Editing Incandescent light bulb (section)

===Safety===
The filament in a tungsten light bulb is not easy to break when the bulb is cold, but filaments are more vulnerable when they are hot because the incandescent metal is less rigid. An impact on the outside of the bulb may cause the filament to break or experience a surge in [[electric current]] that causes part of it to melt or vaporize.
In most modern incandescent bulbs, part of the wire inside the bulb acts like a [[fuse (electrical)|fuse]]: if a broken filament produces an [[electrical short]] inside the bulb, the fusible section of wire will melt and cut the current off to prevent damage to the supply lines.

A hot glass bulb may fracture on contact with cold objects. When the glass envelope breaks, the bulb [[implosion (mechanical process)|implodes]], exposing the filament to ambient air. The air then usually destroys the hot filament through [[oxidation]].