What to Know About Fluorescent Lighting

Updated: Dec. 21, 2023

Wondering about fluorescent light? Learn the pros and cons of this type of lighting, along with the three main types of fluorescent bulbs.

Fluorescent lighting is light produced in a glass tube with electrical current passing through it, which reacts with mercury vapor to create light. The electrified vapor produces ultraviolet light which is absorbed by a chemical coating on the inside of the tube. That’s what creates the light we see when fluorescent bulbs are switched on.

All fluorescent light tubes (also called fluorescent lamps) require an electrical ballast to regulate the current flowing through them. Ballasts keep the current low enough so the lamp remains stable.

Types of Fluorescent Lightbulbs

When shopping for fluorescent bulbs, there are two main considerations: bulb type and color temperature. Like other types of lightbulbs, fluorescents come in various colors, typically ranging from cool blue to warm white. Personal preferences vary here, and your color choice depends on the atmosphere you’re after. Beyond color, fluorescent bulbs come in these three main styles:

Compact Fluorescent Bulbs

Typically fitted with standard threaded bases to fit into your existing light fixtures and lamps, compact fluorescent bulbs (CFLs) are small and have a thin folded or curled tube from which light emits. They also have built-in electronic ballasts, which is why they don’t require a full system change to start lighting your home.

Standard Tubes

Straight, simple tube-style fluorescent bulbs are what most people picture when you mention fluorescents. They have been common for years in ceiling fixtures in office, retail and other commercial settings. These tubes come in many lengths and diameters, and only work in a fluorescent fixture outfitted with a ballast.

U-Shaped Bulbs

Also sometimes referred to as compact fluorescent bulbs, these u-shaped bulbs are typically designed to work in appliances with external electronic ballasts built in. They’re the midway point between ballast-equipped compact fluorescents and tube-style bulbs. Besides shape, the biggest difference is that twist-in CF bulbs have a built-in ballast which allows them to work in a standard light socket, and these units don’t.

Pros and Cons of Fluorescent Lighting


Fluorescent lights are efficient, producing much more light for a given amount of energy than incandescents. Unlike incandescents, they don’t produce much excess heat, which leads to further energy savings. Though they’re more expensive per bulb than incandescents of similar output, the long-term energy savings more than makes up for the price difference.

Large tube-style fluorescent bulbs give lots of light. While you wouldn’t want such a utilitarian-looking light source in your home, these bulbs work well in workshops, garages and commercial spaces.


The up-front expense of compact fluorescents might be a deterrent, especially when lighting large areas. The mercury inside them can be a problem, too.

If a fluorescent light breaks, the surrounding environment can be contaminated. That’s why broken fluorescents need to be treated as hazardous waste and cleaned up accordingly. This involves clearing everyone from your home, opening doors and windows for several minutes, shutting down all forced-air HVAC systems and then methodically picking up the pieces and placing them in a sealable container.

Also, even if you don’t break one, spent fluorescent bulbs should be disposed of carefully, according to the Environmental Protection Agency (EPA). Unlike incandescents or LEDs, fluorescents need to be taken to a certified recycling facility or, better yet, a hazardous waste disposal facility, because of the mercury they contain.

And finally, fluorescent bulbs don’t work well when it’s cold. They’re brightest at room temperature, but the cooler the room the less light they’ll produce. Anything below freezing and they might not turn on at all.

Is Fluorescent Lighting for You?

It’s up to each consumer to choose the light sources that work best for them, and fluorescent light is still a viable choice in certain situations.

Fluorescent lights are certainly riskier than other types of bulb because of the mercury they contain. They’re also often more troublesome, because of their need for electronic ballasts, poor performance in the cold, and the need to dispose of them in a hazardous waste facility.

That said, they do have some advantages, and a careful user can manage the mercury issue. Despite their disadvantages, they’re still produced and sold in the U.S. and worldwide, and can certainly help you save on your energy bills long-term.