SWS – Safety Warning System and SA – Safety Alert are alerts for emergency vehicles that transmit these safety signals. These signals transmit on K band. Rocky Mountain Radar models detect all safety warning radar signals, including SWS & SA. We do not decode their information, because we believe that the driver should not be confused with extra information. Not all emergency vehicles are equipped with a Safety Warning or Safety Alert transmitter. This equipment is very expensive, most police and fire departments do not have extra resources to afford this type of equipment.