Ground Fault Interrupters – GFIs – Provide Electrical Safety at Critical Locations in the Home

The funny plugs with the “Test” and “Reset” buttons are mandated by code in many rooms of the house, and they offer a great measure of protection for homeowners and their families

DENVER, CO – Electricity in the home is, of course, an essential component in the infrastructure of modern life. Indeed, if we couldn’t light our world and plug in all of the conveniences of our era, we’d be back, quite literally, in the Dark Ages. Being wired keeps us connected to the world at large and is the bedrock of our comfort, safety and lifestyle.

And while modern electrical systems are safe and reliable, electricity remains a very dangerous commodity that needs to be handled with great care. In fact, electrical codes are ever evolving to insure that safety and reliability.

One of the best examples of this are Ground Fault Circuit Interrupters Circuits (GFCI), or simply GFIs, which were invented in the early 1960s and over the ensuing 50 years have become commonplace, even required, in many locations throughout a home. Here at Allstar Electrical Services our customers frequently ask about “those funny plugs,” the GFIs, so we decided to explain it in laymen’s terms.

The most obvious and common GFI to any homeowner is the GFI receptacle, or plug, that is now required by the National Electrical Code for installation in bathrooms and kitchens where that plug is near a water source. GFIs are also mandated for outdoor plugs, plugs in garages, outlets in crawl spaces and unfinished basements, as well as those on or around wet bars. Also now added to the list of required locations for GFIs are receptacles within six feet of the laundry or any utility sinks. These types of receptacles feature the three-prong, grounded type of plug, where the ground is the tunnel-shaped prong on the bottom in the middle, the neutral is the wide side of the plug, and the “hot” wire is the short side.

In between two places for plugs on the receptacle there will also be two push-buttons labeled “Test” and “Reset.” The manufacturers of these receptacles, as well as electricians, recommend regular, monthly testing of these GFIs to insure they are offering all the protection they were designed to deliver. To “Test,” simply plug a lamp into the receptacle and hit the “test” button; the lamp should immediately turn off. Then hit the “Reset” button and the lamp should immediately turn on. If this doesn’t happen, then the receptacle is wired improperly, or has just given out over time, a common problem that calls for the regular testing.

GFIs come in other configurations, however they are less noticeable to the average homeowner. There are GFIs for installation into a home’s circuit breaker box, and there are portable GFI circuits built into what look like extension cords for use with power tools. Even some appliances, like hair dryers and space heaters, have built-in GFI circuits. All of these, like the receptacles, can and should be tested from time to time, and if something isn’t working – a plug, light, a hairdryer, etc. – hitting all of the pertinent “Reset” buttons will generally resolve the issue. Also, sometimes two or more receptacles will be on the same circuit or line, and if one is not working it might be because the one “upstream” has tripped and needs to be “Reset.”

As stated earlier, electricity can be dangerous and must be treated with great care, but handled properly it is a great asset. GFIs were invented (by Charles Dalziel, a professor of electrical engineering at the University of California, in1961) to protect against the most common form of electrical shock, the ground fault. A ground-fault happens when electricity leaves the wiring connecting an appliance, power tool or a lamp, and then seeks to ground via the shortest route. If that is through a person holding the device, it can be deadly. A GFI measures the difference of power flowing into a device and that flowing out of it, and if it varies by more than 5 milliamps, the device cuts the power – nearly instantaneous. Sometimes a variance exceeding 5 milliamps will be detected right when the appliance is plugged in, and the GFI will trip. Other times the detection won’t happen until a person touches the device, providing a path for grounding; in this case the person may receive a shock, but it will cut off quick enough to avoid serious harm. Ground faults kill about 200 Americans each year – 2 two-thirds of electrocution deaths – so having GFIs in the appropriate places is surely preventing even more electrical mishaps from occurring.

GFIs can be installed by homeowners, but it is critical to understand the proper wiring configuration and perform the task properly. Like everything electrical, Allstar Electrical recommends professional intervention to insure a GFI is installed properly and is operating as it should. We get a lot of calls from customers who discover their “easy” electrical job isn’t working right and they decide to take the safe route and get an electrician.

Since the rules and codes requiring GFIs are ever evolving – kitchens and bathrooms were coded in the 1970s; laundry rooms were added in 2005 – many older homes are technically out of code as it relates to these safety devices. Plus, even though there are widespread admonitions to regularly test these devices, the simple truth is that hardly anyone does it. Like everything else, GFIs are subject to wear and tear and their effectiveness will wane over time. Beyond the “Test” and “Reset” buttons on the GFI device itself, there are also relatively inexpensive GFI testers available at hardware stores and home improvement centers that will aid homeowners in determining the effectiveness of the GFI outlets.

Allstar Electrical Services has been serving the residential and commercial electrical service needs of the greater Denver metro area for more than a decade. We specialize in everything from minor repairs and emergency service, to new-building installation and complete electrical upgrades. We also perform a variety of inspection services. For more information on the complete service capabilities of Allstar Electrical Services visit and call 303-399-7420.

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