Fans are often used to ventilate agricultural buildings. Adjoining rooms with connecting air paths through open doors or manure channels can operate as a single room with a common negative pressure.

Mixed-flow impeller systems exhaust laboratory workstation fume hoods, prevent reentrainment into the facility and adjacent facilities, and help companies comply with appropriate pollution-control ...

In most fan systems a single fan is selected for the required system design rating. Various methods of control are employed such as dampers, variable inlet vanes, variable pitch blades, or variable ...