A device, system and method for controlling quality of service of communication devices based on a predicted hazard path is provided. From an initial location of a hazard in a building and an electronic representation of the building, a predicted hazard path through the building is determined, as well as geofences, each associated with a respective weight. Geofences that include the predicted hazard path have a higher weight than geofences that exclude the predicted hazard path. Respective network quality of service for communication devices is controlled based on their locations in the building, relative to the geofences, such that a first communication device located in a first geofence that includes the predicted hazard path receives better network quality of service than a second communication device located in a second geofence that excludes the predicted hazard path, the second geofence having a lower weight than the first geofence.