How is the height of street lights designed? For what reason?

1. The installation height of lighting fixtures on the same street must be consistent (the height from the center of light emission to the ground). Small curved lights, 1-meter lights; long-arm lights for regular streets with a length of 5-6 meters and chandeliers; curved lights for fast lanes with a length of 6.5-7.5 meters; the height of curved lights for slow lanes should be no less than 8 meters, while that for curved lights in slow lanes should be no less than 6.5 meters. 2. Special types of lights are installed according to design requirements, and their height is roughly equal to the width of the road to be illuminated. When illuminated from only one side, H≌L; when illuminated from both sides, H≌L/2. Here, H is the height at which the lighting fixture is installed (in meters), and L is the width of the road (in meters)

Installation height, spacing, and cantilever length of street lights: To reduce glare, improve the quality of lighting, and prevent trees along the road from blocking the light, consideration should be given to the installation height, spacing, and cantilever length. (1) For cantilevered high-mast street lights, the installation height should generally be above 7 meters; if light-reducing fixtures are used, the installation height h should be ≥ Wj, and the spacing between lamp posts should not exceed 3 times the installation height ； If non-light-shielding lamps are used, the installation height h should be greater than 1.2Wj, and the spacing between lamp posts should not exceed 4 times the installation height ； If semi-opaque lighting fixtures are used, the installation height h should be greater than 1.2Wj, and the spacing between the light posts should not exceed 3.5 times the installation height. (2) The length of the cantilevered part of the light posts should be determined based on the road width and the type of trees; it is generally between 1.5 and 3.5 meters.

The main considerations are the distance of the street lights and the brightness of the lighting fixtures, as well as the required level of illumination.