Light Bulbs Key Terms

Learn the lingo of light bulbs

By Mark Jenkins

Whether you work in construction, do interior decorating or are simply looking to keep your office well-lit, knowing how to choose the right light bulbs for your needs is important. Although it's easy to take light bulbs for granted, poor lighting can lower productivity and increase energy costs, draining money away from your business. Browse through the following key terms to learn more about light bulbs and to become an educated shopper.

Compact fluorescent lamp

Compact fluorescent lamps (CFL's) last longer and consume less energy than traditional incandescent bulbs. Because they can save up to 150 pounds of carbon per year, they are also great for the environment. CFL's come in a variety of styles designed for both indoor and outdoor use.
Try: Check out the guide to CFL's at Energy Star for more information.

Lumen

A lumen is a unit of measurement for how well a light bulb illuminates its surroundings. Bulbs with high numbers of lumens do a better job lighting up dark objects than those with low numbers of lumens, but they usually consume more energy, too.
Try: Learn the difference between lumens, foot-candles and candelas at The LED Light.

Color rendering index

A light bulb's color rendering index, or CRI, measures how well it brings out the color of surrounding objects. CRI is a relative term however, since each manufacturer tests its bulbs against their own reference light sources when measuring color rendering.
Try: Read through information on CRI from Full Spectrum Solutions to learn more about the measurement and how it relates to lighting quality.

Color temperature

Along with CRI, color temperature is an important factor when choosing light bulbs for professional lighting applications. In simple terms, color temperature, measured in degrees Kelvin (K), indicates the hue of a given light source. Temperatures between 5,500 and 6,500 K are the closest in color to natural daylight.
Try: See a complete list of light sources and their color temperatures at 3DRender.com by Jeremy Birn.

Finish

Finish refers to the color and composition that coats the interior of the bulb. A bulb's finish can not only changes it outward appearance and hue, but it can also change its lighting properties as well, making it softer, sharper or more diffuse.
Try: There's information on light bulb finishes on the website of McLendon Hardware.

Wattage

The amount of energy light bulbs use is a measurement of wattage. Most incandescent bulbs use between 60 and 100 watts.
Try: Dig into the physics behind light bulbs on Ask a Scientist from the U.S. Department of Energy.