Thanks for the vote of confidence, and in hindsight i see where you guys are coming from with people having less experience. All I can say to that is painting with urethanes (spelled it right ) is not soming to jump into.
One point I have to make though is how many people spray lacquers and urethanes in their garage? The answer is a LOT! And this is in the same room as furnaces, compressors, power tools etc etc etc. And again I ask how many explosions do you hear of? Very few!
A lot of the codes surrounding paint booths fall into the "protect me im stupid category". Think before you do and everything will be fine.
And your right about the spark, I've seen it myself. The proper procedure for "baking" a finsh would be to heat the room to approx 90 F. Remove the heaters and start painting. If the room is insulated enough it will keep the heat regardless of the air movement.
Electrics dont usally spark in the on or off position it's the tranzition between the two that does it. So turn the exaust fan on and leave it on, turn the heater on and then remove it after reaching temperature. Dont turn the lights on and off ....you see the drill.
I was thinking of making a video and I will post it when im done. To see actually how much atomized paint it would take to ignite. I'm curious now.