- Emergency vehicle equipment
Emergency vehicle equipment is the equipment fitted to, or carried by, an emergency vehicle, which is additional to any equipment such as
headlights, steering wheels or windshield/windscreens that a standard non-emergency vehicle is fitted with.
Visual warning devices
Emergency vehicles are highly likely to be involved in hazardous situations, including relatively common incidents such as a road traffic collision. They are also required to gain access to incidents as quickly as possible, and in many countries, are given dispensation from obeying certain traffic laws; for instance, they may be able to treat a red traffic light or stop sign as a 'give way', or be permitted to break the speed limit.
For these reasons, emergency vehicles in many countries worldwide, are fitted with visual warnings to alert members of the public (and in particular, other motorists and road users), either as they approach the vehicle, or it approaches them. Visual warnings can be of two types - passive or active
Passive visual warnings
'), chevrons (arrowheads - often pointed towards the front of the vehicle if on the side, or pointing vertically upwards on the rear) or stripes (along the side - these were the first type or retro-reflective device introduced, as the original 3M reflective material only came in tape form). In some countries, in addition to retro-reflective markings, the vehicles are now painted in a bright yellow or orange colour underneath, in order to maximise visual impact.
Another passive marking form is the name of the emergency service spelled out in reverse on the front of the vehicle (e.g. Ambulance or Fire). This enables drivers of other vehicles to more easily identify an approaching emergency vehicle in their rear view mirrors. The vehicle may also display the name of their owner or operator, and a telephone number which may be used to summon the vehicle.
Ambulances may also carry an emblem (either as part of the passive warning markings or not). Some ambulances may display a Red Cross, Red Crescent or Red Diamond (collective known as the Protective Symbols). These are symbols laid down by the
Geneva Conventions, and all countries signatory to it agree to restrict their use to either (1) Military Ambulances or (2) the national Red Cross or Red Crescent society. Use by any other person, organisation or agency is in breach of international law. The protective symbols are designed to indicate to all people (especially combatants in the case of war) that the vehicle is neutral and is not to be fired upon (see Military ambulances), hence giving protection to the medics and their casualties, although this has not always been adhered to.
Many ambulances use the
Star of Life, which indicates that the vehicle's operators can render their given level of care represented on the six pointed star.
Active visual warnings
The active visual warnings are usually in the form of flashing coloured lights (also known as 'beacons' or 'lightbars'). These flash in order to attract the attention of other road users as the emergency vehicle approaches, or to provide warning to motorists approaching a stopped vehicle in a dangerous position on the road (and if the emergency vehicle positions itself to deliberately move people away from an incident, this is called fend off). Common colours for emergency vehicle warning beacons are blue and red, and this varies by country (and sometimes by operator).
The lights can be made to flash via a range of techniques, dependent on the technology used, and the desired end effect. Types of beacon include:
Light bars - A long but narrow 'strip' of lights on top of an emergency vehicle, which can be configured with almost infinite combinations of different lighting technologies from the list below. These are typically the main source of flashing light for the vehicle, and are used on overt marked emergency vehicles. They can also be divided in to sections, with an array of functions (for instance front blue flashing lights, and rear red flashing lights, switched separately). Due to the nature of the wind resistanceencountered by these large units, the majority must be fixed to the car permanently, although some units (usually smaller) are available with either magneticor suction cupmountings which can be removed. The Light bar may also contain the Audible Warning devices
* Beacons - A simple lighting device, often found on smaller emergency vehicles, or unmarked cars, (where it is removable) and consists of a clear or transparent coloured casing surrounding a lamp and a revolving mirror. Some beacons consist of one or several lamps that revolve, instead of using a mirror. These were the original type of emergency vehicle lighting
* Alternating Vehicle Lights or Wig-wags - This causes the
Full beam headlights, or Fog lightsto flash in a pattern (usually alternating left-right-left, although it can be together, or in a random pattern), and can also be used at the rear of the vehicle on Brake, Fog or reversing lights to warn vehicles approaching from the rear.
