http://www.ul.com/regulators/afci/labdatav5n3.html http://www.ul.com/regulators/afci/Dini2.pdf
Why AFCI?
1) Suppose a lamp cord (as an example) has been pinched, so that part of the hot conductor is cut. It starts arcing between the strands upstream of the cut and the strands downstream of the cut. The current associated with the arcs flow along the wire, so the current on the hot wire always equals the current on the neutral. Therefore, a GFCI would not detect the event. The arcs are of high currents, but of low durations. Therefore, the branch circuit breaker would not detect the event. Continued arcing could lead to overheating, and to a fire. The AFCI device is designed to detect currents that display the signature of this type of arcing, and to trip before a fire could start.
(2) The code says to put AFCIs in bedrooms primarily because the industry would never accept an immediate change that required them everywhere. As a starting point, it was an easy enough sell. If time shows them to be effective, and if mass-production makes them cheap, you might see them as the one and only type of breaker in any new dwelling unit’s power panel
http://www.mikeholt.com/documents/ne...ment_page2.pdf
GFCI’s are required on all circuits with the potential of getting wet, I want to make this clear as NEC standards for the USA. You can use an AFCI on the branch breakers & install the GFCI outlets and this will work fine. I like Joe's set-up on a new installs but it does come with a nice price tag.