Metal Halide (High Intensity Discharge) lights for full spectrum light - select from the menu on the left, or use Search to quickly locate your product!

High Intensity Discharge or "HID" is the term commonly used to designate four distinct types of lights that actually have very little in common. They are high pressure sodium, low pressure sodium, metal halide, and mercury vapor. Each requires a few minutes (one to seven) to come up to full output. Also, if power to the light is lost or turned off, the arc tube must cool to a given temperature before the light can be re-struck and light produced. Up to seven minutes (for mercury vapor lights) may be required.

Metal halide lights produce a bright white light which provides full spectrum colour output and are highly efficient members of the HID family. The efficiency of metal halide lights is from 1.5 to 2 times that of mercury vapor lights. The metal halide light is very similar in construction to the mercury vapor lights. The major difference is that the metal halide lights contains various metal halide additives in addition to mercury vapor.

Metal halide lights are commonly used in stadiums, warehouses and any industrial setting where distinguishing colors is important, as they output a full spectrum of colour. Low wattage lights are available and have become popular in department stores, grocery stores, and many other applications where light quality is important.

Metal halide light sizes range from 175 to 1,500 watts. Ballasts designed specifically for metal halide lights must be used. Mercury vapor lights, recognizable by the bluish cast to their light output, are the least efficient members of the High Intensity Discharge (HID) family. They were developed to overcome problems with fluorescent lights for outdoor use and are actually less efficient than fluorescents.

Existing mercury lights systems should always be considered for retrofit with other high efficiency alternatives, unless they operate very few hours a year. Mercury vapor lights have found greatest use in industrial applications and outdoor lighting, because of their low cost and long life (16,000 to 24,000 hours). Light sizes range from 40 to 1,000 watts.

High pressure sodium lights are the most efficient members of the HID family where some degree of color rendition is important. Standard HPS lights produce a golden white light when they reach full brightness. Many recognize them as the familiar golden light from street lights, one of their principal applications. Low pressure sodium lights are the most efficient source of light commercially available, up to 183 lumens per watt.

However, they are used in very few applications because of their poor color rendering characteristics. The primary use of LPS lights is for street and highway lighting as well as outdoor area and security lighting. Low pressure sodium lights range in size from 35 watts to 180 watts. Ballasts designed specifically for LPS must be used.