Skip to main content

Facilities Planning

Metal Halide Lamps


Reference Guide #B.7

Section 409-b of the Education Law requires that every new or replacement mercury vapor or metal halide lamp, which is used within any school building in the State, shall be of the safety type. Safety-type lamps self-extinguish upon the breaking, cracking, or removal of the outer shield protecting the lamp. If such self-extinguishing variety is not available, each such lamp or its fixture shall be equipped with a shield adequate to protect against ultraviolet radiation exposure. In school complexes, these lamps might be used in lighting fixtures located in gymnasiums, auditoriums, swimming pools, shops, bus garages, and outdoor lighting.

Sylvania Lighting and General Electric have issued warnings regarding high-intensity discharge lighting which includes mercury and metal halide.

General Electric's message said, in part:

"Metal halide and mercury lamps are constructed of a glass bulb with an internal arc tube made of quartz. These bulbs operate under high pressure at very high temperatures as high as approximately 900oC in metal halide lamps. There exists the possibility with any of these lamp types, regardless of wattage, that the arc tube may unexpectedly rupture, due to internal causes or external factors, such as a systems failure or misapplication. When this occurs, the glass outer jacket surrounding the arc tube could break and particles of extremely hot quartz from the arc tube and glass fragments from the outer jacket will be discharged into the fixture enclosure and/or the surrounding environment, thereby creating a risk of personal injury or fire."(General Electric Bulletin dated December 20, 1985).

If you are using Sylvania Metal Arc lamps now, contact your distributor for specific installation and operating instructions.

If the lamps are other than Sylvania and you have any questions regarding the safety issues associated with the use of the lamps, contact the company's lamp representative or the fixture manufacturer.