GFCI and AFCI: Test the Outlets and Breakers That Keep You From Getting Shocked

Two small safety devices protect most modern homes from electrical shocks and fires, and they both have a test button that almost nobody presses. It takes about a minute to check each one, and the Electrical Safety Foundation International (ESFI) recommends doing it monthly.

01What they do

GFCI (ground-fault circuit interrupter) protects people. It watches for electricity leaking out of the circuit, like through a person standing on a wet floor, and cuts the power in a fraction of a second. ESFI says GFCIs could prevent a large share of the home electrocutions that happen every year.

AFCI (arc-fault circuit interrupter) protects the house. It watches for arcing, the sparking that happens with damaged cords, loose connections, or a nail through a wire, and shuts off the circuit before it can start a fire.

02Where you should have GFCIs

Anywhere water and electricity meet: kitchens (countertop outlets), bathrooms, laundry rooms, garages, unfinished basements, crawl spaces, outdoor outlets, and near sinks and wet bars. A GFCI can be the outlet itself (with TEST and RESET buttons) or a breaker in the panel that protects the whole circuit. One GFCI outlet can also protect other regular outlets downstream from it.

Older homes often have none, or only a few. Adding them is one of the cheapest safety upgrades there is.

03Where you'll find AFCIs

Usually as breakers in your electrical panel, with a TEST button on the breaker. Newer homes have them on most living-area circuits: bedrooms, living rooms, hallways and more. Older homes may not have any.

04How to test a GFCI outlet

1. Plug a nightlight or lamp into the outlet and turn it on.
2. Press TEST. The light should go out (you may hear a click).
3. Press RESET. The light should come back on.

If the light doesn't go out, the GFCI isn't protecting you. If it won't reset, the device may be bad, or there may be a problem in the circuit. Either way, get it replaced.

Test the outlets downstream too. If you trip a GFCI and another outlet down the wall also goes dead, that one's protected by it. That's how you find the mystery GFCI in the garage that's been killing the outdoor outlet.

05How to test an AFCI or GFCI breaker

1. Open the panel door (not the cover; just the door).
2. Press the TEST button on the breaker. It should trip to the off or middle position.
3. Flip it fully off, then back on.

This turns off everything on that circuit, so save it for a time when nobody's on the computer.

06When one trips by itself

• A GFCI that trips when it rains, or every time an appliance runs, usually means moisture in an outdoor outlet or a failing appliance. Check outdoor covers and cords.
• An AFCI that trips repeatedly may be telling you about a damaged cord, a bad connection, or a loose wire somewhere. Don't keep resetting it. Have an electrician find out why.
• Any outlet or breaker that's hot, buzzing, scorched or smells like burning: turn it off and call an electrician now.

07Before winter

Space heaters, holiday lights and outdoor decorations all put extra load on circuits. Test your GFCIs and AFCIs before the decorations go up, and check our electrical panel red flags while you're at the panel.

Sources (2)

ESFI: Ground Fault Circuit Interrupters (GFCI) · ESFI: How to Test an AFCI

Related: A Comprehensive Guide to DIY Home Inspection: Safeguarding Your Home Inside and Out