Have you ever wondered what an AFCI breaker is?  Perhaps a home inspector or electrician mentioned it, or perhaps you've read about it or saw it on the news, but chances are that you have never heard about this technology.  Simply stated, an Arc Fault Circuit Interrupter (AFCI) is a type of breaker that is designed to detect arc faults in your home's wiring and trips the breaker before those arc faults can cause a fire.  This is important because an average of 30,000 fires are caused each year in the U.S. by arc faults.

Do I have AFCI protection?

How can you tell if you have AFCI breakers in your house?  Well, check the electrical panels to see if any of the breakers have 'test' buttons and read the label carefully to see what type of breaker it is.  (GFCI breakers also have 'test' buttons)  The label will also tell you what type of AFCI you have.  Currently there are two types: Branch Feeder (abbreviated BRAF) and Combination type.  

Branch Feeder type AFCIs were the first generation and can dectect parallel (hot to neutral or ground) arcs.  The newer style Combination type can detect both parallel and series (like a loose wire connection) arcs.  The ability to dectect series arcs is important, because they are the more common style of arc.  If you have a panel with older BRAF type breakers, it would be prudent to replace them with the newer Combination type AFCI breakers.

What if I don't have AFCI protection?

AFCI technology first came onto the market in the mid-1990s and it is not possible to retrofit most older panels with newer AFCI breakers.  Also, there are currently no AFCI breakers that can work with a type of circuit called a multi-wire (shared neutral) circuit.  Most older homes, especially those that were built with knob and tube wiring utilized mulit-wire circuits.  This means if you wanted to install AFCI protection, you would have to rewire the circuits as well as installing new panels that could accept the newer AFCI breakers.

Whether the money spent upgrading the electrical system to install AFCI protection is 'worthwhile' will have to depend on the judgement of the home owner.  If it is as easy as swapping out breakers in a newer panel, it would seem to be a 'no-brainer'.  If a major electrical upgrade would be required, then the home owner would have to weigh the costs (money, inconvenience) versus the benefits (improved safety).  

Further Information

Still curious about AFCI protection?  Check out this video from the Electric Safety Foundation International, or this video for a more indepth explanation of the technology.

JMC Buildling Inspections has been doing building inspections for over 28 years