Fluorescent Lamps

Types and Uses

What is a fluorescent lamp? Fluorescent lamps work by sending an electrical discharge through

mercury vapor. An electrical current is shot through the gas, exciting the mercury atoms.

The UV light produced by the vapor is absorbed by phosphor layers that coat the inside of the bulb.

These phosphor layers produce visible light.

Before Electricity

After Electricity

Choosing Your Fluorescent Bulb There are five things to look at when deciding

on a bulb: Color Brightness Rated Life Bulb Diameter Bulb Length

Color Color is determined by the mixture of phosphor coating, made up

of certain salts and metals, including lanthanum, cerium, europium, terbium, and yttrium.

Color is a variation on white, depending on the temperature, measured in Kelvin (K). Higher Kelvins means brighter and colder lights; lower Ks mean softer and warmer lights

Type Color Temperature

Daylight Bluish >5000K

Cool White Pale Blue 3000-5000K

Warm White Pinkish <3000K

Full Spectrum White 5000-10000K

Brightness Fluorescent bulbs need time to achieve peak

brightness, a few hours at most.

At about 40% of a light bulb’s life, the fluorescent bulb burns at 90% brightness.

It’s working!!!

Hours Later…

Peak brightness achieved!!!

Rated Life The rated life of a fluorescent bulb is between

20,000 to 30,000 hours or about 3 ½ years.

Want to extend that life? Leave the lamp on continuously. Switching a bulb on and off and on and off and so on, causes the bulb to dim faster.

Diameter and Length There currently exists a wide selection of tube

sizes and shapes, each referred to by the letter “T”, which means the bulb is a tube.

There is a number after the “T” that refers to the diameter, ranging from T2 to T12.

Length ranges from 6 to 96 inches, from the tip of the lamp to the back of the lampholder.

T2 T4 T5 T6 T8 T9 T10 T12

¼” ½” 5/8” ¾” 1” 1 1/8” 1 ¼” 1 ½”

6-13W 6-28W 4-54W 25W 10-32W

20W 40W 14-60W

Any questions? If you need more help choosing, there are a

variety of articles with more information OR You can contact the contractors at B.K.

Electric Services 310-430-2300 www.bkelectricservices.com