Safety
AROUND YOUR HOME

Be safe — install outlets correctly

Jim Nevel

If your house was built in the last 20 years or so, chances are that your electrical outlets, often called receptacles or receptacle outlets, have three holes for you to plug lights or appliances into.

Earlier homes had two-hole outlets. Generally speaking, the three-hole outlets are safer than the earlier ones, and the National Electrical Code (NEC), requires their installation in new construction, and when replacing old ones.

The third hole, the round one, was added years ago as a safety feature, and gradually found its way into many homes. But it's there for a reason. It leads to a ground that will help prevent electric shocks or fires.

If you'll look carefully at a three-prong plug, you'll note that two of the prongs are flat, while the other is round or U-shaped. Look even more carefully, and you'll see that it's also a little longer than the others are. That's a safety factor, too.

NEC has tried to engineer plugs and receptacles for maximum safety to prevent any injury when a plug is unplugged carelessly. Since the third prong is a little longer than the two flat ones, it ensures that the last electrical connection to be opened in the circuit will be the ground connection. This will always be true, if the plug is pulled straight out of the outlet.

Unfortunately, most are not. Ergonomic studies have shown that those lower outlets along the walls make it difficult to pull the plug straight out, without kneeling on the floor beside the receptacle. Rather than doing that, most people pull outward and upward as they unplug cords.

Engineers have worked hard to figure how to build things so people will be safe, even if they don't unplug correctly. With that in mind, it makes more sense to have your electrician wire your receptacles so that the round hole is above the slots for the flat prongs. With the receptacle in that position, pulling outward and upward ensures that the longest prong is the last to break contact. That's the way it should be.

Outlets placed at the countertop level are different. Students of such things note that people tend to pull downward and outward when they're unplugging cords from countertop outlets. With that in mind, you need to ask your electrician to wire those outlets with the round hole below the slots for the flat prongs.

NEC doesn't actually specify how outlets should be mounted, but it does require that safe wiring practices be followed.

But what if your home has two-prong receptacles? Many older homes do. Two-prong outlets have no safety ground electrode and no ground wire. NEC no longer permits installing two-prong receptacles in homes.

There are several ways to address this problem. If the wiring is done through conduit or BX cable and the conduit is continuous back to the service panel, you can connect the new receptacle to the metal receptacle box.

If there is a metallic cold water pipe going nearby, and you're sure it's electrically continuous to the main house ground point, you can run a conductor to it from the third ground wire terminal connection. Another wiring safety procedure would be to run a ground wire back to the service panel.

The easiest solution might be to install a ground-fault circuit interrupter (GFCI) receptacle. The ground lug should not be connected to anything, but the GFCI protection itself will serve as the protection. The NEC requires those three-prong receptacles without a ground that are protected by GFCI must be labeled as such.

Jim Nevel, manager of regulatory compliance for the Association of Illinois Electric Cooperatives.

14 ILLINOIS COUNTRY LIVING • MARCH 2001