Proper grounding of your electrical system is essential to your safety. Electricity always follows the path of least resistance, and that path could be you whenever an appliance or another electrical component is not grounded.
Grounding directs electrical energy into the earth by providing a conductor that is less resistant than you are. This is accomplished by attaching one end of the wire to the frame of an appliance and fastening the other end to a coldwater pipe. Most plastic-coated electrical cable contains a bare wire, which carries the grounded connection to every electrical box, receptacle, and appliance in your home. You can usually tell whether your electrical system is grounded by checking the receptacles. If you have the kind that accepts plugs with two blades and one prong, your system should have three wires, one of which is a grounding wire. The prong carries the safety ground to the metal frame of any appliance that has a three-wire plug and cord.
An appliance's metal frame can pose a safety hazard to you and your family. If a power cord's insulation wears away just at the point where the cord enters the metal frame, contact between the metal current conductor and the metal frame could make the whole appliance alive with electricity. Touching a charged metal frame of the appliance while simultaneously touching a water faucet or a radiator will make the current surge through you.
There are other places throughout the electrical system where conductor/metal contact is a distinct possibility and a safety hazard. Be sure to inspect, maintain, and make repairs wherever wires enter a metal pipe (conduit), where the cord enters a lamp or lamp socket, and where in-wall cable enters an electrical box. Surfaces at these points must be free of burrs that could chafe the wire and damage its insulation. Washers and grommets protect the wire at these various points of entry. However, the best thing you can do to ensure a safe electrical system is to make sure the whole system is grounded and the ground circuit is electrically continuous, without any breaks.
The bottom line is that you need to make electrical safety a top priority whenever you do home repairs. Furthermore, don't hesitate to call on a professional electrician when necessary.
On the next page, we'll take a look at how to restore a circuit and what steps you should take in a power outage.