AFCI protection must be installed for which circuits?

• A. 120-volt, single-phase, 15- and 20-ampere branch circuits that supply outlets or devices in most every room of a dwelling unit
• B. All 120-volt circuits
• C. Only kitchens require AFCI protection
• D. Only outdoor outlets

Answer: (A)

AFCI protection targets the circuits that feed outlets or devices in living areas to reduce the risk of fires from arc faults. The rule applies to 120-volt, single-phase, 15- and 20-amp branch circuits that supply outlets or devices in most rooms of a dwelling unit. That means these living-space circuits must have AFCI protection, typically either with an AFCI breaker at the panel or an equivalent protection device.

Why this fits best: it specifies the voltage, phase, and amperage range that commonly supply outlets or devices in living areas and covers most rooms in a dwelling, which is exactly what the AFCI requirement is meant to protect. It’s not all 120-volt circuits (some circuits that don’t feed outlets or are dedicated for specific loads may be treated differently), and it’s not limited to only kitchens or only outdoor outlets.