Activity: You’re Grounded!
A ground fault circuit interrupter (GFCI) is a
safety device that monitors the flow of current to and from an appliance.
If there’s more current flowing to an appliance than coming
back, it means that some is traveling to the ground—perhaps
through you—and the GFCI will quickly cut power. You can still
get a shock in the time it takes the GFCI to interrupt the ground
fault, but you are less likely to be seriously injured.
GFCIs can be found in newer outlets and service panels and embedded
in the cords of some appliances. Take a few minutes to find out
where GFCIs are located in your home or school. Think about why
they are located where they are.
Search your home or school for GFCIs. On a sheet of paper,
make a note of where they’re located and if any appliances
have them built into the cord. (Don’t confuse a GFCI with
an adapter, which reduces the voltage of electricity entering
the appliance. A GFCI will have test/reset buttons. An adapter
What conclusions can you draw about where GFCIs are placed?
Based on your conclusions, are there any outlets that probably
should have a GFCI but don’t? Why do some appliances have
a GFCI in their cord, but others don’t?
- GFCIs should be tested monthly. With an adult, test the GFCIs
in your home or classroom using these steps:
Plug in a lamp or radio in the GFCI-protected outlet and turn
it on. (For appliances that have a GFCI built into the cord,
plug in the appliance and turn it on.)
Press the “test” button on the GFCI. The test
button works by allowing a small amount of current to flow to
the ground wire, simulating a dangerous ground fault in the
The “reset” button should pop out and the appliance
should turn off.
If the appliance doesn’t turn off, the GFCI is not working
properly and will not protect you from getting shocked.
Ask your family or school custodian to have a licensed electrician
replace bad GFCI outlets and to replace appliances with bad
- When you’re done testing each GFCI, press the reset button
to restore power.
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