Helpful Hints About GFCIs

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Ground Fault Circuit Interrupters (GFCIs) are safety devices that provide protection against electric shock and electrocution when a ground fault occurs. Often the result of damaged appliance cords or water getting into the product, a ground fault occurs when the electrical current in a product strays outside of the path where it should flow. If a person is handling the device at that time the current may use that person as the ground, and injury may occur. Unlike a standard outlet, a GFCI measures outgoing and returning electrical current and shuts off or trips when it senses an imbalance or surge.

The advantage of using GFCIs is that they detect even those amounts of electricity too small for a fuse or circuit breaker to activate and shut off the circuit. This happens within a second (or less) to prevent a person from being shocked. If every home in the United States used GFCIs, experts say, more than two-thirds of all residential electrocutions could be prevented.

Building codes now require the use of GFCIs on electrical outlets within six feet of water sources in bathrooms, kitchens, garages, and exterior. Found at most home centers or hardware stores, they are typically priced at $7.00 and up and are available at both 15 amp. and 20 amp. ratings. If installed as the first outlet in a circuit, a GFCI will protect all of the outlets wired downstream from it. When replacing an outdoor outlet, make sure that it has a weatherproof cover.

Once a GFCI is installed, it must be checked monthly to determine that it is operating properly. Units can be checked by pressing the "TEST" button; the GFCI should disconnect the power to that outlet. Pressing the "RESET" button reconnects the power. If the GFCI does not disconnect the power to that outlet, place a call to a qualified certified electrician.

National Electrical Code Required Locations for GFCI Outlets