If your house pre-dates the Lyndon Johnson administration, which began in 1963, chances are that the wiring in your house is one generation out of date. It doesn’t matter if your house is equipped with a newish electrical panel, and all the receptacles are modern three-slot receptacles. The wires are mostly hidden. If your house is pre-Johnson, your walls are probably filled with old two-wire cable. That’s a strong indicator that your receptacles, lights, switches, gizmos and gadgets aren’t grounded.
So what, you say. The lights come on and the TV works. So the wiring is okay, right?
Well, it’s okay in the way that it was okay in the pre-Johnson days to use Mercurochrome on open wounds. Back in the early sixties, when mothers wanted to prevent infection or just make a kid cry, they’d dab Mercurochrome – which contained mercury and probably chromium – directly into the kid’s bloodstream. We had mean bacteria in those days, and folks didn’t think twice about risking a little liver and brain damage in our efforts to wipe them out.
With that digression out of the way, back to wiring. By today’s standards, every outlet, switch and fixture has to have its own ground wire, which runs back to the electrical panel and keeps bad things (shocks, electrocution) from happening.
Let’s say you've got an old metal chandelier and the wiring inside it is frayed. Let’s say that as you reach up to change a bulb, you shake the chandelier just enough to rub the last bit of insulation off the hot wire, and the hot wire touches the metal case. Let’s say you then touch the metal case. As soon as you touch a conductor, you’ll be the ground, and you’ll get shocked. Maybe just a tingle, or maybe a crackling blue flash that puts you into V-fib. The same kind of thing could happen when you touch the metal case on your stove, washer, dryer or toaster.
The risk of electrocution is heightened by the fact that a whole lot of homeowners, handymen and even licensed electricians remove old two-slot outlets and put modern three-slotters in their place, without upgrading the wiring to modern three-wire cable. You homeowners, listen to me: Two-wire circuits need two-slot receptacles. (Yes, they still make two-slot receptacles.) Only three-wire circuits should have three-slot receptacles. I'm amazed I have to explain this.
I have experienced the blue flash personally. I was playing a gig, my guitar was connected to my amp, and my amp was connected to an ungrounded receptacle. When my lips touched the microphone, I saw the blue flash, all of my teeth hurt and I could taste my fillings. I almost shared the fate of Stone The Crows singer Les Harvey, who was electrocuted by microphone way back in 1972.
I’m not saying everybody with a sixties-era house ought to call an electrician and have him rip all the old wiring out of the house. Wiring — even some 50-year-old wiring — can be repaired. Two-wire circuits can be run to ground-fault circuit interrupters (GFCIs), which are built to keep people from getting shocked. Where it’s practical, new three-wire cable can be installed.
I say figure out what kind of wiring you have, and prepare to fix any wiring that needs fixing. You can walk into any decent hardware store and buy a three-light circuit tester for about $10. It will tell you if your receptacles are grounded, and whether the polarity is right.
I know, I know.
Some of you are thinking, “What’s polarity?” Well, correct polarity happens when the hot wire and neutral wire are hooked up to the proper lugs. Reversed polarity happens when some knucklehead wires the circuit(s) up backwards. When polarity is reversed, electrical gizmos will still work and will appear to be okay.
Even so, there are plenty of knuckleheads, including some electricians, who’ll tell you that reversed polarity is not a problem. They are wrong. Reversed polarity is dangerous. If you find receptacles with reversed polarity, get them fixed.
If you're feeling extravagant, buy a tester that will test your ground-fault circuit interrupters (GFCIs).
Those are the receptacles with the TEST buttons on them. They’re supposed to be installed in areas that can get wet. My experience tells me that about half the GFCIs in Nashville are wired wrong.
And now, fair warning: Don’t work on wiring yourself. Hire an experienced electrician. You don’t want the blue flash to be the last thing you see.
Jowers has been writing about renovating old houses, and other things, since 1981. His column appears every Thursday in</i> The City Paper.