Short answer NO 4 cu inches ( 65 cm cubed) allows for the end of a 14 / 2, no ground, nothing else. Fixture canopys add space but, unless they are marked with the Cu. In. they should not be counted. Almost anyplace that a pan box can be used an L shaped box, i.e. pan with a wiring compartment on one side, would do better. I once asked an engineer at Raco why they kept making the 3" pans and he said, Because inspectors kept allowing them to pass inspection. Alan--
410.10 Space for Conductors. Canopies and outlet boxes taken together shall provide adequate space so that luminaire (fixture) conductors and their connecting devices can be properly installed.
If the luminaire had a flat base that effectively stopped the box fill at the face of the box I could see the concern but if this is a bell canopy there should be plenty of room, even for two sets of #12s.
410.10 makes no mention of using the canopy of a fixture as space for branch circuit conductors, only the fixture conductors and their connecting devices. The branch circuit conductors are poperly housed in the box. If it were a 4" pan box it would properly house a single 14/2 WG NM cable and the fixture wires could be housed in the canopy. A 3" pan box is quite clearly not suitable for 14/2 WG NM cable but most of us, like Ryan would accept it.
[This message has been edited by George Little (edited 06-13-2006).]