Finding Great Electricians

Finding Great Electricians

How Exactly Do Electrical Wires Ignite And Cause Electrical Fires?

Lucy Garza

An electrical malfunction can cause damage or injury via two main ways; it can either cause a short circuit or trigger an electrical fire. Understanding exactly how an electrical malfunction can cause a fire outbreak can help you prevent such fires. Here are three common ways in which electrical fires start:


Arcing describes an electrical phenomenon where an electrical current passes through a nonconductive medium (commonly air). Due to the high resistance of the nonconductive medium (commonly air), the wayward current generates extremely high temperatures – enough to break down the air and ignite nearby materials. Arcing occurs each time two electrical wires are separated by an extremely thin air gap. For example, arcing may occur when an electrical connection loosens and allows two wires to get closer than they normally are.

Ohmic Heating

Every electrical conductor generates heat when electrical current passes through them; this is known as Ohmic heating. The heat produced is generally proportional to the resistance of the wire; this means an increase in resistance increases the amount of heat produced. An electrical fire occurs when the heat produced becomes too much for the conductor to handle or ignites the environment or materials around the conductor.

There are several ways in which the heat produced can become too much for the conductor and its environment. For one, too much heat can be produced when the resistance of an electrical wire increases beyond a certain point. For example, when an electrical wire is nicked or a connection is loose, the current will only be passing through a small portion of the conductor. The reduced diameter (effective) will lead to increased resistance, possibly leading to a fire outbreak. An electrical wire can also be overwhelmed by heat when it is over insulated and the heat it produces cannot be dissipated away; this is what happens when you run an extension cord under the carpet.

External Heating

Apart from the intrinsic heating of electrical conductors, electrical fires are sometimes traced to external sources of heat. For example, when an insulated electrical conductor is overheated, the insulation breaks down and arcing may occur when the current jumps from the exposed wire to another electrical conductor nearby. This is why it is not advisable to run electrical wires near other sources of heat such as room heaters, fireplaces or engine exhausts.

Hopefully, the knowledge above will help you prevent electrical wires from damaging your household or causing you injuries. If you aren't sure of the state (of safety) of your electrical wiring, consult an electrician to inspect your electrical wiring and help you deal with potential risks.

For more information, talk to a company like DCS Electric.


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Finding Great Electricians

I have never been the kind of person who is overly concerned about my home, but when we started having issues with our electrical systems, it raised a few red flags for me. I was worried about things starting on fire or shocking my kids, so I started looking for a great electrician who could help as soon as possible. I was able to find a local expert who really understood what it meant to do things the right way, and he was really helpful. Within a few days, we were working with him to resolve our electrical problems, and it was nice to see how much of a difference he made.