What is the purpose of GFCI outlets in residential installations?

• A. To enhance energy efficiency of the circuit
• B. To protect against electrical shock by shutting off power when detecting ground faults
• C. To regulate the voltage supplied to appliances
• D. To provide additional power to high-demand appliances

Answer: (B)

The purpose of GFCI (Ground Fault Circuit Interrupter) outlets in residential installations is to protect against electrical shock by monitoring the electrical current flowing through the circuit. When a ground fault is detected—meaning there is an imbalance between the outgoing and incoming current, which could occur if the current is flowing through an unintended path such as water or a person's body—the GFCI outlet responds by shutting off power to the circuit almost instantaneously. This rapid response greatly reduces the risk of serious injury or fatality due to electric shock, making GFCI outlets crucial for safety in wet or damp areas such as kitchens, bathrooms, and outdoor locations.

Enhancing energy efficiency, regulating voltage, or providing additional power to appliances are not functions of GFCI outlets. Energy efficiency focuses on reducing the amount of energy used, while voltage regulation pertains to maintaining a specific voltage level for appliances, neither of which is a feature or purpose of GFCI technology.