General ventilation refers to a ventilation system that encompasses an entire work space or area. General ventilation systems circulate fresh air through a work space through exterior air intakes. Air from outside the workplace is mixed with the indoor air. General ventilation of a workplace is only appropriate if the space does not generate high concentrations of fumes, dust, or other airborne contaminants. This is because a general ventilation system does not remove contaminants from the air, but merely dilutes them by mixing the work space's air with a fresh supply from outdoors.
A general ventilation system may also be used to control temperature and humidity within the workplace. General ventilation is sometimes called dilution ventilation or fresh air ventilation.