The operational concept of HID lamps are very similar to fluorescent lamps. HID lamps include Mercury Vapor, Metal Halide, High Pressure Sodium/Low Pressure Sodium (SOX).
In an HID lamp, the electrical arc, gasses and metals are contained in the arc tube.
Like fluorescents, HID lamps require a ballast to control the electrical current in the arc tube.
HID lamps need a start-up time to reach their full brightness. This usually takes 5 to 10 minutes.
Metal Halide
Uses metal halides of sodium iodide and scandium iodide
Most popular and widely used in the HID category
Used in general lighting as commercial/industrial/outdoor flood lighting where good color and high efficiency are desired
cUL Mark is the UL Mark for Canada. Products with this type of mark have been evaluated to Canadian safety requirements, which may be different from US safety requirements.