Copy of AFCIs on the Brink of a Home Invasion

If proposal #2-142 of the National Electric Code (NEC) passes, it will require combination-type arc-fault circuit interrupter (AFCI) protection for all 15A and 20A, single-phase, 120V circuits in dwelling units by Jan. 1, 2008. The combination-type AFCI combines the protection of branch/feeder circuits with increased sensitivity as well as added protection for cord-and-plug-connected equipment. The

If proposal #2-142 of the National Electric Code (NEC) passes, it will require combination-type arc-fault circuit interrupter (AFCI) protection for all 15A and 20A, single-phase, 120V circuits in dwelling units by Jan. 1, 2008. The combination-type AFCI combines the protection of branch/feeder circuits with increased sensitivity as well as added protection for cord-and-plug-connected equipment. The proposal isn't the first mention of AFCIs in the Code; however, it is the most expansive and possibly the most controversial.

Like the impetus for all changes to the Code, the new requirement stems from proposals that were acted upon by Quincy, Mass.-based National Fire Protection Agency's (NFPA) committees of volunteer technical experts from the electrical community. “We support the consensus process,” says Mark Earley, assistant vice president and chief electrical engineer of NFPA. “What it is at this time is a proposal. There are a few more steps yet. The proposal that the committee has acted on expands the usage in residences, but we still have the public comment phase to get through. The committee may change its position based on the public feedback. It could change and be quite a bit different between now and then.”

Too much too late? The NEC first included the use of AFCI devices in its 1999 edition. Section 210.12(A) defines an AFCI as a device that provides protection from the effects of arcing by de-energizing the circuit when it detects an arc fault. Section 210.12 of the 1999 Code required that all branch circuits that supply 125V, single-phase, 15A and 20A receptacle outlets installed in dwelling unit bedrooms to be protected by an AFCI by Jan. 1, 2002. In the next Code cycle — the 2005 edition — combination-type AFCI protection was proposed for all 15A and 20A, single-phase 120V circuits in all dwelling units by Jan. 1, 2008. It is this issue that is currently under review.

Even though the requirements may change before they even go into effect, electrical industry professionals are already speculating as to the impact, if any, the requirements will have on public safety as well as the costs in both time and money for electrical designers, contractors, and inspectors.

In defense of the 1999 NEC AFCI requirements, which went into effect in 2002, the U.S. Consumer Product Safety Commission (CPSC), Bethesda, Md., cites that each year problems in home wiring, such as arcing and sparking, are associated with more than 40,000 home fires that are responsible for the deaths of more than 350 victims and 1,400 injuries. “The U.S. CPSC is an avid supporter of AFCIs and views the Code calling for AFCI installation in bedrooms to be a very positive life-saving standard,” says Scott Wolfson, deputy director, Office of Information and Public Affairs, CPSC. “Any work to expand the application of AFCIs throughout the home is supported by agency staff, and there is ongoing work to make AFCIs even more effective in terms of their sensitivity to electrical arcing and their ability to cut off what could be a life-threatening electrical fire.”

The NFPA narrowed the numbers down even further by blaming fixed wiring for 13,000 to 15,000 fires in U.S. homes, which cause more than 100 deaths and roughly 350 injuries per year. Both agencies claim that AFCIs provide protection against fires started by damaged wiring by shutting off the electrical circuit before the problem can become an ignition source. Others disagree.

“I was totally opposed to the 1999 Code change because I felt that something wasn't right about the technology,” says Mike Holt of Mike Holt Enterprises, Sunrise, Fla. “AFCIs are designed to protect the circuit conductor wiring. They're not designed to clear a fault in the event that something was plugged into a receptacle or a piece of equipment. It protects the wiring in the walls, and how many wires in the walls cause fires? More than likely, a fire would be caused by something plugged into a receptacle or a piece of equipment failing, and that failure doesn't have sufficient fault current to trip a regular breaker quick enough.”

Holt concedes that by including the combination-type AFCI in the wording of the Code, appliances and electronics plugged into a receptacle will now be protected from arcing or sparking. However, if the standard AFCIs did too little to protect, the combination-style AFCIs may do too much, rendering appliances unusable. “My concern is they've moved that threshold down from 75A to 5A,” Holt says. “Of course you want to protect people, but if the technology overshoots its goals and people can't run their vacuum cleaner or turn on the standard loads, it leaves the electrical industry in the middle.”

