An emergency vehicle is known as police vehicles, ambulance vehicle, fire truck and security and utility vehicles. These vehicles usually have red, white, blue or a combination of these lights when patrolling for an emergency. Vehicles from police cars to fire trucks, as they rush to a destination for some emergency or are stationery at the side of road comes in the category of emergency vehicles. These vehicles need to be fitted with the correct visual warning signs and signage to warn other road users and the public in general that they are rushing to get another destination. The lighting system of these cop cars and fire trucks is similar to other occupations as well, like construction and utility vehicles.
Vehicles mounted warning lights are used in a wide range of enforcement, road crash, health and fire emergency, road maintenance and development contexts. Many researchers concluded that Fluorescent colors (especially yellow-green and orange) offer higher visibility during daylights hours.
Emergency vehicle lights serve two major functions. Firstly they identify the vehicles as police, fire, ambulance, or other emergency services such as state emergency services, council, or department of main roads to provide an informed and predictable public response. Secondly, they present a highly conspicuous form, to provide other road users with information about distance, direction, and the speed of the vehicle so that they can behave with due caution or to take appropriate action.
Generally, we see lights flashing colors on these emergency vehicles. These flashing colored LEDs are guided to the other road users through intersections, warn them of having danger, signal drivers to pull over and stop, and convey us to slow down. Police vehicles, ambulances and fire trucks all require different equipment such as flashing colored lights, or light bars with an audio warning system, grille lights to a siren and public address system with speaker and much more.
Bright lights are essential in managing traffic and keeping us all safe on the road. Implication of contrast colors can help drivers to identify a hazard amid the visual confusion of the roadway. Different colors of light notify different indications such as a flashing blue light indicates a volunteer firefighter responding to an emergency call. A flashing green light indicates that a volunteer of ambulance service member responding to an emergency call. And if we see any amber color flashing light that means a hazard vehicle engaged in a hazardous operation for example snowplow, tow truck, utility company vehicle. Some time a flashing amber light emphasize on the vehicle of an individual who is a member of civil or crime patrol.
The blue lights should ideally have same intensity as red lights on emergency to avoid confusing the police as to the direction and speed of travel of vehicle. As the human eye has differential sensitivity for lights of different colors and blue light operates within a narrow band of wavelength. If you used a clear light with blue or red filters then the light bulb under blue filter would have to seven times stronger than the one under red filter.
The overall objective of police, fire truck, ambulance, and other emergency services revolves around public safety. Emergency lighting promotes these objectives in two ways:
Identification: to clearly identify the vehicle as belonging to police, ambulance, fire or other emergency services so that the relevant response can be made by the public and safety protected.
Conspicuity: to present a highly visible form that allows identification at a distance sufficient for road users or pedestrians to take appropriate action. This may be facilitating uninterrupted, speedy path for the emergency vehicle, or it may be avoiding the parked emergency vehicle and being alert to possible hazards, traffic operations or random.
These lighting systems in emergency vehicles also plays important role in occupational health and safety considerations for emergency service personnel.
- It is important that the best use is made of available lighting technology to facilitate identification and conspicuity.
- Correct policy and procedures should be in implemented to facilitate the safe use of emergency lights and sirens to minimize accidents involving emergency vehicles.
Research on the best type and best use of, emergency lights has become largely out-dated as lighting technology, along with societal changes in transport, has progressed at a rate which has outstripped research into this area.
Emergency Service vehicles have amber lighting on vehicles. Confusion in identification of emergency vehicles by the public due to changes in vehicle lighting (i.e. moving all emergency vehicles to red/blue) has not been identified as an issue. However, ambulance and fire personnel becoming subject to attack due to miss-identification as police have been reported, but changes to uniform appear to have reduced this problem. There are no significant reports of more attacks on emergency service personnel due to changes in lighting on vehicles.
From the public point of view, driver reactions should be similar regardless of whether the vehicle belongs to police, fire or ambulance services. If an emergency vehicle approaches from the rear, drivers are required to pull over to allow the vehicle to pass. And if the vehicle does not pass, they should stop. If the emergency vehicle is ahead, the appropriate reaction is to slow down and be prepared to stop.
It is essential that emergency vehicles be higgledy visible from all angles to a distance of at least 200 meters (Vehicle Standards, Driver, and Vehicle Policy Branch). In practice, visibility can vary, as depending on the nature of the emergency, vehicles may be parked with headlights at the emergency site, parked as a blockade, be moving at high speed, or operating within a variety of weather conditions or backgrounds. Lighting must also facilitate the safe movement of emergency workers around accidents/traffic hazards.