NEMA LSD 71
Best Practices for Metal Halide Lighting Systems Relative to Lamp Rupture Risks
|Publication Date:||1 January 2014|
Metal halide lighting systems represent one of the great innovations in lighting applications. Today's systems provide the ability to deliver a variety of light levels, from low to very high output, with highenergy efficiency, long life, and excellent color. In addition, since metal halide lamps are compact sources, these systems offer the ability to direct and focus light in a manner not possible with more diffused high-efficiency light sources, such as fluorescent lamps.
Since metal halide lamps operate at elevated internal pressures compared with most other generalpurpose light sources, manufacturers have historically provided explicit instructions on their proper use. In addition, manufacturers provide warning information designed to reinforce the need to follow these instructions, since failure to do so can significantly increase the risk of a lamp rupture. A lamp rupture can eject hot particles into the luminaire, and potentially into the surrounding space, if the luminaire does not completely enclose and contain all hot particles. If hot particles land on combustible materials, there is risk of fire. Despite the large number of metal halide lamps used, there are very few reported instances of property damage claims resulting from the rupture of metal halide lamps. When even this small risk of rupture is not acceptable, glass-enclosed luminaires should be used, or where glass-enclosed luminaires are undesirable, Type O lamps should be used.
One goal of NEMA manufacturers is to reduce risk as much as possible without unreasonably sacrificing product utility, by continually striving to improve the application and use of metal halide systems.