What does a ground fault circuit interrupter (GFCI) do?

A ground fault circuit interrupter (GFCI) is specifically designed to enhance safety by interrupting electrical power when it detects a ground fault. A ground fault occurs when there is an unintended electrical path between the source of current and the ground. This can happen, for instance, when a person accidentally comes into contact with an energized part of a circuit while being grounded.

The GFCI monitors the current flowing through the circuit's hot and neutral wires. If it senses any imbalance, indicating that some current is leaking to the ground, it quickly shuts off the power to prevent shock or electrocution hazards. This quick action is crucial for protecting individuals in wet environments, such as bathrooms or kitchens, where the risk of electric shock is elevated.

Other choices describe different functions that electrical devices may perform, such as protecting against overheating or regulating voltage, but they do not accurately reflect the core operational principle of a GFCI.