In the UK, the Road Vehicles Lighting Regulations 1989 (Statutory Instrument 1989 № 1796) govern the installation, performance and use of all vehicle lighting. The following paragraphs outline some of the basic rules.
Drivers must use front and rear position lamps (parking and tail lamps) between sunset and sunrise and at other times in conditions of seriously reduced visibility, defined in the Highway Code as being, generally, less than 100 metres (328 feet).
Headlamp Use Requirements
Drivers must use dipped (low) beam headlamps during the "hours of darkness" (half an hour after sunset until half an hour before sunrise) except on certain well-lit roads, i.e., roads where the street lights are less than 185 metres (600 ft) apart. Drivers must also used dipped beam headlamps in conditions of seriously reduced visibility. Headlamps must not cause undue dazzle or discomfort to other road users and must not be lit when a vehicle is parked. Headlamps must be kept clean and in good working order. However, a vehicle with a defective headlamp between sunrise and sunset is not committing an offence if the lamp became defective during the journey or if it will be repaired with all reasonable expedition.
European Union Situation
Within the European Union, Directive 76/756 EEC (1976), as last amended by 91/663/EEC (1991), governs the installation of lighting and light signalling devices. All EU Member States must permit the entry into service of vehicles which comply with this directive. Compliance with 76/756 as amended effectively became mandatory starting 1 January 1996 throughout the EU for new M1-class vehicles (essentially passenger cars) subject to EC Whole Vehicle Type Approval.
The UK Road Vehicle Lighting Regulations require vehicles first used on or after 1 April 1987 to be fitted with a dim-dip device or running lamps unless they fully comply with the 76/756 EEC lighting installation Directive. Dim-dip devices must provide an intensity of between 10 and 20 per cent of the intensity of the normal dipped beam. Running lamps must provide an intensity of not less than 200 candela directly in front of the lamps and parallel to the longitudinal axis of the vehicle, and not more than 800 candela in any direction.
At the 18th Sessional Meeting of the Commission Internationale de l'Éclairage (CIE) in London in 1975, a joint committee concerned with visual signalling, road lighting and automobile lighting came to the following conclusion:
It is recommended that a 'town beam' be introduced which is intermediate in intensity between that of the currently used low beam and side lights. Such a light should have a luminous intensity between 50 and 100 cd and should have an area similar to that of current headlights. Therefore it is recommended that all relevant organisations consider this matter seriously and take the necessary steps to introduce a town beam as an essential part of the lighting systems for road traffic.The committee believed such a beam would provide conspicuous and glare-free front lighting on vehicles. They suggested the beam could be simply realized by using the existing dipped beam headlamp on a lower voltage.
Gaynor, UK Ministry of Transport, Vehicle Standards & Engineering office
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