Holt proposes that the problem may lie with the appliances and electronics — not the AFCIs — but that's little consolation for the electrical industry, which may be held to the requirements in the near future. “Maybe the manufacturers of paddle fans and vacuum cleaners need to do a study and get with the manufacturers of the AFCI devices,” Holt says. “Do I think we're going to eventually work this all out? Sure. My understanding of the technology is that it will be better, but there are a lot of problems right now with the branch-circuit feeder AFCIs that haven't been resolved.”

Some industry insiders don't agree that appliances and electronics are incompatible with the combination-type AFCI devices. “I totally disagree with that,” says Keith Laughlin, former electrical inspector and current electrical industry educator in Richardson, Texas. “I've heard that in seminar settings but I have seen absolutely zero substantiated evidence that say that this appliance or that appliance is not compatible with an AFCI.”

Laughlin believes that not only are combination-type AFCIs compatible with appliances, but that they also will aid public safety by preventing house fires. “In 10 to 12 years from now, we'll look back and say, ‘Look at how the number of deaths in a dwelling due to fires has dropped. Now what caused that?’ I think you're going to have to look at the AFCI and say, ‘There's the reason for that drop in residential fires and deaths occurring from the same,’ so personally I'm a big proponent of AFCIs. As of right now, I don't think we have the evidence, but we'll see it in 10 years or so. I don't have to pay for them though.”

The bottom line The issue of who will pay for the extended use of AFCIs may be one of the deciding factors for the acceptance of proposal #2-142. Electrical designers, contractors, and inspectors may be the ones carrying the brunt of the increased costs, in both time and money. The difference in cost between a standard receptacle and one protected by an AFCI device could force contractors to face the choice between higher bids for their customers or lower margins for themselves. “It will be a dramatic change in cost,” Holt says.

In addition, Holt's argument extends to the burden the electrical and construction industry as a whole may carry with regard to the cost of installing AFCIs in every applicable outlet. An impromptu cost-benefit analysis certainly makes the technology seem cost-prohibitive. “Let's assume this technology saves 10 people a year, and let's say it costs $5 billion a year to do this, what does that come out to be? $500 million a person?” Holt asks. “If you put money somewhere else you may have a bigger return on your investment but is it cost-effective? Is it really practical?”

Some industry players are also concerned about the practicality of these devices and how they'll fit in with a homeowner's lifestyle. What happens if these devices prevent people from running their appliances? Will they hire someone to replace the outlets or change them out themselves? Some feel this problem will only worsen if the proposed plan to extend AFCIs throughout dwellings is approved.

Laughlin claims that residents tamper with with all technology put in dwellings but that fact shouldn't be the reason not to approve the new proposal. “I do see homeowner tampering,” Laughlin says. “You see that with anything. You can't limit that to just AFCIs.”

When the Code began requiring GFCIs some homeowners removed the devices, but the improved public safety numbers were still evident. “You can't protect someone from ignorance, from taking out an AFCI and replacing it with a normal receptacle because the regular receptacle doesn't cost as much as that AFCI when it goes to be replaced,” he says.

In Laughlin's experience, misinterpretation of the Code was the biggest problem in implementing the past changes with regard to AFCIs. “You got grumblings from an economic standpoint,” he says. “But most of it came from misinterpretation of the Code. A lot of contractors were saying, ‘Well, this is going to change the way that I've got to wire bedrooms. Now I've got to run an AFCI circuit in the bedroom, circle that bedroom, and dedicate that circuit.’ I don't know where they were getting that. Nothing said that the AFCI circuit had to be a dedicated circuit, so if you were running a circuit around the bedroom, and you had a receptacle in the same wall facing into the hallway or facing into the den, that receptacle's not required to be AFCI protected. It can be if you choose to put it on that circuit: Nothing said you couldn't do that. There were some grumblings, but it was from misinterpreting the Code.”

