On Sunday, March 26, 2017 at 11:03:02 AM UTC-4, wrote:
On Sun, 26 Mar 2017 07:40:48 -0700 (PDT), trader_4
wrote:

Please cite for us the code section that requires AFCI to be on an AFCI.

I assume you mean "that requires smoke detectors to be on an AFCI"

210.12 Arc-Fault Circuit-Interrupter Protection. Arc fault
circuit-interrupter protection shall be provided as required
in 210.12(A) (B), and (e). The arc-fault circuit interrupter
shall be installed in a readily accessible location.
(A) Dwelling Units. All 120-volt, single-phase, 15- and
20-ampere branch circuits supplying outlets or devices installed
in dwelling unit kitchens, family rooms, dining
rooms, living rooms, parlors, libraries, dens, bedrooms,
sunrooms, recreation rooms, closets, hallways, laundry areas,
or similar rooms or areas shall be protected by any of
the means described in 21 0.I2(A)(l) through (6)...

... and goes on to list all of the acceptable types of AFCI
That is pretty unambiguous.
Bear in mind an "outlet" is "A point on the wiring system at which
current is taken to supply utilization equipment" (Article 100)

Which again is exactly what I said. That the code doesn't
specifically say that smoke detectors must be on an AFCI,
only that the outlets in certain locations must be and
that it's when a smoke detector is in one of those areas
that it becomes covered, just like a receptacle would.
What you cite is current code, which again, I said results
in smoke detectors being on AFCI by virtue of where they
are located because now bedrooms and hallways are required
to have AFCI.

BUT, the poster's home was built in 2005. And I believe
back then, AFCI was not required in hallways, only in
bedrooms. So, I believe his home could have smoke
detectors in hallways outside a bedroom on a non-AFCI
circuit and it could have been code compliant then and
it's still grandfathered today.