The Ground Fault Circuit Interrupter
I was recently in Roseville, Minnesota doing a walk through with the client for their Home Inspection. This home was built prior to 1971, before any requirements for GFCI's were in place and no modifications were made to the electric, meaning no GFCI's.
When I suggest a GFCI, its a safety concern, you are not required to put them in, but it is highly recommended.
What is a GFCI
A Ground Fault Circuit Interrupter is a device that can help prevent electrical shock. When functioning properly it interrupts the flow of electricity when it senses a ground-fault. More commonly installed at the receptacle, they are sometimes installed as a breaker in the electrical panel. They work by monitoring the flow of current between the ungrounded (hot) and grounded (neutral) conductor. The amount of current going to an electrical device should balance whats returning from the device. Should the current flowing through both conductors vary by a very small amount (around 5 milliamps) the GFCI will interrupt the current, stopping the flow of electricity. If it does vary by an excessive amount, it could mean that electricity is diverting from its intended path, when this happens it will always seek a path to ground, and this path could be you.
GFCI requirements have grown over the years and since 1993 any receptacle updated in an area presently requiring a GFCI receptacle must be replaced with one.
A Short History of GFCI Receptacle Requirements
1971 Receptacles within 15 feet of pool walls
1971 All equipment used with storable swimming pools
1973 All outdoor receptacles
1974 Construction Sites
1975 Bathrooms, 120-volt pool lights, and fountain equipment
1978 Garages, spas, and hydromassage tubs
1978 Outdoor receptacles above 6ft.6in. grade access exempted
1984 Replacement of non-grounding receptacles with no grounding conductor allowed
1984 Pool cover motors
1984 Distance of GFCI protection extended to 20 feet from pool walls
1987 Unfinished basements
1987 Kitchen countertop receptacles within 6 feet of sink
1990 Crawlspaces (with exception for sump pumps or other dedicated equip.)
1993 Wet bar countertops within 6 feet of sink
1993 Any receptacle replaced in an area presently requiring GFCI
1996 All kitchen counters – not just those within 6 feet of sink
1996 All exterior receptacles except dedicated de-icing tape receptacle
1996 Unfinished accessory buildings at or below grade
1999 Exemption for dedicated equipment in crawlspace removed
The good news is these are relatively easy and inexpensive to install by a qualified professional. Often times the savvy home owner can replace a standard receptacle with a GFCI in a few minutes. One of my childhood favorite shows, This old House covers doing so pretty well.
- Never paint a GFCI. I have come across hundreds of painted GFCI's that fail to trip as a result.
- Test regularly using the test button. I often recommend monthly, making sure they properly trip, allowing you to reset it. If it fails to trip, replace immediately. When performing a Home Inspection, I test using both the test button on the receptacle, as well as my GFCI tester.
Please let me know if you have any questions. I'd be happy to update this post with information you think would be beneficial to the newer home owner.