All I know is I built a spray booth from 2 long moving boxes. I cut a square hole near one end to fit a standard air conditioning filter, which I tape onto the outside of the box. I squeeze a standard 30" box fan against the filter with an bungee cord, so it sucks air through from the inside of the box.
Don't know if it's a brushless motor, it's just a standard 110 VAC (US) fan. I get so little paint coming through the filter that none, not even red, can be seen on the fan blades. And none on the wall right where the fan blows. So I figure any paint fumes are below any explosive limit, and go about my painting. Of course I open the shop to the outdoors when painting.
I would have attached pictures but the file sizes are 640K, WAY too big for MBM.