Ventilation Fan, 300 Cubic Feet per Minute - $35 (temecula)

Ventilation Fan, 300 Cubic Feet per Minute, includes rheostat to adjust speed of fan.
I installed this in the ceiling of a room in my former house which I used for smoking cigars and for having cigar parties with friends.
Even when six guys were smoking, the fan kept the air mostly free from smoke by drawing the air from the room into the attic, and there the smoke left the house in the attic eaves.
After all my friends left, I emptied the ashtrays and turned the rheostat (which I installed on the wall next to the light switch) down to "low.
" This kept the room in negative pressure so that NO SMOKE ever escaped into the rest of the house.