The following practices should be followed, regardless of the specific type of metal halide system that is implemented and regardless of the specific use or application environment (store lighting, warehouse, industrial, etc.).

Users must become familiar with and heed the lamp and luminaire manufacturers’ warnings and follow their instructions with respect to safety, installation, maintenance, and reduction of risk. The user’s failure to follow the manufacturers’ warnings and instructions will increase the risk for those installations. This information can be found on the product packaging or insert sheet, in separate literature for the product, on web sites, or in published catalogs.

Always group re-lamp metal halide installations at the time recommended by the lamp manufacturer. Although some spot re-lamping may be necessary for any installation, using spot re-lamping as the only replacement practice increases risk and is strongly discouraged.

Follow lamp manufacturer instructions for lamp cycling. Products are available that will automatically cycle lamps/luminaires, either on a scheduled or random basis depending upon what is best for a user’s needs. Such automatic cycling controllers, which can be as simple as a time clock, can be installed for both new and existing metal halide applications.

Operate metal halide lamps on ballasts that are designed to provide the appropriate
wattage for the lamp. Operating the lamp on an incorrect ballast can increase the risk of lamp failure.

When installing and maintaining luminaires, ensure that all manufacturer-supplied components are installed properly. Failure to install supplied components, such as a lens, will void third party listing. The user’s failure to install a lens properly during luminaire installation or during routine maintenance could increase the risk of hot particles escaping the luminaire in
the unlikely event of a lamp rupture.

The luminaire manufacturer must be consulted if a user wishes to add a protective lens to an existing luminaire. In some instances, the addition of a lens may still leave an opening at the top of the reflector, which could allow the ejection of hot particles. Adding a cover lens to a luminaire where none was intended can raise both the lamp and ballast temperatures to unacceptable levels, increasing risk of failure. In addition, lens covers, when used, must themselves be operated within approved temperature limits for correct performance as a safety device. Failure to consult the luminaire manufacturer when adding such a cover may void its third party listing.

Follow lamp manufacturer recommendations and guidelines for dimming metal halide lamps. Excessively deep dimming (beyond manufacturer and industry guidelines) may increase the risk of rupture for some metal halide lamps. If dimming is to be employed, consult the lamp manufacturer for recommendations.

Special care should be taken when storing flammable, combustible, or oxidizing materials under metal halide luminaires. For example, in warehouse applications, locate luminaires over the center of the aisles. For more information, manufacturers should be consulted for the given situation.

Do not use luminaires in an application where the ambient temperature exceeds the luminaire rated temperature.