coherent with the device fingerprints and previous ambient RF signal data. The service workflow module also infers the location of the technician based on the ambient RF signal data and sends navigation information to the mobile computing device.