Emergency vehicle equipment is used in the United Kingdom to indicate urgent journeys by an emergency service. This usage is colloquially known as "blues and twos", which refers to the blue lights and the two-tone siren once commonplace (although most sirens now have a range of tones like Wail, Yelp, Phaser, and Hi-Lo). A call-out requiring the use of lights and sirens is often colloquially known as a "blue light run". From 1993 to 1998, a television documentary following Britain's emergency services was titled Blues and Twos for this reason.
Permitted use Legislation that regulates blue flashing lights and sirens The Road Vehicles Lighting Regulations 1989 Road Vehicle Construction and Use Regulations 1986 Road Vehicles Lighting (Amendment) Regulations 2005 The Road Vehicles (Construction and Use)(Amendment)( No.2) Regulations 2005 Serious Organised Crime and Police Act 2005 (Consequential and Supplementary Amendments to Secondary Legislation) Order 2006 Road Vehicles (Construction and Use)(Amendment)(No.4) Regulations 2009 Road Vehicles Lighting and Goods Vehicles (Plating and Testing) (Amendment) Regulations 2009 Road Traffic Exemptions (Special Forces) (Variation and Amendment) Regulations 2011 Section 50 of the Deregulation Act 2015 Schedule 9 of the Deregulation Act 2015 Road Vehicles Lighting Regulations (Northern Ireland) 2000 Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999 The Road Vehicles Lighting (Amendment) Regulations (Northern Ireland) 2007 The Road Vehicles Lighting (Amendment No. 3) Regulations (Northern Ireland) 2011 In Great Britain, the use of blue lights is regulated by the Road Vehicles Lighting Regulations 1989, and sirens by the Road Vehicles Construction and Use Regulations 1986, both of which have been amended by various other pieces of legislation (see right).
Regulation 16 of the Road Vehicle Lighting Regulations 1989 state that no vehicle, other than an emergency vehicle (or a vehicle used for special forces purposes), shall be fitted with a "blue warning beacon or special warning lamp", or a device which resembles a blue warning beacon or a special warning lamp, whether it works or not.
Similarly, Regulation 37(4) of the Road Vehicle Construction and Use Regulations 1986 prohibit vehicles from having a siren, bell, gong, or two-tone horn, unless the vehicle met the conditions of paragraph 5 (for emergency vehicles).
Northern Ireland on the other hand has the Road Vehicle Lighting Regulations (Northern Ireland) 2000 and the Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999.
Great Britain Type of vehicle Blue flashing lights Sirens Other exemptions used for police purposes The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 Yes used for National Crime Agency purposes The Serious Organised Crime and Police Act 2005 (Consequential and Supplementary Amendments to Secondary Legislation) Order 2006 The Serious Organised Crime and Police Act 2005 (Consequential and Supplementary Amendments to Secondary Legislation) Order 2006 Yes used for Scottish Fire and Rescue Service purposes or fire and rescue authority purposes in England or Wales The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 Yes used for: ambulance purposes, or for the purpose of providing a response to an emergency at the request of an NHS ambulance service (which includes motorbikes, "fast response" cars and similar)Schedule 9 to the Deregulation Act 2015 The Deregulation Act 2015 The Deregulation Act 2015 Yes an ambulance, being a vehicle (other than an invalid carriage) which is constructed or adapted for the purposes of conveying sick, injured or disabled persons and which is used for such purposes The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 Yes owned by a body formed primarily for the purposes of fire salvage and used for those or similar purposes The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 No owned by: the Forestry Commission or by a local authority Natural Resources Wales for the purposes of its functions relating to forestry and woodlands the Scottish Ministers for the purposes of their functions under the Forestry and Land Management (Scotland) Act 2018 (i.e. Forestry and Land Scotland) and used from time to time for the purposes of fighting fires The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 No owned or operated by the Secretary of State for Defence and used: for the purposes of the disposal of bombs or explosives for the purposes of any activity which prevents or decreases the exposure of persons to radiation arising from a radiation accident or radiation emergency, or in connection with an event which could lead to a radiation accident or radiation emergency by the Royal Air Force Mountain Rescue Service for the purposes of rescue operations or any other emergencies The Road Vehicles