22 August 2006
Considerations for induction lamps:
Consider induction lamps for exterior area lighting, especially in "instant-
Consider induction lamps in low bay luminaires.
Specify 3000 K lamps for exterior applications.
Metal Halide and Mercury Vapor Lamps. Metal Halide lamps provide a small
point source of white light. Metal halide lamp efficacies and lamp life are increasing with
pulse start technology. The disadvantages of the metal halide lamp are lumen
depreciation and a long start up time. Additionally, these lamps also have a re-strike
time. When a lamp is warm and then turned off, it must cool sufficiently before it can be
re-ignited. This time delay is the re-strike time of the lamp. Even with these
disadvantages, metal halide is a great source of white light, especially for exterior
nighttime lighting, where it enhances peripheral vision.
5-3.6.1 Do not use mercury vapor lamps because of their poor color rendering
properties and poor energy efficacy.
5-3.6.2 The ideal applications for metal halide lamps include exterior parking lots,
roadway lighting, area lighting, indirect atrium lighting, and accent lighting.
Requirements for metal halide and mercury vapor lamps:
Do not use mercury vapor lamps.
Use electronic ballasts for metal halide lamps 150 watts and below.
These ballasts are more reliable and use less energy than magnetic
ballasts. Currently they are only available for 150 watt lamps and lower.
(If higher wattages become available from (3) manufacturers, they should
Considerations for metal halide lamps:
Consider metal halide lamps for exterior lighting in areas of pedestrian
traffic and where light color and color rendering are important.
Consider pulse start metal halides if possible. These lamps have
improved lumen maintenance and longer lamp life. (Available for vertical
Consider metal halide PAR lamps (50 watts or lower) for accent lighting,
Use metal halide lamps (100 watts and higher) in fully shielded or IESNA
full cut-off luminaires.