United States
A security officer’s personal vehicle from the state of Georgia (who worked in Tennessee), with a green lightbar on its roof and spotlight on the driver’s door.
In the United States, colors are generally regulated at the state and local levels, but there are some commonalities.
Red almost always denotes an emergency vehicle if the lights are facing forward. In the state of Iowa, red lights can also be used on a funeral hearse, but only during funerals. In Washington State, red lights are also used on tow trucks, but only if the vehicle is not in motion. In Wisconsin, tow trucks are required to be equipped with red lights but such lights may be operated only when the tow truck is standing on or near the traveled portion of a highway preparatory to towing or servicing a disabled vehicle. A near universal exception to this rule is school buses which are allowed to use rear and forward facing, usually alternatively phased flashing red lights just before, during, and after passenger loading & unloading as a signal for all other traffic to stop.
Amber or Yellow lights are often used by vehicles such as construction vehicles, tow trucks, snow plows, funeral escorts and hearses, security patrol vehicles or other vehicles which may be stopped or moving slower than the flow of traffic. Amber is usually the most permissively regulated color.
White is often used as an optional color on lightbars, though it may be restricted to emergency vehicles in some states. It is rarely used as the only color on a lightbar, though some states[Note 1] require flashing white beacons on school buses. Certain railroad-related machines, like fueling tankers or switching engines, may also use a flashing white light. Certain government vehicles, such as rural mail delivery vehicles, use a flashing white beacon in some states.
Green on a fire chief’s car or a mobile command post denotes the command vehicle on scene; this usage derives from the use of green flags in the Incident Command System. Green can also denote a firefighter or EMT’s vehicle in some states. In some states, green is used by private security guards. In the Commonwealth of Puerto Rico, Green is used along with Blue by Municipal Police Forces. In some states, green denotes a funeral vehicle or police escorting a funeral procession.
Blue is reserved for law enforcement, firefighters and EMTs. In New Mexico and Texas, tow trucks may have blue lights in combination with amber. In Texas, light construction and utility vehicles commonly use blue in combination with amber, though technically illegal. Alaska, Arizona, Colorado, Minnesota, and Nebraska also use blue lights on snowplows.[46][47][48]
Purple is permitted in some states to denote a funeral vehicle.[49][50][51][52]
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Police
Police agencies may use red, blue, or both, depending on the state, along with white and amber as optional colors; although amber is usually restricted to face behind the vehicle. Some police cars have an amber traffic-control stick, or “arrow stick”, behind the lightbar to direct traffic left or right around the vehicle; these usually have 6 or 8 rear-facing lights that flash in sequence.
Some privately operated special police are allowed to display the same colors as regular police, generally, if they receive their special police authority at the state level. This can include railroad, university, hospital, and humane society police departments.[53]
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Fire and EMS
Fire truck with emergency light and siren mounted on top
Fire and emergency medical services generally use red and white lights. Vehicles operated by fire departments, such as fire engines and heavy rescue vehicles, prominently use red, a color with strong cultural associations with the fire service, along with some white. Amber, and blue in some states, are also shown towards the rear, and some communities even have lighting on fire trucks not dissimilar to police (Red and Blue). Many fire chiefs’ cars have, in addition to the red lights, a single green beacon to indicate command post status. On the other hand, in Chicago and some nearby communities, fire vehicles show a green light on the right, or starboard, side of the vehicle, reflecting nautical tradition.[54]
Emergency medical vehicles, such as ambulances and paramedic fly-cars, generally use white and red, with an amber light facing the rear. Some states have a specific rule authorizing light colors for EMS vehicles, while on the other hand some EMS vehicles “inherit” their light colors from the fire or police department they are operated by or contracted to, and may show blue lights.
The National Fire Protection Association publishes the NFPA-1901 standards for fire vehicles,[55] which specifies the degree of lighting on various parts of the vehicles, with some flexibility as to color. There is also a GSA procurement specification for ambulances known as KKK-A-1822-F,[56] which many local authorities follow.
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Volunteer Personnel
Many U.S. states allow volunteer fire and EMS personnel to place emergency warning lights in their personal vehicles for use when responding to emergencies. The laws vary greatly by state. For instance, Virginia state law allows emergency personnel to equip one private vehicle “with no more than two flashing or steady-burning red or red and white combination warning lights”.[57]
The degree of lighting is mandated by law and also by local custom in most areas, and can vary from a single rotating light on the dashboard or roof, to a setup much like modern police cruisers. Some states also allow volunteer use of sirens and air horns to request the right of way.
A New Jersey EMT’s vehicle at night with lights flashing
In some states, volunteers are allowed to use the normal red lights, while in other states volunteers must use some other color, usually blue or green. In the latter case, the lights are used as a courtesy to “request” the right of way and generally do not mandate pulling over. Some states, such as Pennsylvania, limit volunteer use of red lights to chiefs and captains of squads.
Separate colors may be used for fire versus EMS volunteers. In Connecticut, Indiana, and New York, volunteer firefighters use blue while volunteer EMTs use green. In New Jersey, volunteer fire and ambulance personnel use blue lights in their personal vehicles while responding to their stations. In NJ red lights are only allowed for emergency vehicles, fire chiefs or other law enforcement vehicles. New York also certifies some volunteer EMTs to use red lights and sirens provided their vehicles carry certain equipment;[58] this is often used by Hatzolah volunteers in the NYC area. Typically in New York state, volunteer firemen use blue lights in their personal vehicles and volunteer EMS use green lights. This may generate confusion, as green lights are also used to signify an incident command vehicle.
The conflicting color assignments can create issues for volunteers who drive their vehicles out of state. While some authorities may be satisfied with covering the lights with an “Out Of Service” tarp, compliance may be more difficult in other jurisdictions. For example, Arkansas bars civilian possession of blue lights on or in a vehicle unless sealed in the manufacturer’s original package.[59]
The confusion generated by the different colors in each state can also cause problems for drivers who travel into others states. One color in their state may mean firefighter or EMT when in another state it may mean police, obviously causing problems.
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Utility Vehicles
Private Security Car with Amber/Yellow Lightbar on top.
Yellow lights are often used on vehicle involved in non-emergency work. Most utility companies, towing services, and certain types of construction equipment mount some type of lightbar or lighting system for a higher degree of visibility. In Detroit, Michigan, Angels’ Night volunteers will patrol neighborhoods with yellow lights to help deter vandalism during Devil’s Night and Halloween. Typically these lights are the single beacon kind, although lightbars have been used for vehicles of this type, especially on wreckers/tow trucks. Also in Michigan, emergency road service vehicles (tow trucks, wreckers, etc.) are allowed to use red warning lights only when stationary.
In states that do not enforce specific rules about green, yellow or white lights, they are often used by entities like private security companies which may be ineligible to use blue or red lights but wish to distinguish themselves from utility vehicles. Security vehicles generally use their lights on private property and are generally not allowed a “courtesy” or “emergency” light on public roads.
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Optional colors
Often, while certain colors are customarily used by different services, there are other colors that are optionally used, such as amber and white. Sometimes, this is done to satisfy particular regulations; for example, California requires a steady red light facing forward and a flashing amber light to the rear on every emergency vehicle
minneapolis bike lights 