Attaching lights to the ceiling.

[ship]

I think it has more to do with protecting firefighters from accidentally cutting a live cable with an axe or something (although I would imagine that an axe would take out a conduit thats not EMT as well...) and getting zapped. That and the insulation would possibly melt... anyhow, these requirements get to be a pain when you have to have some sort of provision for video trucks to get signal from cameras all over the place in an arena to the truck outside. Running thru 500'+ of cable trays and short pipes thru walls is horrible, I can tell you.

Man... I'm way out of current code as I have seen all of this and done it over the years. But also I think that the above doesn't refer to DMX as temporary if of any help.