You might also think about a Positive Pressure booth. Instead of pulling fumes though a fan that would have to be Explosion proof, you could have a blowing or pushing fan pulling freash air though it and pushing it into the booth with an open vent at the opposet end to vent fumes outside. With that set up, a simple window box fan could do, or a DC that has a ducted outlet.
I used to work for this company over in Englewood CO. I'm not sure what they charge for their ventilators these days but I designed some of them and they're used mostly for ventilating manholes and other confined spaces, and they work really well:
http://pelsue.com/products/ventilation/centrifugal.html
They also have a line of axial ventilators, but they don't provide nearly as much static pressure as the centrifugal ones. They also have the 1590 which is a propane fired Axial Heater/Blower that I'd designed many moons ago, if you need to first warm the air.
http://pelsue.com/products/heating_ac/heating-1590.html
They also carry explosion proof ventilators if you are worried about the fumes getting up wind of the blower, or if you want the blower to pull the air instead of push it.
However, I still think you'd do better to push in fresh air instead of pulling out hazardous fumes.
_________________
Frank
WWACOAUX#1
"I love the smell of Sawdust in the morning, it smells like, victory."
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