Inclosing your paint to a smalller room , the fumes will be even more prodominate .
I have a mixing room next to my booth at work , and the door has to stay closed at all times , it has a fan that comes on when the lights are turned on , and it has a sprinkler system installed . All electric outlets need to be exlposion proof and OSHA approved ! A fire extinguisher on 2 walls .
You might take a read at this . May help shed some light .

http://www.epa.gov/dfe/pubs/auto/bp_mixing/

Spray