Ground fault circuit interrupters (or GFCIs) are electrical safety devices that trip electrical circuits when they detect ground faults or leakage currents. Since their incorporation into the National Electrical Code in 1971, GFCIs have saved thousands of lives and reduced home electrocutions by 50%!
Undoubtedly, GFCIs have played a key role in reducing electrocutions and greater use of GFCIs would help mitigate thousands of electrical burns and shock injuries that continue to occur in homes every year.
In addition to the lives saved, GFCIs also prevent electrical fires and millions of dollars in property damage.
- GFCI’s shut off electric power in the event of a ground fault within 1/40 of a second.
- 26% of respondents who tested GFCI receptacles discovered one that was not working.
- In the United States, arcing faults cause about 30,000 home fires each year, resulting in hundreds of deaths and injuries and more than $862 million in property damage.
Please find a few FAQs to help understand how GFCIs help protect your home and family.
What is a ground fault circuit interrupter?
A ground fault circuit interrupter (GFCI) is a device that shuts off an electric power circuit when it detects that current is flowing along an unintended path, such as through water or a person.
Ground fault protection is integrated into GFCI receptacles and GFCI circuit breakers for installation into an electrical system. Ground fault protection is particularly important for circuit outlets in areas where electrical equipment is near water (such as bathroom or kitchen sinks).
But, what is a ground fault?
A ground fault is an unintentional electrical path between a power source and a grounded surface. Ground faults most often occur when equipment is damaged or defective, such that live electrical parts are no longer adequately protected from unintended contact.
Many home electrocutions, burns and shocks occur when a ground fault is not in place. If your body provides a path to the ground for this current, you could be burned, severely shocked or electrocuted.
How Does a GFCI Protect My Home and Family?
The GFCI is designed to protect people from severe or fatal electric shocks.
A GFCI constantly monitors the current flowing through a circuit by measuring the current flowing into the circuit compared to the returning current.
Additionally, because a GFCI detects ground faults, it can also prevent some electrical fires and reduce the severity of other fires by interrupting the flow of electric current.
A person who becomes part of a path for leakage current will be severely shocked or electrocuted. These outlets prevent deadly shock by quickly shutting off power to the circuit if the electricity flowing into the circuit differs by even a slight amount from that returning.
This protects your family.
How Does a GFCI Outlet Work?
In properly working appliances, the electricity flows from from hot to neutral and the GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit to stop the flow of electricity.
What does this mean?
In the US, most homes have 120-volt outlets, where there are two vertical slots (with the left slot slightly larger than the right slot) and then a round hole centered below them.
- The left slot is called “neutral”
- The right slot is called “hot”
- The center hole is “ground”
For example, if you are outside with a power drill completing a project as it starts raining, you are standing on the ground. Since the drill is wet, there is a path from the hot wire inside the drill through you to ground.
If electricity flows from hot to ground through you, it could be fatal.
The GFCI can sense the current flowing through you because not all of the current is flowing from hot to neutral as it expects – some of it is flowing through you to ground! As soon as the GFCI senses that, it trips the circuit and cuts off the electricity.
How Do Homeowners Test GFCIs?
The ESFI provides a simple video detailing GFCI testing instructions.
The best way to test a GFCI is based on the manufacturer’s instructions. However, if the instructions are not readily available, here is a commonly accepted procedure, which are outlined in the testing video.
- Plug a lamp into the outlet and turn the lamp on.
- Press the GFCI’s test button.
Did the light go out? If not, the GFCI is not working or has not been correctly installed and you should contact a qualified electrician to correct the wiring and/or replace the defective GFCI.
If the light went out, press the reset button.
Did the light come back on? If not, replace the GFCI. If the light came back on, then the GFCI is working appropriately.
Homeowners should test all GFCIs every month.
Where Should Homeowners Install GFCIs?
Everywhere that is applicable. A GFCI should be used in any indoor or outdoor area where water may come into contact with electrical products.
GFCIs are most frequently used in wet locations, construction sites or other high-risk areas to interrupt the flow of electricity within as little as 1/40 of a second to prevent electrocution.
For reference, the National Electrical Code notes the GFCI requirements (and effective date):
- Outdoors (since 1973)
- Bathrooms (since 1975)
- Garages (since 1978)
- Kitchens (since 1987)
- Crawl spaces & unfinished basements (since 1990)
- Wet bar sinks (since 1993)
- Laundry and utility sinks (since 2005)
It is advisable to consider portable GFCI protection whenever operating electrically-powered garden equipment (mower, hedge trimmer, edger, etc.) or with electric tools (drills, saws, sanders, etc.) for do-it-yourself work in and around the house.
Is a GFCI Installation a DIY Project?
No. The ESFI advises that GFCIs should only be installed by a licensed, qualified electrician.
However, portable GFCIs require no tools to install and provide flexibility in using receptacles that are not GFCI-protected.
Do you have any questions? SolvIt is ready to answer any questions or help install any GFCIs, so please feel free to contact SolvIt today.