TL;DR
A GFCI, or ground-fault circuit interrupter, is a protective device that compares current flowing out on the hot conductor with current returning on the neutral and opens the circuit within a fraction of a second when the difference exceeds about 5 milliamps, the level that signals current leaking through a person. The NEC requires this protection in bathrooms, kitchens, garages, outdoors, and other wet locations.
What it means
A GFCI, or ground-fault circuit interrupter, is a protective device that compares current flowing out on the hot conductor with current returning on the neutral and opens the circuit within a fraction of a second when the difference exceeds about 5 milliamps, the level that signals current leaking through a person. The NEC requires this protection in bathrooms, kitchens, garages, outdoors, and other wet locations. It comes as a receptacle, a breaker, or a portable adapter, each with test and reset buttons that should be exercised monthly.
Where it sits in the glossary
GFCI is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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