ECN Forum Forums Code Related Discussion NEC & other Code issues Removing 210.8 from 2005 NEC

My proposals for the 2005 code went into the mail this morning. One of the proposals calls for the deletion of 210.12 because AFCIs have no reasonable cost/benefit. Even if they were able to prevent 100% (which I'm sure everyone will agree is not possible) of the bedroom electrcial fires in newly constructed dwelling units, the cost per fire prevented after a ten years of compliance with the rule is over $665,000.00. Is this a reasonable cost/benefit? I don't think so.
Don

I am pretty much in agreement with Mike Holt's position that AFCI circuit breakers aren't capable of the functions and protection they are marketed under therefore creating a false sense of security and potentially creating a hazzard. There are too many ECs promoting their use in older homes wired without equipment grounds. They aren't listed for that application. What benefit are they in that application?
If AFCIs could really detect arcing faults-series and parrallel- as well as glowing loose connections I would be their biggest proponent.

I am not sure about removing 210.8. I saw a demo of the arc fault in action by Square D at the NECA trade show in Chicago. The technology does detect a bad arc from a "friendly" arc. It made a believer out of me. The rep said that they are not getting any complaints of nusiance trips. Some people were having trouble early on where the were using a shared nuetral (no more running a 3wire to pick up two bedrooms with a common nuetral).

I would like to see an exception that releives you from having to include 120 volt smoke detectors on a arc fault circuit if they are included in a bedroom. I am not sure if I have ever heard of a smoke detector arcing and actually starting a fire so why do they have to be included?

I applaud Mike H voicing the trades issue with AFCI's, 210.12 is full of holes....

The NEC has painted themselves in a corner, and they need to work it out to the satisfaction of the informed consumer, not lobbyist manufacture's.

This has moved me to my first ROP, which i'm sure will have plenty of company.

There is an alternative way of preventing fires, namely an over-all fire preventing GFI. (Sometimes used in Europe) The actual specification varies between countries, but the 300 mA time-delay type should be sufficient. There are two safety benefits to such a GFI:

1.) Reduced risk of fire in case of current to ground, when the fault path has too high resistance to trip the breaker. (Fault condition is not a "good" short or the ground conductor in poor condition, e.g. old corroded conduit.)

2.) Less risk of electric shock when a grounded object has become energized by a fault, but the current is too low to trip the breaker instantly. (In this case you can have 100 or so volts on the grounded object for several seconds.)

There is a major drawback to using a GFI in this way: In case of a real live-ground short both the breaker and the GFI will trip, leaving the house in darkness. Additionally, in this case the GFI was of no use.

In the case where the GFI trips, but the breaker does not, it may have saved someones life but the user will have to trip all the breakers before resetting the GFI, and then reset the breakers one by one to find the faulty circuit.

(I don't think nuisance trips is a problem with a 300 mA GFI. The time delay will also ensure that it won't trip if the fault occurs on a circuit protected by a "normal" GFCI, GFI-receptacle or AFCI.)

Just a thought.

Didn't we just have this big long discussion about the use of AFCI's? Whether they should be enforced in the NEC or not?