When using a 1/2" deep pancake box, with a volume of 8", this volume is considered with a cover on the box, correct? If using one to install a ceiling fan, or any other fixture that does not have a plate that sits right on the fixture, is additional volume provided by the fixture?
I dont' think 370-16(a) applies because fixtures are not marked with volumes, but I'm also looking at 410-10.

Wow...

Yes, I was under the assumption that one could count the escutcheon (canopy) as part of the wire fill area, but 370-16(a) clearly states "...that are marked with their volume in cubic inches..." Could this mean that even if they marked the volume, but used the metric system (which the code uses at times and will next year) then it cannot be used?

Redsy,
good one. my code book is dogeared from Q's like this! Once again,years of assumption falls flat on it's face.... There must be some recourse for the lowly pancake box???

Virgil's found yet another hole in the wording of the Code! It's looking more and more like Swiss Cheese. Given 3 years to think & discuss, you'd think the CMP's would fill more of the gaps!

Just my opinion,

I think that you can't technically count the canopy space when figuring the box fill for your conductors. The canopy does however absorb the fixture wires (they're already there, right?) so that they do not have to be added into the box fill.
sound reasonable?

Bill