Post: Basic requirements for headlights

According to China’s “Technical Conditions for Motor Vehicle Operation Safety” (GB 7258–2012), the requirements for headlights mainly include lighting distance and position, anti-glare devices and luminous intensity.

1. Requirements for headlight lighting distance
   In order to ensure driving safety, the driver must be able to identify any obstacles on the road within 100m in front of the vehicle. The lighting distance of the car’s high beam is required to be greater than 100m. This data is based on the driving speed of the car. With the increase in the driving speed of modern cars, the requirements for lighting distance will increase. The lighting distance of the car’s low beam is about 50m. The position requirements are mainly to illuminate the entire section of the road within the lighting distance and not to deviate from the road surface.
2. Requirements for headlamp luminous intensity
   The luminous intensity of the high beam of the in-use vehicle is: not less than 15000cd (candela) for the two-lamp system, not less than 12000cd (candela) for the four-lamp system; the luminous intensity of the high beam of the newly registered vehicle is: not less than 18000cd (candela) for the two-lamp system, not less than 15000cd (candela) for the four-lamp system.
3. Anti-glare requirements for headlights
   Automobile headlights should have anti-glare devices to avoid dazzling the driver of the opposite car when two cars meet at night and cause traffic accidents. When used when two cars meet at night, the light beam is tilted downward to illuminate the road within 50m in front of the car, thereby avoiding dazzling the driver of the oncoming car.
4. With the development of high-speed vehicles, some countries have begun to pilot the three-beam system. The three-beam system is high-speed high beam, high-speed low beam, and low beam. When driving on the highway, use the high-speed high beam; when driving on the road without oncoming vehicles or when meeting on the highway, use the high-speed low beam; when there are oncoming vehicles and when driving in the city, use the low beam.