You can always use a belt driven fan and put the motor in another room or enclosure so only the fan is in the fume path, I myself have painted complete cars with a non enclosed fan, yes I know the risks. I also sprayed lacquer for a living daily at a cabinet shop with a similar fan, it actually took a build up of lacquer and not the fumes to eventually catch fire and it was like 7 years after the fan was installed and we sprayed pretty much 5 days of the week, make sure and keep them blown out as like I mentioned the build up was actually what caught fire and not the fumes!