Necessity
When people or animals are present in buildings, ventilation air is necessary to dilute odors and limit the concentration of carbon dioxide and airborne pollutants such as dust, smoke and volatile organic compounds (VOCs). Ventilation air is often delivered to spaces by mechanical systems which may also heat, cool, humidify and dehumidify the space. Air movement into buildings can occur due to uncontrolled infiltration of outside air through the building fabric (see stack effect) or the use of deliberate natural ventilation strategies. Advanced air filtration and treatment processes such as scrubbing, can provide ventilation air by cleaning and recirculating a proportion of the air inside a building.
Read more about this topic: Ventilation (architecture)
Famous quotes containing the word necessity:
“Comes over one an absolute necessity to move. And what is more, to move in some particular direction. A double necessity then: to get on the move, and to know whither.”
—D.H. (David Herbert)
“I complacently accepted the social order in which I was brought up. I probably would have continued in my complacency if the happy necessity of self-support had not fallen to my lot; if self-support had not deepened and widened my contacts and my experience.”
—Mary Barnett Gilson (1877–?)
“No use saying necessity is making a mistake.”
—Mason Cooley (b. 1927)