|
|
Comfort
There is no one temperature and humidity condition at which everyone is comfortable. People are comfortable at a range of temperatures and humidities. Research conducted over many years on large numbers of people by the American Society of Heating, Refrigeration, and Air Conditioning Engineers concluded there is a range of combined temperatures and humidities that provides comfort to most people. This chart shows indoor air temperature on the vertical axis, relative humidity on the horizontal axis, and a shaded area known as the "comfort zone." Notice that most people are comfortable at higher temperatures if there is a lower humidity. As the temperature drops, higher humidity levels are still within the comfort zone.
Until recently, it was general practice to design for 72° to 75°F and 35 to 40% relative humidity in winter, and 75° to 78°F and 50 to 55% relative humidity in summer. In the interest of energy conservation, in 1974 the federal government recommended lowering the winter temperature to 68°F and raising the summer temperature to 80°F for government buildings and encouraged private industry and homeowners to adopt similar practices.
