"The information on this website is meant to provide a general overview of the tax provisions for the interim rules of lighting systems listed in the Energy Policy Act of 2005. In all cases the services of a professional tax accountant should be retained to determine the specific tax treatment appropriate for your company. Requirements for lighting levels and controls, in accordance with EPAct 2005, must also be satisfied for eligibility. Rexel will not, in any way, accept any liability for decisions made based on the contents of this preliminary explanation."


Lighting Glossary

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


Maximum Overall Length (M.O.L.)
The end-to-end measurement of a lamp, expressed in inches or millimeters.

Mean Lumens
The average light output of a lamp over its rated life. Based on the shape of the lumen depreciation curve, for fluorescent and metal halide lamps, mean lumens are measured at 40% of rated lamp life. For mercury, high-pressure sodium and incandescent lamps, mean lumen ratings refer to lumens at 50% of rated lamp life. See Lumen Maintenance.

Mercury Lamp
A high-intensity discharge light source operating at a relatively high pressure (about 1 atmosphere) and temperature in which most of the light is produced by radiation from excited mercury vapor. Phosphor coatings on some lamp types add additional light and improve color rendering.

Metal Halide Lamp
A high-intensity discharge light source in which the light is produced by the radiation from mercury, plus halides of metals such as sodium, scandium, indium and dysprosium. Some lamp types may also utilize phosphor coatings.

> Return to Top