What about using compressed air to create a vacuum to pull air out of the cabinet. No mottor no sparks. Just locate the compressor out of the area and use a t to branch the air before the fitting for the airbrush. Use a watertrap on the air brush side, wouldnt need one on the evacuate side because no air is going into cabinet. Your most likely using a compressor for the airbrush anyway. Just a idea. The same principle is used in some bead blasting cabinets.