Why the Cause May Not Be Electrical
Electrical appliances or wiring are often fire cause scapegoats, simply because they're there. It's unusual to find a burned structure without some electrical wire or device in or near the fire origin.

Ceiling fans, overhead light fixtures, and circuit wiring are common victims of misinterpretation, for a number of reasons:

1) Because fans and light fixtures are normally located near the ceiling, they can be exposed to more direct flames than other items in the room, so it's not uncommon to see them substantially burned by a fire. The more severe damage makes them prime suspects for many investigators.

2) Ceiling fans are usually installed through the protective layer of drywall which forms the ceiling. During installation, a hole is cut in the drywall, which compromises the ceiling's fire-barrier effectiveness.

If a fire occurs in the room below the fan, the flames and heat tend to "vent" through that opening in the drywall, and the fan, of course, becomes significantly burned as a result. A typical post-fire observation is a charred ceiling joist right where the ceiling fan (and the hole in the drywall) was, but to some that becomes evidence that the ceiling fan had "overheated".

3) Electrical wiring is commonly found melted in moderate to severe fire scenes. The melting can occur for several reasons - a] extreme temperature, b] electrical arcing, and c] alloying.

Melted copper wiring due to extreme temperature is potentially a red flag, especially in fires of minor to moderate overall damages. Fire temperatures in most fires are rarely sustained high enough to melt copper wiring. Melted wiring due to arcing does not necessarily mean that the cause was electrical, since arcing can result from the fire. And breakers will often trip due to fire exposure even though no evidence of arcing is readily apparent in the circuits. Alloying is by far the most encountered condition, probably the most misunderstood by fire investigators, and is often confused with melting due to extreme temperature and elecrical arcing.

It's important to be able to distinguish which of these conditions has caused the melting, and why that condition existed at the fire scene.

Page 2