If you’ve experienced any electrical problem, you probably assume it’s cause for worry right away. In the case of a black light bulb, this may not be true, but it’s better to be safe rather than sorry. If a lightbulb turns black, this is most likely a sign that your bulb needs to be replaced.
Why CFL Light Bulbs Turn Black
Compact fluorescent light bulbs may emit a bit of smoke when they burn out, but they are designed to do this. Most CFL bulbs burn out when the ballast overheats, and the electronic component inside, the Voltage Dependent Resistor (VDR), opens. This is similar to your fuse box shutting off the circuit in your home. In both cases, a small amount of heat is present, and possibly some smoke.
We realize this sounds dangerous, but the VDR functions as a cut-off switch that will prevent any serious hazards. Just be sure to change the bulb ASAP!
Are CFLs a Fire Hazard?
Despite what most people think, these energy-efficient bulbs are not a fire hazard. However, any electrical device or appliance can malfunction if it’s not used correctly. Be sure to use your light bulbs the right way, and ensure that they’re connected to the fixture. Other signs of a misused bulb include using a bulb that has the wrong wattage.