The National Lighting Bureau recently issued a press release addressing CFL behavior at end of life. In some cases, the CFL may fail in a manner in which a sizzling sound and some odor or smoke is produced. It’s even possible for the ballast housing to discolor or deform.
Howard Lewis of Visioneering Corporation, National Lighting Bureau chair, asserts the above poses no danger.
“What it really is,” he says, “is a demonstration of the CFL’s remarkable fire-safety design working exactly as it’s supposed to, to protect consumers and keep them safe.”
Snopes.com, the fact-checking Website, states in an article, “[H]ealthy CFL bulbs may emit a bit of smoke and have burnt-looking bases when they die, but that’s as it should be – there’s no fire danger to any of that and, indeed, the bulbs are functioning properly when they act that way.” The Snopes Website also quotes the National Geographic Green Guide as stating CFL bulbs “burn out when the ballast overheats and an electronic component, the Voltage Dependent Resistor (VDR), opens up like a fuse in your home’s fuse box, shutting off the circuit and generating heat and possibly a small amount of smoke. This might sound dangerous, but the VDR is a cut-off switch that prevents any hazards.” In some cases, the ballast’s plastic housing can melt slightly where the glass coil connects to the ballast, the Green Guide states, noting that this “is simply a sign that the heat is escaping as intended in the design of the bulb.”
NEMA provides a technical description of the process here.
Lewis describes the myth is “a vampire rumor: It feeds on fear and refuses to die.”
