Used to be an exhaust fan.

Joy put a seat on the exhaust fan.

Joy put a seat on the exhaust fan.

Turn on the exhaust fan, will you, somebody?

He stopped by the exhaust fan and found cover

(f) Installation of smoke exhaust fans in mechanical equipment rooms to remove smoke more rapidly.

You gotta cut the power. That would shut down the exhaust fans.

There's an exhaust fan behind a four-foot grate in the west hallway. Use it.

That caused the furnace's exhaust fan to short out, and it disabled the alarm.

By making provision for exhausting smoke through building fans, the removal of smoke would be accelerated significantly;