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)
“The human condition is such that pain and effort are not just symptoms which can be removed without changing life itself; they are the modes in which life itself, together with the necessity to which it is bound, makes itself felt. For mortals, the “easy life of the gods” would be a lifeless life.”
—Hannah Arendt (1906–1975)
“I don’t believe in villains or heroes, only in right or wrong ways that individuals are taken, not by choice, but by necessity or by certain still uncomprehended influences in themselves, their circumstances and their antecedents.”
—Tennessee Williams (1914–1983)