Lighting Glossary

Here are some lighting terms that are commonly used in the industry

Ballasts – Ballasts are electronic devices that fluorescent lights use to function. Without ballasts, fluorescent lights would easily fail or would never even light at all. The ballast keeps the bulb’s current balanced and allows the light to function. Magnetic ballasts are based on a simple magnetic transformer made of a steel core and copper wire wrappings to produce an electromagnetic current. The ballast also uses capacitors to limit and control the current as needed. Electronic ballasts use electronic circuits to convert the AC (and sometimes DC) line, to the voltages a fluorescent tube needs to light. Electronic ballasts are much more energy efficient than magnetic ballasts

Compact Fluorescent Lamp (CFL) – A family of single-ended fluorescent-discharge light sources with small-diameter [16-millimeter (5/8-inch) or less] tubes.

Efficacy – Efficacy is an industry term for the amount of light produced per watt of electricity (comparable to efficiency). It is the rate at which a light bulb is able to convert electrical power (watts) into light (lumens), expressed in terms of lumens per watt (LPW). For example, a 100 watt lamp producing 1750 lumens gives 17.5 lumens per watt.

Fluorescent Lighting – A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful light much more efficiently than incandescent lamps. The luminous efficacy of a compact fluorescent light bulb is about 60 lumens per watt, four times the efficacy of a typical incandescent bulb. For conventional tube fluorescent lamps the fixture is more costly because it requires an ballast to regulate the current through the lamp, but the lower energy cost typically offsets the higher initial cost. (From wikipedia)

LED – (Light Emitting Diode) LED lighting offers long service light and hight energy efficiency than regular lighting.

Lighting Glossary

LED Retrofitting – replacing conventional fluorescent, neon or other lighting with more efficient LED lighting

Lumen –  is a measure of the total visible light output of a light source.


Metal Halide Lamps – A type of HID lamp that is filled with metal halides in addition to the argon and mercury used in mercury vapour lamps. Metal halide lamps are more efficient and have better colour rendering than mercury lamps.

Neon Lights – Neon lighting consists of brightly glowing, electrified glass tubes or bulbs that contain rarefied neon or other gases. Neon lights are a type of cold cathode gas-discharge light. A neon tube light is a sealed glass tube with a metal electrode at each end, filled with one of a number of gases at low pressure. (From wikipedia)

Pulse Start Halide Lamps – Traditional probe-start metal halide lamps do not use an igniter and require three electrical contacts to ignite the gas and remain lit. Pulse-start metal halide lamps use only two contacts and use an igniter located inside the ballast pod.
Pulse-start lamps offer several benefits:

  • higher light output per unit of electric power
  • higher light output as lamps age
  • longer lamp life
  • more stable colour rendering as lamps age
  • quicker startup – pulse-start lamps can reach full brightness in two to four minutes instead the five to ten minutes needed by probe-start lamps (Natural Resources Canada)

T12 Bulbs – T12 light bulbs are long, cylindrical lighting that use a ballast and pin-type connection to generate light. This older technology allows those in the area to see adequate coloring and shading, but without the quality produced by the newer T8 bulb. (

T8 Bulbs – T8 bulbs look just like T12 bulbs, making them a suitable substitute in older light fixtures. Also, T8 bulbs have a diameter of 1 inch, as opposed to the T12’s 1.5 inch diameter. In addition, they use less power than a T12, saving consumers money over the lifespan of the bulb. (

Watt –  A measure of the total power output of a light source.