Warning lights, sirens and vehicle colors help identify a police cars, fire trucks and ambulances. These warning devices (lights, sirens and vehicle colors) aim to cut down on response time and ambulance transport time and to make the emergency vehicle safer.
In recent years, reports document the frequency of emergency vehicles involved in accidents. The National Safety Council reported that about 18,300 police cars were involved in police-reported motor-vehicle traffic accidents. An estimated 2,400 firetrucks and 2,800 ambulances were also involved in accidents. Also, 139 police cars, 23 firetrucks and 39 ambulances were involved in fatal traffic accidents.The American Academy of Orthopaedic Surgeons has said that "the siren is probably the most overused piece of equipment on an ambulance. It does not really help other motorists in closed cars. Motorists driving at the speed limit with the windows up, and the radio and/or the air conditioner or heater set on high, cannot hear the siren until the ambulance is only a short distance away. If the radio is particularly loud, the other driver may not hear the siren at all."
At about 60 mph, the siren barely precedes the speeding ambulance, so that vehicles ahead of it cannot respond to its warning. Studies have shown the distance for getting the attention of a motorist traveling at 60 mph to be within five feet of the ambulance's bumper. A United States Department of Transportation study found that only 26 percent of the occupants of a closed car with the windows rolled up could tell from which direction the siren was coming.
Emergency dispatch experts such as Salt Lake City's Dr. Jeff Clawson have identified which emergency calls require the use of lights and siren and those that don't. A North Carolina study found that ambulances using lights and siren reached the hospital emergency department 43.5 seconds faster than the non-lights-and-siren ambulances. This study strengthens the position of the National Association of EMS Physicians and the National Association of State EMS Directors to limit the use of lights and sirens due to traffic accident risks. In some cases, ambulance lights and sirens can be dangerous and may not save a significant amount of time.
Firetrucks are predominantly painted red, but that may not be the safest color to prevent traffic crashes. A study published by the National Safety Council reported a higher accident rate (nearly 300 percent) for the traditional red and white fire truck than for vehicles painted lime-yellow in Dallas, Texas over a four-year period.
Motorists should always be vigilant about traffic around them. When an emergency vehicle enters the scene, motorists should safely move to the right side of the roadway to allow the emergency vehicle to pass. The safety record of emergency vehicles can be improved; thousands of these vehicles should not be involved in accidents each year.