Jim Nanni not only consults on testing of compact fluorescent lights at Consumer Reports, he also uses them in his own home. "Used appropriately, CFLs are a great way to save money and energy," Nanni says. "There are some important safety guidelines that consumers should follow in their use." Recently, Nanni captured on camera a rare occurrence that has alarmed some CFL users: a bulb failing dramatically. "It was flashing and making loud noises," he said. "From a distance or behind a shade it might appear like the bulb was on fire, but that wasn't the case. It was the bulb coming to the end of its life."

Underwriters Laboratories investigates products including CFLs for safety. UL listed CFLs are not a fire hazard, according to the organization.

If your CFL has a dramatic end, turn off the power to the bulb, let it cool, and then remove it by grasping from the base and not the glass part of the bulb.

Another concern consumers have is what to do with a broken CFL. "They should follow the guidelines of the Environmental Protection Agency because CFLs do contain mercury," Nanni said.

If a CFL breaks, open the windows and leave the room for at least 15 minutes. On hard floors, do not use a vacuum or broom to clean up the broken bulb. Instead, wear disposable rubber gloves and scoop up the pieces with stiff paper or cardboard. Wipe the area clean with damp paper towels.

To remove a broken CFL from a rug, use sticky tape to pick up the broken pieces and powder. Place all debris and cleaning materials in two sealed plastic bags.

Used CFLs that are not broken should be recycled properly because of the mercury in them. Check with your local sanitation department or go online to www.epa.gov/bulbrecycling for recycling information.

As for CFLs that sometimes smoke, flash, or make sound when they burn out, manufacturers say they are making circuitry changes to prevent the problem in the future.