Arc fault circuit breakers, also known as AFCI, are a necessary safety standard that is required by the NEC (National Electrical Code). By detecting dangerous arcing in electrical wires and shutting down an electrical system, they play a vital role in protecting the household and its residents.
But to get the most out of them, one must know where are arc fault breakers required.
The NEC dictates that, for any household, AFCIs are required to be installed in all 120-volt, single-phase, 15 and 20 ampere branch circuits, which supply electricity to any room or area of the said household.
I will go over the characteristics of an AFCI as well as where they are required throughout this article.
What is AFCI Protection?
Since 1999, the National Electric Code (NEC) has mandated the use of arc fault circuit interrupters (AFCIs) on certain electrical circuits in homes.
An AFCI outlet can look like an outlet or a breaker (Fig 1). An AFCI outlet can have a button similar to that of a GFCI outlet.
When an electrical current abruptly leaves a wire, this is referred to as an arc fault. When you hear electricity, that static noise is a direct result of an arc being formed somewhere that later flows through the air, causing waves that create sound.
Electrical arcs are dangerous, as they can cause fires. Electrical fires in branch circuit wiring are accounted for nearly one-third of the fires in residences in the USA.
Thus, it is strictly advised to follow the NEC standards when it comes to the use of both AFCI and GFCI protection in any structure with an electrical supply.
Where are Arc Fault Breakers Required?
Arc fault circuit breakers are required for any and all dwelling units or habitable spaces. Dwelling units include any households, flats, dormitories, hotels, motels, and structures of the sort, and are required to be protected by the arc fault circuit breaker standard mandated by the NEC.
Below are some of the key instances where arc fault circuit protection is strictly advised to be used according to NEC.
- Any habitable space within a structure, such as a dorm room, hotel room, bedroom, etc., has an electrical requirement of being protected with arc fault circuits breakers.
- Kitchen and laundry rooms were previously excluded from the list of spaces that required arc fault circuit breaker protection. But due to new National Electrical Code (NEC) standards, they can no longer be excluded from AFCI protection.
- Any 120-volt single-phase power supply, or any 15-ampere and 20-ampere branch circuit, which supplies power to any outlet or a device situated in a habitable space has to be protected by AFCI devices.
- Branch circuit extensions or modifications into any dwelling unit or a habitable space must be subjected to arc fault breaker protection. If a 15 amperes or 20 amperes power supply of 120 volts’ branch circuit wiring is modified, replaced, or extended in any of the living areas, they are required to have AFCI standard integrated into them.
- It is required by most modern refrigerator circuits to be provided with a dedicated 20-ampere circuit. This circuit usually does not require GFCI protection unless the outlet is within 6 feet of a sink or located in a garage or basement, but it generally does require AFCI protection.
Do 220v circuits require GFCI? Or an AFCI? No, circuits that provide more than 20 amps or more than 120 volts can be excluded from AFCI protection. However, it is necessary to use GFCI protection.
But, as mentioned above, AFCI protection is not required everywhere. In the section below, I will list some of the instances where AFCI protection can be left out.
Where Arc Fault Breakers are Not Necessary?
Not every structure or building with an electrical power supply requires AFCI protection. Any space within a structure that does not identify as a habitable space can be exempted from using the AFCI.
Similarly, not every room or location of a household or residence requires the use of an AFCI. Let’s take a look at some of the locations and instances, where an AFCI protection is not req
Similarly, not every room or location of a household or residence requires the use of an AFCI. Let’s take a look at some of the locations and instances, where an AFCI protection is not required
- Any commercial or industrial space does not require the use of an arc fault circuit breaker.
- Bathrooms and toilets are excluded from the list of locations for AFCI protection.
- It is not required to use arc fault circuit breakers for any outlet or device which is situated outside of the residence.
- Circuits that supply voltages less than 120 volts can be left out of AFCI protection.
- There are several “heat and smoke” alarm systems, which are strictly forbidden to be used in conjunction with an AFCI breaker.
- Telephone or TV signal wiring can be excluded from arc fault breaker protection.
- Garages or yards containing any devices or outlets, do not require the installation of an arc fault circuit breaker.
- If no outlets or devices are installed, AFCI protection is not required for extension wires less than 6 feet of length, other than splicing devices. This measurement excludes the conductors contained within an enclosure, cabinet, or junction box.
These are some of the cases where it is not required to use an AFCI protection. Similarly, you might be asking, which location is not required to be GFCI protected? A GFCI is not required in any location where you have used an AFCI.
An AFCI breaker can often replace a GFCI. But, do GFCI breakers replace GFCI outlets? Yes, it is possible to use them interchangeably. But in order to get the most out of them, it is important to know where are GFCI breakers required.
In this article, I thoroughly briefed on the topic of where are arc fault breakers required and why they are necessary. AFCI protection should not only be used because the NEC standard dictates so. Instead, it should be applied due to the concern for one’s safety.
I’ve also added some recommendations to help you lower the financial cost of installing AFCI breakers by stating the areas and sectors where arc fault circuit protection is not necessary.