Electrician's Licensing Practice Exam

AFCI protection is required in which of the following?

1. All residential branches

2. Only in garages

3. In circuits with plastic boxes

4. In every appliance circuit

The correct answer is: In circuits with plastic boxes

AFCI (Arc Fault Circuit Interrupter) protection is specifically designed to prevent electrical fires caused by arcing faults. The requirement for AFCI protection mainly applies to residential settings, particularly in areas where the risk of fires is elevated due to the presence of certain types of wiring or equipment. The correct choice focuses on circuits with plastic boxes, which is relevant because plastic electrical boxes can increase the potential for overheating or arcing, especially if wires are improperly secured or if there is wear over time. AFCIs are mandated in various locations within the home—such as bedrooms, living rooms, and other areas where circuits are likely to be used for lighting and general purposes. This coverage helps ensure safety by detecting and interrupting the circuit when an arc fault is present. In contrast, the other choices do not accurately reflect current requirements for AFCI placement in electrical installations. While AFCI protection is broadly required in several areas of a residence, it is not limited to just circuits with plastic boxes or restricted only to garages or appliance circuits. Thus, the necessity of using AFCIs in circuits with plastic boxes is an important aspect of electrical safety as outlined in the National Electrical Code.