* Grille lights - Flashing lights fitted on, in to or behind the grille of the emergency vehicle, creating forward facing flashing effects, designed to be seen in the rear view mirror of moving traffic in front of the vehicle. These can be fitted to both overt and covert emergency vehicles, by simply changing whether they are mounted internally or externally, or by varying the lens colour (so that they may look like
fog lightson a covert vehicle
* Dash Lights - These are forward facing lights, like grille lights, but mounted on the dashboard of the emergency vehicle. They are more often found on covert vehicles, but may be found on some marked vehicles which are trying to increase visibility. In order to avoid dazzling the driver, they are normally fitted with 'shields' around the light which stop the light reflecting in to the cab.
* Deck lights (or Parcel Shelf lights) - Rear facing equivalents of the Dash Lights which are placed on the Parcel Shelf of the vehicle. These can be used in both overt and covert vehicles.
* Directional Warning Arrows or arrow sticks - A strip of lights (typically amber or yellow) which light up in sequence to direct traffic to the right, left, or around both sides of an emergency vehicle. They may be found mounted on the back of a lightbar, on a car's package shelf (shining out the rear window) or on some other conspicuous location on the rear of a vehicle.
* Information Matrix Signs - These special active visual warnings are used to convey words to vehicles approaching from behind the emergency vehicle and often carry messages such as "Police. Stop" or other relevant message. Some systems allow only preprogrammed messages, where others can be fully customised.
Many governments list specific requirements for emergency vehicle lighting. These requirements may address the colour, location and intensity/visibility of the lights, and whether they should flash or burn steadily. Laws also may regulate what vehicles may display these lights, and under what circumstances they may do so.
Technically, the warning lights may be of several types, which includes:
Incandescent- These are 'traditional' light bulbs, and may be found in the 'beacon' type lights, and will also be found where the vehicles own lighting is used (such as wig-wag). They may be of several types, including Halogen or Xenon. They may rely on an extra piece of equipment (such as a rotating mirror) to make them flash, or are simply turned on and off.
Strobe lights - These lights give a short flash, which is usually very bright over a longer range than an incandescent light. They are usually made to work in multiples (such as three rapid flashes consecutively) and are often used in patterns between sets, which increases their effectiveness.
LEDLights - These are more recent developments, using the 'Super Bright' LED technology, and are entering wide use as they are easy to fit (being only a few millimetres wide, rather than several centimetres for most strobes and incandescent lights). This makes them particularly suitable for covert use.
Audible warning devices (sirens)
When an emergency vehicle is responding, it often uses audio warning devices in addition to the visual warnings provided by its warning lights. Audio warning devices are turned off once the vehicle is on-scene. Such devices include:
* Sirens - These can be fully electronic,
electric, or manual, but are all designed to create changing sound patterns. These patterns vary by model of siren. Emergency drivers are often trained to use different siren tones in different conditions, to achieve maximum effectiveness through traffic. A long standing problem for emergency services has been traffic being unable to determine the direction a siren is approaching from, and different tones have been developed on some electronic sirens to help combat this, such as the use of white or pink noisein between more conventional siren noises, which helps people to pinpoint their origin.
Public addresssystem - Sometimes linked to the electronic or electric siren, or possibly stand alone, this system allows the voice of the operator to be amplified to give direction. This is found especially useful in heavy pedestrian traffic.
Air horn- These devices simply force air through a shaped pipe to create noise. They can be used to create the classic two tone 'nee naw' sound which led to the colloquial expression for lights and sirens on emergency vehicles of blues and twos. They can be both mechanical and electronic.
* Bells - Usually found on older or classic emergency vehicles, these were the original methods of notifying people of the approach of emergency vehicles. They were first hand bells, and later replaced by electric versions.
whistles - These are no longer used, but still referred to in some legislation, and may be found on classic emergency vehicles, an exhaust whistle is fitted to a vehicle's exhaust pipe, and functions similar to a steam whistle, with the exhaust gasses replacing the steam.