Inspect your gadget Ironically, the proposed AFCI requirements may make interpretation of the Code easier. According to Holt, inspection will only be a matter of looking for the breaker. “If there's a breaker on the panel, then you know it's not a problem,” he says. “If there's not a breaker on the panel, then there's a problem. The technology is very clear to identify.”

Concerns over time-consuming inspections could also be alleviated with the use of spot checking. “Inspectors are having to test AFCIs right now,” Laughlin says. “I suspect that even right now and in the future what you're going to get is spot checking. The inspector's not going to check every single circuit but would spot check one here and one there. I can't say that's how every inspector's going to do it, but that's what I suspect.”

Because the proposal would require AFCI protection on all 120V, 15A to 20A, single-phase outlets, confusion regarding what constitutes a bedroom outlet will no longer be a concern. “Inspectors were always having to answer questions, ‘What about the closet lights? Is that part of the bedroom? What about the smoke alarms?’” Laughlin asks. “Those were the kind of issues everyone was having to deal with. ‘I've got a switch in a bedroom that provides power to a floodlight outside. Does that require AFCI protection?’ Technically, that's not an outlet, but if you line up 10 inspectors, five of them would say ‘Yes, it is,’ and five of them would say, ‘No, it's not.’ With the new proposed changes all those questions would go away. If it's a 120V, 15A/20A outlet, and you're at a dwelling — if everything stays the way it's proposed, then it's got to be AFCI protected. The guesswork is gone. I don't think it's a problem: I think it's a solution.”

Currently, the public comments in support or opposition to proposal #2-142, submitted by the Oct. 20 deadline, are under review by CMP-2, which may accept, reject, or hold the comments that suggest changing or deleting this proposal. In late November, the panel will convene in Redondo Beach, Calif., where it will compile a report on the public feedback it has received on this issue, which will be published in the National Electrical Code Committee Report on Comments (ROC). Then, in February, the Technical Correlating Committee will consider the results of the CMP's work to correlate this and other related proposals. In June, at the NFPA's annual meeting, the NFPA membership will vote on the accepted proposals. Time will be allowed for challenges of the action to the NFPA Standards Council and appeal to the NFPA Board of Directors. The Standards Council then considers the entire record from initial proposal to last appeal and determines whether or not to release the new Code.

Editor's note: In writing this article, at least a dozen electrical contractors were contacted for comment — each one declining to weigh in on the matter. Therefore, we've presented two strong yet opposing views on the proposed NEC change in requirements for AFCIs. Although the time for public comment has passed, EC&M would still like to have your input regarding the proposed change. If you would like your opinion included in a possible future article on the installation of AFCIs, please e-mail Staff Writer Beck Ireland at [email protected]. Your comments may be published in a future print or online issue as we track the progress of this important issue.

Sidebar: Proposal #2-142

Recommendation: Revise 210. 12(B) as shown below:

(B) Dwelling Units. All 120V, single-phase, 15A and 20A branch circuits supplying outlets installed in dwelling units bedrooms shall be protected by a listed arc-fault circuit interrupter, combination type installed to provide protection of the branch circuit. Branch/feeder AFCIs shall be permitted to be used to meet the requirements of 210.12(B) until January 1, 2008.

Substantiation: For the past three NEC cycles, CMP 2 has reviewed extensive amounts of data and information pertaining to the benefits of AFCls for the protection of dwelling-unit branch circuits. After careful consideration, the panel decided to require AFCls on branch circuits that supplied bedrooms as a means to gain experience and to put the application in an easily defined area.

AFCIs have had an excellent track record in the field and their installation/use have found numerous wiring errors and in addition they have found wiring damage and equipment damage that could have been potential sources of fire. With the experience gained, it is an appropriate time to expand AFCls to all 15A and 20A branch circuits in the dwelling. There is no basis for limiting the protection to circuits that supply only bedrooms and the increased protection is needed for other circuits. This expansion will continue the effort to address fires of electrical origin in dwellings.

The text has been modified to apply to all 120V, 15A and 20A branch circuits that supply outlets in all locations. The second paragraph is proposed to be deleted since it is no longer applicable.

