The Radio Association Defending Airwave Rights Inc. conceived and developed the concept of the Safety Warning System (SWS). This system consists of a transmitter and receiver (detector). MPH Industries Inc manufactures SWS transmitters.
The SWS holds promise as a means of warning drivers of upcoming hazardous conditions. However, its effectiveness is based directly upon the percentage of vehicles that are equipped with regular or enhanced SWS radar detectors. Therefore, until the number of radar detector users increases, the system is not likely to have a significant impact on the speed reductions at work zones.