Some emergency vehicles may not be allowed to use their sirens on side streets and are only able to use their lights, and at intersections they toggle their sirens on and off to give warning. They can only use the sirens fully when they turn onto a main road. Some countries also have restrictions on the times of day in which audible warnings can be used.
Auxiliary lighting is light used for illumination, to supplement factory-installed headlights or to illuminate areas to the side of or behind the vehicle. It is typically white or near-white light. Some emergency scenes require additional lighting if the emergency workers are to be able to effectively deal with the emergency. Also, building numbers are often obscured by darkness, making it difficult for emergency workers to find the scene of an emergency. For these reasons, emergency vehicles are often equipped with auxiliary lighting, such as:
* spot-lights, which may be mounted on the side, top, or rear of a larger vehicle, or on the A-post/A-pillar of smaller vehicles.
flood lights, which may similarly be mounted on the side, top, or rear of a larger vehicle.
* load lights, which are used by
ambulancesand other vehicles with cargo doors to light up the area around the cargo doors.
* alley lights, which are typically found mounted on the side of a
police caror emergency vehicle's lightbar, for the purpose of illuminating areas to the side of the car, such as into an alley, or a scene at the side of the road.
* take-downs, which are typically mounted on the front of an
emergency vehicle's lightbar. Take-downs are used on police cars to illuminate the interior of a vehicle immediately in front of the police car, such as a vehicle that has been pulled over after committing a traffic violationor while conducting a high-risk vehicle stop (also called a felony stop). The bright lights also serve to blind the vision of suspects looking back toward the police. take-downs are also used on ambulances and other vehicles to illuminate a work area in front of the vehicle, such as a patient in the roadway, an accident scene, or a fire scene.
Efficient emergency responses require that emergency responders can communicate with a
dispatcher, with each other, and often with other facilities (such as hospitalsor public utilities). Emergency vehicles are equipped with the following types of equipment to do so:
two-way radio, usually operating on dedicated frequencies and channels designated for emergency use, or in some cases simply a CB radio.
* portable two-way radios, which transmit and receive on the same frequencies as the built in two-way radios, but are less powerful. Emergency workers can take these radios with them when they exit the vehicle. There are also systems (frequently referred to as mobile extenders or mobile releaters) that allow the portable radios to be relayed through the vehicles more powerful two way radio. Some emergency services
encrypttheir radio transmissions.
car phones or portable cellular phones.
mobile data terminals, or MDTs, which are computersthat communicate with the dispatcher's computer.
Laptopcomputers with Wi-Ficonnections, usually with a mounting point or docking stationwithin the vehicle. [cite web|url=http://www.publicsafetysource.com|title=Laptops for Emergency Services] These can be used as an alternative to MDTs.
PAor bullhornto communicate with other workers, or with members of the public. Most electronic sirens are equipped with a PA.
Different services require different types of equipment at emergency scenes (ambulances and fire trucks carry different types of equipment), and within one service, different units may require different equipment (
SWATtrucks carry different equipment than K-9police units do, though they are both part of the police service.) For more information, click on the type of unit that interests you: (in different locations, the same vehicle may have different names, and the same name may apply to different units; you may have to look around a bit before you find what you want.)
Air Ambulance Fire department
Fire chief's vehicle
* Engine/pumper truck
* Ladder truck/ladder/tower (Equipment found on snorkel trucks is also found here.)
* Heavy Rescue, sometimes just called "rescue". Some departments use "rescue" for
Hazardous materials response vehicle, which may be combined with the bomb squadvehicle.
* Squad truck typically used to carry first responders to a medical emergency.
Blues and twos
* [http://www.theiacp.org/documents/pdfs/LESS/ACF29B.pdf paper discussing safety equipment on police cars, specifically addressing equipment to address a series of Ford Crown Victorias that suffered rear-end-collisions resulting in fires, and addressing the use of flashing lights, reflectors, &c on police vehicles] (PDF file)
* [http://www.theiacp.org/div_sec_com/Committees/Less/FHPevaluation.pdf Florida Highway Patrol Lighting and Siren Evaluation]
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