Q&A: Can CFLs interfere with electronic equipment?

A friend believes that compact fluorescent lightbulbs in her den cause her TV to change channels on its own. Is there a poltergeist in her house, or can CFLs really cause interference?

Your friend is probably not sharing her home with any mischievous spirits. Most modern TVs, radios, cell phones, and remote controls rely on infrared light to send signals. It’s not common, but some electronic devices mistakenly interpret the infrared light emitted by CFLs as a signal, causing them to temporarily go kerflooey.

Energy Star-qualified CFLs likely won’t cause this interference, one reason why we recommend that you use only Energy Star CFLs. As we reported in “New twists in savings,” these bulbs also meet tough standards for start-up and warm-up times, brightness, color, bulb life, and energy use, and they can’t hum or buzz. If a particular model of CFL does cause interference, a warning must appear on its packaging.

Our advice is that your friend not use CFLs in fixtures near her TVs, radios, remote controls, or cell phones. If interference occurs, she should move the CFLs away from the electronic equipment or plug the light fixture and the electronic device in different outlets.

Also be aware that some timers can shorten the life span of CFLs. “While CFLs can be used with mechanical timers, electronic or digital timers may cause interference with the electronic ballast, and can adversely affect product performance. Typically, CFLs used on electronic or digital timers will fail far before their rated lifetime,” say the folks behind the Energy Star program.—Kimberly Janeway