Humidity, which mainly means the amount of water vapor in the air, which is generally expressed in relative temperature RH. Humidity, temperature, air velocity and fresh air volume are the mainly influence factors for indoor air quality.

The environment temperature is higher in summer, and the higher air humidity will accumulate the heat of the air environment on the body surface, affecting the normal heat removal of the human body, making people feel damp and hot. The environment temperature is lower in winter, and the higher air humidity will accelerate the body surface. The loss of heat conduction affects the warmth of the human body, makes people feel wet and cold, and greatly reduces the somatosensory comfort.