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:
“Then did they strive with emulation who should repeat most wise maxims importing the necessity of suspicion in the choice of our friends—such as “mistrust is the mother of security,” with many more to the same effect.... But notwithstanding the esteem which they professed for suspicion, yet did they think proper to veil it under the name of caution.”
—Sarah Fielding (1710–1768)
“Central heating, French rubber goods, and cookbooks are three amazing proofs of man’s ingenuity in transforming necessity into art, and of these, cookbooks are perhaps most lastingly delightful.”
—M.F.K. Fisher (b. 1908)
“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–?)