From the 03 IRC:
E3903.2 Luminaires near combustible material.
Luminaires shall be installed so that combustible material will not be subjected to temperatures in excess of 90°C (194°F).
I have seen in a hospital project where the mechanical guy was pizzed at the mechanical guy and vice versa. The mechanical guy came along and cut out the electrician's conduit and wires because it was in his way and ran his duct work there. The electrician came back and punched a hole in the duct work and ran his conduit through the duct. Silly but true.
