What is the primary purpose of a ground fault circuit interrupter (GFCI)?

The primary purpose of a ground fault circuit interrupter (GFCI) is to protect against electric shock by interrupting the circuit when it detects an imbalance in current. A GFCI monitors the flow of electricity through a circuit, comparing the amount of current flowing to the electrical device with the amount of current returning. If there is a difference, indicating that electricity is escaping the intended path—such as flowing through a person who may be in contact with the electrical circuit—the GFCI will quickly disconnect the power. This rapid response reduces the risk of serious injury or fatal electric shock.

Understanding the function of a GFCI is crucial in environments where there is a higher risk of electric shock, such as bathrooms and kitchens, where water and electricity may come into contact. The device is an essential safety measure mandated by electrical codes in specific settings to enhance protection for users.