I would like someone to tell me if an AFCI breaker is supposed to trip when an electric blanket that is plugged into an AFCI protected circuit developes an arcing fault. Or a portable space heater. Or an extension cord ran under a throw rug. Or any other cord connected equipment that developes a break in a conductor that begins arcing. I have set these situations up in my shop and have not had an AFCI breaker trip under any of these conditions. It is my opinion that these types of arcing are what cause the majority of home fires that are caused by arcing. Most fires(again in my opinion)that start in bedrooms of homes are not electrical at all. They are smoking related.
I just haven't had anyone who's been willing to tell me that an AFCI will see and interrupt an arcing fault in an electric blanket before a non-AFCI breaker would.(parrallel fault).
