Code 3 Response

The emergency services in various countries use systems of response codes to categorize their responses to reported events. One of the best known is the Code 3 Response, which is used in several countries, particularly the United States, to describe a mode of response for an emergency vehicle responding to a call. It is commonly used to mean "use lights and siren".

In some agencies, Code 3 is also called a Hot Response. Code 1 is also called a Cold Response.

Some slang may be used, such as "Running Hot", or "Running Cold".

Some departments may use the terms "upgrade" and "downgrade" as well. If a unit is responding to a call without lights or sirens (code 1), and the unit later needs to turn on lights and sirens (code 3), the term upgrade may be used. The term downgrade may be used in the opposite situation.

Some Paramedic/EMS agencies use Priority terms:

The use of lights and sirens is up to the individual police officer driving to the call. The nature of the call is an aggravating factor when deciding when to use them. Calls are graded by either the control room direct (in the case of emergency calls) or by some sort of first contact centre (nonemergency calls). Grading is effected by such factors as the use or threat of violence at the incident being reported. Even though the grading is done by the control room, officers can request an incident be upgraded if they feel in their judgement they are needed immediately. They can also request to downgrade an incident if they feel they cannot justify using emergency equipment like blue lights and sirens.

There is no nationally agreed call grading system with a number of different systems being used across the UK and attendance times given the grade varies between forces, depending on how rural the county is. For example, Suffolk Constabulary break down Grade A emergencies into further sub-categories of Grade A Urban and Rural, with Urban attendance times attracting a 15-minute arrival time and Grade A Rural attendance would attract a 20-minute arrival time. Some of these are listed below but is not exhaustive.

Another variant in use within the UK.

A numerical grading system is used in some forces.

Ambulance responses in the UK are as follows. Some ambulance services allow driver discretion for 'Green' calls; this may be dependent on the type of call or how long it has been waiting for a response for.

The use of flashing lights and sirens is colloquially known as blues and twos which refers to the blue lights and the two-tone siren once commonplace (although most sirens now use a range of tones). In the UK, only blue lights are used to denote emergency vehicles (although other colours may also be used as sidelights, stop indicators, etc.). A call-out requiring the use of lights and sirens is often colloquially known as a blue light run.

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