A circline fluorescent light bulb is part of the fluorescent family. What makes this light bulb stand apart from the rest is the shape. Instead of a linear tube or a U-shape, circline fluorescent light bulbs are in the shape of a circle.
Circline fluorescent light bulb shapes and sizes
Circline fluorescent light bulbs come in three different sizes, and like the rest of the fluorescents, the size depends on the diameter of the tube itself (not to be confused with the total diameter of the circline bulb).
A T5 circline fluorescent is 5/8” in diameter. Like a T5 linear fluorescent, a T5 fluorescent circline is the brightest and most energy efficient option even though they are the smallest in diameter.
A T6 circline fluorescent is .75” in diameter. These are not as common, but we do have some ready to purchase.
The largest in diameter, a T9 circline fluorescent is 1.125”.
All of the circline fluorescent light bulbs are also available in total diameters from 6” to 16”. The wattage of the bulb correlates to the total diameter. A 6” circline fluorescent is 20 watts, an 8” is 22 watts, a 12” is 32 watts, and a 16” circline fluorescent is 40 watts.
You might also see fluorescent circlines with two circular tubes. You can use these in places where you need a higher light output, or lumens, in a small amount of space.
Another specification that might change which light bulb you need is the base. Circline fluorescents have two different bases: 2GX13 or G10Q. They both have 4-pin bases.
Where to use fluorescent circline light bulbs
Because of their shape, you are probably not surprised that fluorescent circline light bulbs are most commonly used in round overhead fixtures.
Hotels often use fluorescent circlines in hallways or common areas like lobbies. You might also find them in some multifamily buildings or other residential settings.
Do fluorescent circline light bulbs require a ballast?
All fluorescent light bulbs operate off a ballast, so it’s important to check compatibility before you buy the product. A ballast regulates and stabilizes the light output from the fluorescent circline light bulbs.
Circline fluorescent light bulbs run off two different types of ballasts: magnetic and electronic. But unlike other fluorescent ballasts, circline light bulbs need their own specific type of ballast. If you need to look at your options or shop for a new fluorescent circline ballast, click here.
Recycling fluorescent circline tubes
Since fluorescent circline tubes are part of the fluorescent family and contain mercury, you need to recycle them just like other fluorescent light bulbs. Fluorescent light bulbs contain mercury. When mercury ends up in the landfill, it can be harmful to the environment. Regency Lighting offers recycling boxes ready to purchase.
Questions about fluorescent circline tubes
If you have any questions about fluorescent circline light bulbs, or you need help finding the right light bulbs, do not hesitate to contact us. As a national lighting distributor since 1983, Regency Lighting has seven sales and distribution locations to meet your lighting needs. Click here to send us a message, call us, or use the chat in the bottom right corner of your screen. Our lighting specialists are always here to help.