Expose Six AFCI Myths

AFCI is an advanced circuit breaker that will break the circuit when it detects a dangerous electric arc in the circuit that it protects.

An AFCI can selectively distinguish if it is a harmless arc that is incidental to the normal operation of switches and plugs or a potentially dangerous arc that can occur, such as in a lamp cord with a broken conductor. An AFCI is designed for detecting a wide range of arcing electrical faults that help reduce the electrical system from being an ignition source of a fire.

Although AFCIs were introduced and written into electrical codes in the late 1990s (will discuss the details more later), several myths still surround AFCIs—myths often believed by homeowners, state legislators, building commissions, and even some electricians.

MYTH 1: AFCIs are not so important when it comes to saving lives

“AFCIs are very important safety devices that have been proven many times,” said Ashley Bryant, senior product manager for Siemens.

Arc faults are one of the main causes of residential electrical fires. Through the 1990s, according to the U.S. Consumer Product Safety Commission (CPSC), an average of over 40,000 fires a year were attributed to home electrical wiring, resulting in over 350 deaths and over 1,400 injuries. The CPSC also reported that over 50 percent of these fires could have been prevented when use AFCIs.

In addition, the CPSC reports that electrical fires due to arcing usually occur behind walls, making them more dangerous. That is, these fires can spread undetected more quickly, therefore they can cause more damage than other fires, and they end up being twice as deadly as fires not occurring behind walls, since homeowners tend not be aware of the fires behind walls until it may be too late to escape.

MYTH 2: AFCI manufacturers are driving expanded code requirements for the installation of AFCI

“I find this myth common when I am talking with legislators, but the electrical industry have to understand the reality as well when they are talking with their state senators and building commissions,” said Alan Manche, vice president, external affairs, for Schneider Electric.

Actually the drive for the expanding code requirements are coming from third-party research.

The Consumer Product Safety Commission and studies conducted by UL with regard to thousands of fires occurring in homes in late 1980s and early 1990s drove to figure out the causes of these fires. Arc fault protection has become the solution that was recognized by the CPSC, UL, and others.

MYTH 3: AFCIs are only required by codes in a small number of rooms in residential homes

“The National Electrical Code has been expanding the reach of AFCIs beyond residential homes,” said Jim Phillips, P.E. president of Brainfiller.com.

The first National Electrical Code (NEC) requirement for AFCIs  released in 1999 required them to be installed to protect the circuits feeding bedrooms in new homes. In 2008 and 2014, the NEC was expanded to require AFCIs to be installed on circuits to more and more rooms in homes, now covering virtually all rooms—bedrooms, family rooms, dining rooms, living rooms, sunrooms, kitchens, dens, home offices, hallways, recreation rooms, laundry rooms, and even closets.

In addition, the NEC also began requiring the use of AFCIs in college dormitories from the year 2014. It has also expanded requirements to include hotel/motel rooms that offer permanent provisions for cooking.

MYTH 4: An AFCI only protects what is plugged into the specific defective outlet that triggers the electric arc

“An AFCI actually protects the entire circuit instead of only the specific defective outlet that triggers the electric arc,” said Rich Korthauer, vice president, final distribution business, for Schneider Electric. “Include the electrical panel, the downstream wires that run through the walls, the outlets, the switches, all of the connections to those wires, outlets and switches, and anything that is plugged into any of those outlets and connected to switches on that circuit.”

MYTH 5: A standard circuit breaker will provide just as much protection as an AFCI

People thought the standard breaker would provide as much protection as an AFCI, but actually conventional circuit breakers only respond to overloads and short circuits. They do not protect against arcing conditions that produce erratic and often reduced current.

A standard circuit breaker protects the insulation on a wire from an overload, it is not intended to identify bad arcs on circuits in the home. Of course, a standard circuit breaker is designed to trip and interrupt that condition if you have a dead short.

MYTH 6: Most AFCI “trips” happen because they are “nuisance tripping”

Siemens’ Bryant said he heard this myth a lot. “People think that certain arc fault breakers are defective because they frequently trip. People need to think of these as safety alerts rather than nuisance tripping. The majority of the time, these breakers trip because they are supposed to. They are tripping due to some type of arcing event on the circuit.”

This can be true with “stab” receptacles, where wires are spring-loaded into the backs of the receptacles not wiring around screws, which provide firm connections. In many instances, when homeowners jam plugs into spring-loaded receptacles or pull them out roughly, it usually jostles the receptacles, allowing the wires to come loose, which will cause the arc fault breakers to trip.