How does the air's relative humidity impact comfort?

Relative humidity significantly impacts comfort primarily because it influences how quickly perspiration evaporates from the skin. When the relative humidity is high, the amount of moisture already present in the air inhibits the evaporation of sweat. Since sweating is the body's natural cooling mechanism, reduced evaporation leads to an increase in perceived temperature and discomfort. In lower humidity conditions, sweat can evaporate more quickly, enhancing the body's ability to cool down and improving overall comfort levels.

Understanding this relationship is essential for managing indoor air quality and temperature settings in HVAC systems, as it directly correlates with occupant comfort and satisfaction.