Compact fluorescent lights smoke when they die

WASHINGTON - Poof! A puff of smoke. No, that's not magic. It means your compact fluorescent light bulb just burned out.

John Drengenberg, an engineer and consumer affairs manager at Underwriters Laboratories, says consumers have reported concerns about smoking bulbs.

He says after testing various types of CFLs, UL found the smoking is normal when the bulb dies.

"In an older style bulb, the incandescent type, when the bulb burns out we're all accustomed to the bright flash, and we unscrew the bulb and put in a new one. But that bright flash is contained inside the glass part of the bulb.

"With the new compact fluorescent bulbs, that little flash or that burning out situation happens in the base and sometimes consumers see smoke and smell a little smoke and even see discoloration on the base but this is a normal end of life scenario."

CFLs characteristically are energy efficient and have long life spans; however, they expire sooner than expected under certain conditions: the light fixtures they are in and the way they are used.

"If you screw them into sockets that are pointed down or pointed up, makes a difference in the lamp life because the heat sometimes from the lamp actually rises above the base where all the electronic components are located. So if you're screwing it into a fixture where the lamp is pointing down, it probably won't last quite as long as if you were screwing it into a fixture where the lamp was pointing up."

Like downward pointing sockets, enclosed light fixtures limit the life spans of CFLs since the heat generated from the bulb cannot escape and eventually affects the bulb's base.

Drengenberg warns that people who use CFLs in dimmer lights can expect the bulb to burn out quickly.

CFLs also differ from traditional bulbs in their disposal. Because they contain mercury, compact fluorescents need to be disposed at a waste management facility or a local recycling program.

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