It came over the radio as a blue arc flame coming from an electrical outlet in the living room. We arrived to no fire, but a scary scene. The bright white walls were scorched and scarred black under the front window - the focal point of the living room. We all have them. The electrical outlet that’s just a tick loose. It pushes when you put a plug into it, and pulls out when you disconnect. You don’t think much of it, do you? I have to admit that I’ve neglected some of my own, but I checked them all as soon as I got home today.
The homeowner was lucky. First of all she had no furniture in front of the outlet. Secondly, she didn’t try to pull the plug back out when she plugged the stereo in and it flashed. When I was finished with the investigation, it was obvious what caused the short circuit that could have burnt her house down. These are my favorite types of investigations. There’s actually enough material left to make a good determination. The circuit in question also fed several other outlets, including an outside outlet. Today that would have been a ground fault protected circuit, but that’s a blog for another day. The hot wire was strip connected in series into the outlet, so the outlet being loose caused a serious problem. Every time the owner or an occupant plugged in something, the outlet moved, the wire rocked in it’s contact channel and the screw securing the wire to the outlet loosened a micron. This happened over about 25 years until today the outlet rocked against the steel electrical box inside the wall and it shorted. The outlet blew off it’s bottom end and threw a blue flame about a foot and a half into the room. The owner was terrified, but she appparently wasn’t terrified enough not to reset the breaker and try to give the outlet power again. Don’t ask me why she would do such a thing, but that’s what happened. Lo and behold, another big arc occurred before the breaker once again tripped out.
The fire engine company arrived and determined with the thermal imaging camera that nothing had caught fire inside the wall, then the guys turned the scene over to me for investigation. The burnt out outlet told me a couple of things that I want to share with you.
First, never ever restore power to a component that has arced without replacing the failed piece. It’s not like a headache. Problems with electrical parts do not fix themselves in my experience, and arc flashing is fatal to whatever took the high energy electrical hit. Have your electrician go over your system in it’s entirety before restoring power to any section that suffered a failure of any kind.
Secondly, if you have any electrical outlets or switches that are loose, broken or seem to intermittently cause problems, get them fixed now. Don’t wait to let the lightning out of the clouds. All it takes is the right (or wrong) move to begin an arc flash incident and serious injury or property damage can occur. The same goes for loose boxes, broken switch and outlet plates and non-working GFI outlets.
Electrical wiring and contacts don’t like to come loose. One thing that always comes back to me whenever I talk about electricity is that you can compare it to water, except that you can see the water. Electrical wires are the pipes that electrical current passes through. You wouldn’t leave a leaking faucet or loose toilet go for very long. Think the same way about your electrical system.
Finally, if you find loose cover plates on your electrical outlets and you feel comfortable doing a little work on your own, get that screwdriver out and get to work. Just a little twist to tighten up those plates could make all the difference in the world.
