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:
“All real freedom springs from necessity, for it can be gained only through the exercise of the individual will, and that will can be roused to energetic action only by the force of necessity acting upon it from the outside to spur it to effort.”
—Anna C. Brackett (1836–1911)
“Nothing in the universe is contingent, but all things are conditioned to exist and operate in a particular manner by the necessity of the divine nature.”
—Baruch (Benedict)
“If necessity is the mother of invention, then resourcefulness is the father.”
—Beulah Louise Henry, U.S. inventor. As quoted in Feminine Ingenuity, ch. 13, by Anne L. MacDonald (1992)