A coworkers daughter recently graduated with a degree in engineering. She recently began working for Siemens on some new AFCI products. She is looking for information. I have posted her question below and any assistance would be appreciated....

The history. Today, AFCI is only required on bedroom circuits. Beginning January 1, 2008 the National Electric Code (NEC) requires Combination AFCIs for entire branch circuit protection in residential construction. Combination AFCIs protect against series arcs as well as line-to-ground and line-to-neutral arcs.

The problem. The upcoming changes to the National Electric Code have warranted some debate from the homebuilders for 1 reason: there will be an increase in cost of building a home. Not only will a more expensive AFCI be required, but builders will have to buy more of them to cover each circuit. Their argument is they don't want to pay higher electrical costs when no proof exists that the installation of AFCI has reduced the number of electrical fires since the NEC implemented the mandate.

The solution. We need the statistics of electrical fires originating in bedroom circuits in houses less than x years old before AFCI requirements, where x is the number of years AFCI has been required in the particular area that controls the electrical codes. We then need to see the statistics of electrical fires originating in bedroom circuits in houses less than x years old after AFCI requirements were in place. The difference in these numbers is the important result. I realize these statistics would be very, very detailed. However, I cannot come up with other options that do not have flaws that could easily be pointed out.

The goal. We truly believe that combination type AFCIs provide more protection to homeowners, especially because fires caused by arc faults can strike at any time and burn undetected for a considerable amount of time before breaking into the open. It is important that we use irrefutable statistics as we battle organizations that want AFCI removed and will look for any flaw to discredit data.

Thanks for any information that can be provided.