Lighting (Amendment) Regulations 2005 The Road Vehicles (Construction and Use)(Amendment)( No.2) Regulations 2005 Some owned or operated by the Secretary of State for Defence and used by United Kingdom Special Forces in response, or for training or practice in responding, to a national security emergency The Road Traffic Exemptions (Special Forces) (Variation and Amendment) Regulations 2011 The Road Traffic Exemptions (Special Forces) (Variation and Amendment) Regulations 2011 Yes primarily used for the purposes of the Blood Transfusion Service provided under the National Health Service Act 1977 or under the National Health Service (Scotland) Act 1978 The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 Some used by His Majesty's Coastguard or Coastguard Auxiliary Service for the purposes of giving aid to persons in danger or vessels in distress on or near the coast The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 No used for the purposes of rescue operations at mines The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 No owned by the Royal National Lifeboat Institution and used for the purposes of launching lifeboats The Road Vehicles Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 No exemptions. However, as it is only lifeboat launching vehicles that are classed as emergency vehicles and with all but a handful of these vehicles being slow moving tractors that move lifeboats across roads and beaches to access the sea it is highly unlikely they will ever need to use exemptions in the course of their emergency duties in any case. primarily used for the purposes of conveying any human tissue for organ transplant or similar purposes The Road Vehicles Lighting Regulations 1989 No No under the lawful control of the Commissioners for His Majesty's Revenue and Customs and used from time to time for the purposes of the investigation of serious crime The Road Vehicles Lighting (Amendment) Regulations 2005 The Road Vehicles (Construction and Use) (Amendment) (No.2) Regulations 2005 No used for mountain rescue purposes The Road Vehicles Lighting and Goods Vehicles (Plating and Testing) (Amendment) Regulations 2009 The Road Vehicles (Construction and Use) (Amendment) (No.4) Regulations 2009 No exemptions for Mountain Rescue purposes alone; unless coupled with police purposes for all mountain rescue purpose vehicles except mountain rescue ambulances, while mountain rescue ambulances may couple mountain rescue purposes with "an ambulance, being a vehicle (other than an invalid carriage) which is constructed or adapted for the purposes of conveying sick, injured or disabled persons and which is used for such purposes" and/or ambulance purposes used for the purpose of training drivers for the use of blue lights for any of the above purposes. The Road Vehicle Lighting Regulations 1989 The Road Vehicles (Construction and Use) Regulations 1986 Some
Northern Ireland +Type of vehicleBlue flashing lightsSirensOther exemptionsA vehicle used for fire and rescue authority purposesThe Road Vehicles Lighting (Amendment No. 3) Regulations (Northern Ireland) 2011The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999YesA vehicle used for ambulance purposesThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999YesA vehicle used for police purposesThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999YesAn ambulance, being a vehicle (other than an invalid carriage) which is constructed or adapted for the purposes of conveying sick, injured or disabled persons and which is used for such purposesThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999YesA cardiac response vehicle, being a vehicle used only for the purposes of transporting medical or nursing personnel and equipment to cardiac incidentsThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999YesA vehicle owned by a body formed primarily for the purposes of fire salvage and used for those or similar purposesThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999?A vehicle owned by the Department of Agriculture and used from time to time for the purposes of fighting firesThe Road Vehicles Lighting Regulations (Northern Ireland) 2000The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999?A vehicle owned or operated by the Secretary of State for Defence and used-
for the purposes of the disposal of bombs or explosives for the purposes of any activity which prevents or decreases the exposure of persons to radiation arising from a radiation emergency, or in connection with an event which could lead to a radiation emergency by the Royal Air Force Mountain Rescue Service for the purposes of rescue operations or other emergenciesThe Road Vehicles Lighting (Amendment) Regulations (Northern Ireland) 2007The Motor Vehicles (Construction and Use) Regulations (Northern Ireland) 1999