What is a requirement for AFCIs in new residential construction according to the NEC?

The National Electrical Code (NEC) mandates specific safety measures for residential construction to help prevent electrical fires, and one of the key safety devices introduced is the Arc-Fault Circuit Interrupter (AFCI). According to the NEC, AFCIs are fundamentally required for all 120-volt, single-phase, 15- and 20-ampere branch circuits that supply outlets in dwelling units. This requirement helps protect against arc faults, which are a leading cause of electrical fires due to damaged or frayed wires.

AFCIs work by monitoring the electrical currents and detecting potentially hazardous arc faults, which can occur due to various reasons such as damaged wiring, loose connections, or other electrical faults. By cutting off the circuit when an arc is detected, AFCIs provide vital protection, enhancing the safety of the residential electrical system.

In contrast, the other options do not align with the NEC's requirements as clearly stipulated. For example, restricting AFCIs to only external circuits neglects their essential protective function throughout the dwelling. Likewise, suggesting they are optional or only necessary for specific areas such as kitchens contradicts the widespread requirement set for all applicable circuits within residential units as defined by the NEC. Thus, the understanding that AFCIs must be used broadly