AFCI (Arc Fault Circuit Interrupter) and GFCI (Ground Fault Circuit Interrupter) are two types of breakers. The key difference between the two is that AFCI protects from fire, and GFCI protects from electric shock. Let's look into the characteristics and applications of AFCI and GFCI.

AFCI, or arc-fault circuit interrupter, is the circuit breaker that breaks the circuit upon detecting loose connections in the wiring. They are designed to protect against fires by detecting an unintended electrical arc in a circuit and interrupting the power to prevent ignition. Loose connections are a common reason why electrical fires occur. AFCI can be installed as a circuit breaker in an electrical panel or as a portable device. AFCI protection is required in living residential rooms with high fire risk.

GFCI protects people from electric shock by detecting a circuit's incoming and outgoing current imbalances. When GFCI detects a ground fault, it interrupts the power. A ground fault can occur when you touch a non-insulated part of the electrical device, or when water enters your appliance. GFCI protection is commonly required in moist and damp areas. GFCI can come as a circuit breaker or a receptacle.

AFCI And GFCI Applications Compared

• AFCI protection is required in all living areas of the dwelling units (apartments, houses, and mobile homes) and hotels. This includes new dwelling construction and all updates to existing dwellings. Commercial and industrial spaces do not require AFCI breakers.
• AFCI requirements expand to residential living areas such as bedrooms, rooms, and hallways. This now also includes kitchens and laundry areas (120-volt, single-phase, 10-, 15-, and 20-ampere branch circuits supplying outlets or devices in the kitchen).
• Bathrooms, outdoor spaces, garages, and unfinished basements do not require AFCI protection. 
• The requirements for AFCI are covered by the NEC article 410.12.
• GFCI protection is required for all applications near the water source - bathrooms, kitchen, laundry, outdoor areas, pools, and spas. Damp areas like garages and unfinished basements also require GFCI circuit breakers.
• In previous editions of NEC, only receptacles that serve countertop surfaces needed GFCI protection. However, the 2023 NEC expanded GFCI protection to all kitchen outlets. Unlike AFCI, the requirements for GFCI protection are expanded to commercial and industrial spaces. GFCI is required in any area near sinks.
• Branch circuits and outlets for electric ranges, wall-mounted ovens, counter-mounted cooking units, microwave ovens, and clothes dryers must now include GFCI protection.​ 
• GFCI protection is also mandated for outdoor outlets rated 50 amp or less in garages, for outlets rated not over 150 volts to ground and 50 amp or less in accessory buildings and boathouses, and for all receptacles rated 60 amp or less within 20 feet of a swimming pool wall​.
• Requirements for GFCI are mainly outlined in section 210.8 of NEC.

Where are AFCI and GFCI Used Together?

AFCI and GFCI are used together in the same circuit where protection from electrical fire and electrical shocks is necessary. This includes kitchens and laundry areas.

Cables For AFCI and GFCI

There are no specific requirements for electrical cables based on the fact that they are used together with AFCI or GFCI interrupters. The cables are supposed to fit the environment where they are used. For in-wall indoor residential wiring, the most common cable is NM-B. For garages and unfinished areas where GFCI protection is a must, THWN in conduit is a common choice. For outdoor areas, common cables are UF-B and MC. At NNC, you will find all these common residential cables at excellent prices.