Humidity Control
The Key To The Perfect & Fabled “Room Temperature”
HUMIDITY BY DEFINITION
The relative humidity (RH or ϕ) measures the amount of water vapor in the air compared to the maximum amount it can hold at a certain temperature.
Relative humidity is normally expressed as a percentage; a higher percentage means that the air–water mixture is more humid.
Humans are particularly susceptible to the effects of high humidity, as our bodies depend on evaporative cooling to expel excess heat. When the air is humid, perspiration evaporates at a slower pace, making it more difficult for the body to cool itself. As a result, the body perceives a higher air temperature, leading to increased discomfort in high humidity compared to lower levels, even when the actual air temperature remains constant. For example, at an air temperature of 75°F, 100% relative humidity can make it feel like 80°F, while 0% relative humidity would make it feel like 69°F.
This clearly illustrates the significant impact of high humidity on the body's ability to regulate its temperature. Heat index and humidex are indices that reflect the combined effect of temperature and humidity on the body's cooling mechanism.