How do CFL bulbs fail?
CFLs occasionally burn out, but more often will continue to operate, gradually producing less light as it ages. At some point you’ll want to replace it for brighter light. ENERGY STAR qualified CFLs must produce at least 80 percent of its rated light output at 40 percent of its rated life. Only rarely do CFLs fail more dramatically, with a combination of flickering, sputtering, a puff of smoke or melted plastic. ENERGY STAR qualified bulbs must use plastics that do not support combustion, and most are protected by internal fuses. If your bulb fails as describes above, turn off the power to the fixture as quickly as possible.
