History and Regulations
– Early road vehicles used fuelled lamps for lighting
– The first Ford Model T used carbide lamps for headlights and oil lamps for tail lights
– Dynamos for automobile headlights were first fitted around 1908
– Trafficators, signalling arms that flipped up, were introduced in about 1900
– Silent film star Florence Lawrence introduced an innovative version of the signalling arm in 1914 and a mechanical brake signal
– The colour of vehicle lights is largely standardized by established conventions
– Lights facing rearward must emit red light
– Side-facing lights and turn signals must emit amber light
– Lights facing forward must emit white or selective yellow light
– No other colours are permitted except on emergency vehicles
– Forward illumination is provided by high- and low-beam headlights
– Auxiliary fog lights, driving lights, or cornering lights can also be used
– High beam headlights provide intense, centre-weighted distribution of light
– Low beam headlights provide adequate illumination without dazzling other road users
– Fog lights provide wide, bar-shaped beam of light for poor visibility conditions
– Low beam headlights have a sharp, asymmetric cut-off to prevent glare for oncoming drivers
– High beam headlights have no glare control and are suitable for use when alone on the road
– UN ECE regulations permit higher-intensity high-beam headlights than US and Canadian standards
– US and Canadian standards also specify a sharp, asymmetric cut-off for low beam headlights
– Headlights conforming to UN ECE regulations provide better illumination and less glare for oncoming drivers
– Driving lights provide high-intensity light for longer range visibility
– Front fog lights produce a wide beam of light for poor visibility conditions
– Front fog lights are sometimes used in place of dipped-beam headlights
– Selective yellow fog lights are not legally required in most countries
– Use of fog lights when visibility is not reduced is often prohibited in many jurisdictions
– International UN Regulations have provisions for front and rear cornering lights
– Cornering lights were traditionally prohibited under UN Regulations, but exceptions have been made
– Some countries have specific regulations for the use of DRLs
– UN Regulation 87 sets standards for DRL intensity and color
– Different countries have different regulations regarding the use of auxiliary lights
– Amber front and red rear side marker lights and retroreflectors are required in the United States.
– Initially, the law required lights and retroreflectors on vehicles manufactured after January 1, 1968.
– The requirement was amended to include vehicles manufactured after January 1, 1970.
– Side-facing devices make the vehicle’s presence, position, and direction of travel visible from oblique angles.
– Side marker lights illuminate when the vehicle’s parking lights and tail lights are on, including when the headlights are being used.
– Turn signals are blinking lights mounted near the corners of a vehicle.
– They are activated by the driver to indicate intent to turn or change lanes.
– Turn signals can also be used as hazard warning signals when a vehicle is parked on the road.
– Electric turn signal lights date back to 1907.
– Most countries now require turn signals on all new vehicles driven on public roadways.
– Factory installation of illuminated turn signals began in the 1930s.
– The modern flashing turn signal was patented in 1938.
– Most major automobile manufacturers offered turn signals before they became mandatory in the 1950s.
– Hand signals were used earlier and are still common for bicycles.
– Some cars from the early 1900s to the 1960s used retractable semaphores called trafficators instead of flashing lights.
– Side-mounted turn signal repeaters are required in most countries.
– In the United States and Canada, front amber side marker lights may be wired to flash with the turn signals as an alternative.
– Mercedes-Benz introduced side turn signal repeaters integrated into side-view mirrors in 1998.
– Mirror-mounted turn signals may be more effective than fender-mounted ones.
– Side turn signal devices are now commonly incorporated into mirror housings.
– Turn signals must flash at a steady rate of 60-120 pulses per minute.
– International regulations require all turn signals to flash in simultaneous phase.
– US regulations permit side marker lights wired for side turn signal functionality to flash in opposite-phase.
– An audio and/or visual tell-tale indicator is required to advise the driver when the turn signals are activated.
– Dashboard indicators typically consist of one or two green lights and a rhythmic tic sound.
Types of Auxiliary Lights
– Front fog lights and driving lights are often confused
– Cornering lights provide lateral illumination during turns
– Spot lights are used by police cars and emergency vehicles
– Conspicuity lights make vehicles visible to others
– Daytime running lights improve visibility during daylight hours
Front Position Lights and Daytime Running Lights (DRLs)
– Front position lights provide nighttime standing-vehicle conspicuity
– They emit white light, except for motorcycles which may have amber lights
– In some countries, front position lights can emit amber light
– In Germany, front position lights serve as low-intensity lights when parked in narrow unlit streets
– In the US, front position lights can emit amber light if combined with a side marker
– DRLs can be functionally dedicated lights or integrated with existing lights
– Some countries require vehicles to be equipped with DRLs
– DRLs must emit white light with a specific intensity range
– Complaints about glare have been raised in the US due to high-intensity DRLs
– DRL regulations vary by jurisdiction, including rules about combination with other lights
– Dim-dip lights were required in the UK for vehicles first used after 1 April 1987
– They operated at 10-20% of normal low-beam intensity
– Dim-dip lights were not intended for daytime use as DRLs
– The UK requirement for dim-dip lights was deemed illegal by the European Court of Justice
– Dim-dip lights were mainly used in vehicles sold in Commonwealth Source: https://en.wikipedia.org/wiki/Automotive_lighting
A motor vehicle has lighting and signaling devices mounted to or integrated into its front, rear, sides, and, in some cases, top. Various devices have the dual function of illuminating the road ahead for the driver, and making the vehicle visible to others, with indications to them of turning, slowing or stopping, etc., with lights also indicating the size of some large vehicles.
Many emergency vehicles have distinctive lighting equipment to warn drivers of their presence.
