Beacon Colours Explained: Amber, Blue, Green and Who Uses Each

In Great Britain, warning beacon colours are fixed by law: amber is for slow, wide, breakdown and road works vehicles; blue is only for emergency vehicles, including bomb disposal and blood service vehicles; green is for doctors registered with the General Medical Council; and yellow is for airport vehicles off the public road. Red and purple are not general beacon colours.

The rules come from the Road Vehicles Lighting Regulations 1989 (RVLR), mainly regulations 11, 16 and 27 and Schedule 16. The table below gives the short answer, then each colour is explained in turn.

Beacon colours at a glance

Colour	Who may use it	When it may be lit	Legal basis
Amber	Vehicles with a maximum speed of 25 mph or less (and their trailers), vehicles over 2.9 m wide, road clearance (gritters, ploughs), road maintenance, utility work, breakdown and recovery, refuse collection, escort, special types, customs fuel testing, surveying, vehicle removal	At an emergency, when necessary or desirable to warn of the vehicle’s presence, and for breakdown and escort work	RVLR reg 11(2)(l), reg 27 item 7
Blue	Emergency vehicles as defined in RVLR, and vehicles used for special forces purposes	At an emergency, to show the urgency of the journey, or to warn of the vehicle or a hazard	RVLR reg 3, 11(2)(k), 16, 27 item 6
Green	Vehicles used by a medical practitioner registered by the General Medical Council	Only while occupied by the doctor and used for an emergency	RVLR reg 11(2)(m), reg 27 item 8
Yellow	Vehicles for use at airports	Never on a public road	RVLR reg 11(2)(n), reg 27 item 9
Red	No general beacon use. Red light to the front is banned except a red and white mast-mounted beacon or chequered lamp on a fire service control vehicle	At the scene of an emergency	RVLR reg 11(1)
Purple, white, other	Not permitted as a warning beacon colour	Not applicable	RVLR Schedule 16 para 6, reg 11

Schedule 16 lists the permitted beacon colours as blue, amber, green or yellow, each “in accordance with Regulation 11”. Northern Ireland has its own lighting regulations with similar colour rules.

Amber beacons: slow, wide and working vehicles

Amber is the warning colour for vehicles that are slow, oversized or working on the road. It is the only beacon colour farm vehicles may use, and it gives no priority. Highway Code rule 225 tells drivers that amber beacons warn of a slow-moving or stationary vehicle, or abnormal loads, so approach with caution.

Regulation 11 lists who may fit one. The main groups are:

• Vehicles with a maximum speed not exceeding 25 mph, and any trailer they tow (tractors with a 40 km/h maximum speed, slow plant, mobility scooters)
• Vehicles over 2.9 m wide including the load (combines, wide implements, wide loads)
• Road clearance vehicles, such as gritters and snow ploughs
• Vehicles testing, maintaining, improving, cleansing or watering roads
• Vehicles working on apparatus in, on, under or over a road (utilities, telecoms, street lighting)
• Breakdown vehicles, refuse vehicles and escort vehicles
• Vehicles authorised under a special types order, customs fuel testing, surveying, and vehicle removal or clamping

Some slow vehicles must use amber: under RVLR regulation 17, a vehicle with 4 or more wheels and a maximum speed of 25 mph or less needs a lit amber beacon on an unrestricted dual carriageway. See our guides to amber beacon meaning and the amber flashing beacon on a dual carriageway for the detail.

What colour beacon does a road gritter use?

A road gritter uses an amber beacon. Gritters and snow ploughs are road clearance vehicles under RVLR, and the Traffic Signs Manual Chapter 8 says vehicles gritting or snow clearing should display a flashing amber beacon at all times while operating.

What colour beacon does a breakdown recovery truck use?

A breakdown recovery vehicle uses an amber beacon. Regulation 27 allows it to be lit while the truck is at, or close to, an accident or breakdown, or while it is towing a broken-down vehicle.

Blue beacons: emergency vehicles only

Blue beacons may only be fitted to emergency vehicles. RVLR regulation 16 says no vehicle other than an emergency vehicle, or a vehicle used for special forces purposes, may be fitted with a blue warning beacon, a blue special warning lamp, or anything that resembles one, whether it works or not. Even a dummy blue beacon is illegal on a farm vehicle.

Who can use a blue beacon?

