Automobile Headlight Specificationsby Chris Stevenson
Headlight specifications and regulations can be set by the standards and requirements of each individual state, but all motor vehicle lighting falls under the jurisdiction of the Federal Motor Vehicle Safety Standard, according to provision No. 108. Although many states differ in their interpretation of headlight specifications, they all fall within the guidelines set forth by the Federal authorities.
Headlight Position and Number
Taking the Connecticut laws regarding headlights, for example, the specifications indicate that all motor vehicles, with the exception of motorcycles, must display two headlights with one on each side of the vehicle's front end. They should be mounted not more than 54 inches in height above the road's surface, and not any lower than 22 inches above the surface. Motorcycles must be equipped with one front headlight.
Headlight Intensity and Color
With the exception of motorcycles, every vehicle will have lamps mounted that will emit a white or amber light that can be seen from at least 1,000 feet from the front portion of the vehicle. A rear red light will be mounted which can be seen from at least 1,000 feet from the vehicle's rear end. All lamps should be dimmed or shut off on any vehicle in a parked condition. Only white, yellow or amber-colored lights can come from the front of the vehicle, unless a special permit has been issued by the Department of Motor Vehicles.
Auxiliary or High Beams
A combination of auxiliary headlights, or high and low beams, must be accessible to the driver by a switch that allows the driver to select the beam for different elevation requirements. The height requirements of the high beams must adhere to specific limitations according to law. The top beam, or high beam illumination, should be powerful enough to be seen from a distance of 500 feet in all weather conditions. The low intensity, or low beams, shall have an intensity allowing the vehicle to be seen from a distance of 100 feet, while positioned on a level and straight road. The high beam cannot be allowed to strike the eyes of an oncoming driver.
Use of Composite or High Beam
Upon driving over the shoulder of a road or on a road at times when headlights should be turned on, the driver must select the high beam lights to illuminate persons and vehicles at a safe distance. However, when approached within 500 feet of vehicles or persons, he must dim the lights so they do not glare or interfere with persons or oncoming driver's visibility. Upon approaching another vehicle from at least 300 feet behind, the driver will dim or switch the lights to the low beam setting.
Vehicles equipped with auxiliary lamps, a spotting light or any other lights used for lighting or clearance should not emit a beam with an intensity more than 300 candle power. Such vehicles will be restricted to four such lighting devices, in addition to the regular lighting equipment.
Federal Lighting Specifications
Upper beams shall range from 20,000 to 75,000 candela in intensity for each lamp. The lower beam will range from 15,000 to 20,000 candela in intensity for each lamp. These restrictions apply to Type 2 or 2A light classifications. The Type 1 or 1A limitations for lighting stipulates an upper beam that will range from 18,000 to 60,000 candela intensity for each lamp.
- headlights image by Christopher Hall from Fotolia.com