Vermont's chief inspector (thankfully retired) insisted the state's rules require afci's for service upgrades
this became impossible, due to multiwires
his response (and this was a good 10 years ago) was to go back and install them when they came to the market
his stance lost out to an nfpa ruling, i believe a Mr. Jeff Sargent may have been involved
that said i've sold a lot of afci's to residences with K&T, even sold an insurance company on it once
no, i don't tell them what the manufacturer claims (or in the case of UL1699, what they don't come clean on)
i just tell them it's enhanced protection
~S~