The RVLR definition of “emergency vehicle” includes:

• Police, fire and rescue, and ambulance vehicles, including vehicles responding to emergencies at the request of an NHS ambulance service
• Ministry of Defence vehicles used for bomb and explosives disposal, and for radiation emergencies
• Vehicles primarily used by the Blood Transfusion Service
• HM Coastguard and Coastguard Auxiliary Service vehicles giving aid to people or vessels in danger
• Mine rescue vehicles, mountain rescue vehicles and RAF Mountain Rescue
• RNLI vehicles used to launch lifeboats
• Vehicles carrying human tissue for transplant
• Fire salvage vehicles, and Forestry Commission or local authority vehicles used for fighting fires
• Vehicles used for Serious Organised Crime Agency purposes (the regulations still use that name; the agency was replaced by the National Crime Agency in 2013) and certain HMRC serious crime vehicles

What colour beacon does a bomb disposal vehicle use?

A bomb disposal vehicle uses blue beacons. Ministry of Defence vehicles used for the disposal of bombs or explosives are emergency vehicles under RVLR, so they are entitled to blue lights. This is a classic theory test question, and the answer is blue, not red.

Green beacons: doctors on emergency calls

A green beacon means a doctor attending an emergency. RVLR allows a green warning beacon on a vehicle used by a medical practitioner registered by the General Medical Council (with full or provisional registration), and regulation 27 says it may only be lit while the doctor is in the vehicle and it is being used for an emergency.

A green beacon gives no legal exemptions. The doctor must still obey speed limits and red lights. Highway Code rule 219 asks drivers to look and listen for doctors and other emergency vehicles and to let them pass where it is safe.

Do farm vehicles use green beacons?

No. Green beacons are not permitted on farm vehicles on the road. Some construction and quarry sites use green lights on plant as a site signal, for example to show the operator’s seat belt is fastened, but that is a site rule and has no meaning on the public road.

Yellow beacons: airports only

Yellow beacons are for vehicles used at airports. Regulation 27 says a yellow beacon must not be lit on a road, so an airside vehicle driving on a public road must switch it off.

Red beacons

Red is not a beacon colour for ordinary vehicles. RVLR regulation 11 bans any lamp that can show red light to the front, with a short list of exceptions. The only beacon in that list is a red and white segmented mast-mounted warning beacon, or a red and white chequered domed lamp, on a fire service control vehicle at the scene of an emergency.

Highway Code rule 219 mentions emergency vehicles using “flashing blue, red or green lights”. Regulation 11 also allows light of any colour from a traffic sign attached to a vehicle, which covers the vehicle-mounted signs used by some incident and road works vehicles. None of this applies to farm vehicles.

Purple beacons

Purple is not a permitted beacon colour in Great Britain. Schedule 16 allows only blue, amber, green or yellow, and regulation 11 bans lamps showing any colour to the rear other than red unless it is on the permitted list. Purple beacons are sold for show and some overseas uses, but fitting one to a vehicle on a UK road is not legal.

What colour beacon can I use?

For a tractor, telehandler, farm trailer, contractor’s van or recovery truck, the answer is amber, and only amber. Check that your vehicle or use is on the regulation 11 list (a tractor with a 40 km/h maximum speed is, as is any vehicle over 2.9 m wide; a tractor capable of more than 25 mph is only on it if it qualifies another way, such as width). Then choose a beacon that meets RVLR Schedule 16: centre at least 1,200 mm above the ground, visible all round, flashing 60 to 240 times a minute.

When buying, look for ECE R65 approval, which proves the colour and intensity have been tested, and R10 for electromagnetic compatibility. Our ECE R65 beacons guide explains the marks, and the tractor beacons buying guide covers LED or halogen, mounts and voltage. Browse our amber tractor beacons or the wider universal beacons range.

Penalties for the wrong colour

Using a vehicle that does not comply with the lighting regulations is an offence. Regulation 16 is strict on blue: the ban covers any blue beacon or lookalike fitted to a non-emergency vehicle, even if it is not wired up. If you buy a tractor or van with the wrong colour beacon fitted, remove it and fit an approved amber beacon before using the vehicle on the road.

Frequently asked questions

What is the meaning of a green beacon?

A green beacon means a doctor, registered with the General Medical Council, is using the vehicle for an emergency. Let them pass where it is safe, but the beacon gives them no right to break traffic law.

Can a farmer use a blue beacon?

No. RVLR regulation 16 bans a blue beacon, or anything resembling one, on any vehicle other than an emergency vehicle or a special forces vehicle. Farm vehicles must use amber.

What colour is a blood bank or blood service vehicle beacon?

Blue. Vehicles primarily used for the Blood Transfusion Service are emergency vehicles under RVLR, so they may use blue beacons.

Are white or clear beacons legal?

No. White is not a permitted warning beacon colour under Schedule 16. White flashing lights built into some light bars must not be used on the road.

Do amber beacon vehicles have priority?

No. Amber beacons are warnings only. You do not need to give way or pull over, but you should slow down and approach with caution.