Evaluation of indoor air quality of teaching buildings in colleges and universities in cold regions

In order to solve the problem of poor indoor air quality in teaching buildings of natural ventilation colleges and universities in cold areas, the temperature and humidity, CO2 concentration, wind speed and other parameters of 13 natural ventilation classrooms in a university in Xi’an were monitored. At the same time, 698 students′ subjective evaluation of indoor temperature, humidity and air quality were recorded. The results show that the average clothing thermal resistance in winter is 1.29 clo, and the indoor thermal neutral temperature is 20.7 ℃. Except for the humidity, the temperature and CO2 concentration in the tested classroom do not meet the requirements of national indoor air quality standards. Combined with the students′ evaluation of indoor air quality, it is concluded that the unreasonable use of doors and windows for ventilation has led to poor indoor air circulation, the overall environment comfort degree and satisfaction level the students percieved during class is low, such as by drowsiness, dry skin, decreased concentration, and emotional depression.