2-142 Log #3488 NEC-P02 Action: Accept

Number Eligible to Vote: 12

Ballot Results: Affirmative: 8 Negative: 4

Source: NFPA, Report on Proposals A2007

Sidebar: This Is a Test

According to Underwriters Laboratories, Northbrook, Ill., special equipment isn't necessary for testing of AFCIs. There isn't a reason for a test on circuits with AFCIs that wouldn't be conducted on standard circuits. If you choose to test the installation, it's possible to check it's properly functioning by pressing the test button after the device has been energized with 120V, as if in service. Pushing the test button, which imposes a simulated arcing condition on the circuit, should result in the device opening. If the device does not open, then the AFCI should be replaced. If the device opens and can be reset, then it is a properly functioning AFCI. The test button is the only recognized method for testing the proper operation of the AFCI.

You can also perform an insulation resistance test to verify that the wiring and connections are properly insulated. Disconnect all loads and verify that unconnected wire ends are insulated. To prevent AFCI and GFCI devices from being damaged by high voltage, disconnect the load wire to any device in the circuit. Use an insulation resistance tester that will apply a direct current voltage of at least 500V to the circuit you're testing. All resistance readings should be at least 1 megohm. The test should indicate that the insulation is intact and that an arc would not be likely to occur in the portion of the circuit tested.

Note: Neither of these tests identifies loose connections.

Sidebar: Arc Fault Versus Ground Fault Detection

There is a major difference between the functions of an AFCI as compared to a GFCI. An AFCI device protects against faults or damage to wiring and equipment that could initiate unwanted, fire-causing arcs, which can exceed 10,000°F, anywhere in the circuit. A GFCI device protects people who may come into contact with energized parts connected to receptacles.


  • Protects against fire hazards due to arcing conditions.
  • Currently required by the NEC on all circuits for bedrooms in dwellings.
  • Can be used in any 15A or 20A 120V circuit.
  • Includes overload and short-circuit protection.


  • Protects people from severe electrical shock.
  • Required by the NEC in bathrooms, kitchens, basements, garages, and outdoor receptacles.
  • Can also provide protection on pool pump, jacuzzi, hot tub, and wet bar.
  • Includes overload and short-circuit protection.

Sidebar: AFCI Categories

A branch/feeder device is installed at the origin of a branch circuit or feeder, such as at a panelboard. The device is designed to protect branch-circuit wiring and feeder wiring against the effects of arcing and also provides limited protection to branch circuit extension wiring. This device also provides limited protection to branch-circuit extension wiring (e.g. cord sets and power supply cords). It may be a circuit breaker-type device or a device in its own enclosure mounted at or near a panelboard. The category control number for branch/feeder AFCIs is AVZQ.

An outlet circuit AFCI should be installed at a branch-circuit outlet, such as an outlet box, to provide protection of cord sets and power-supply cords connected to it (when provided with receptacle outlets). It may provide feed-through protection of cord sets and power-supply cords connected to downstream receptacles. The category control number for outlet circuit AFCIs is AWCG.

The combination AFCI complies with the requirements for both branch/feeder and outlet circuit AFCIs. This device is intended to protect downstream branch-circuit wiring as well as cord sets and power-supply cords. The category control number for combination AFCIs is AWAH.

An outlet branch circuit AFCI should be installed as the first outlet in a branch circuit. It protects downstream branch-circuit wiring, cord sets, and power-supply cords. These devices also provide protection to upstream branch circuit wiring. The category control number for outlet branch AFCIs is AWBZ.

A portable-type AFCI is a plug-in device that connects to a receptacle outlet and features one or more outlets. It protects connected cord sets and power supply cords against the unwanted effects of arcing. The category control numbers for portable AFCIs is AWDO.

A cord AFCI is a plug-in device for connection to a receptacle outlet that protects the power-supply cord connected to it. The cord may be part of the device. The device has no additional outlets. The category control number for cord AFCIs is AWAY.

Power supply cords or cord sets are available with a leakage-current detection and interruption (LCDI) device, which is similar to an AFCI. When the LCDI senses leakage current flowing between or from the integral cord conductor, it interrupts the circuits at a predetermined level of leakage current. The category control number for leakage-current detection and interruption is ELGN.

Information for these categories can be found in UL's Online Certifications Directory at and on pages 5-6 of UL's “2005 General Information for Electrical Equipment Directory” (White Book).

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