Student learning performance and indoor environmental quality (IEQ) in air-conditioned university teaching rooms

This study investigates the relationship between Indoor Environmental Quality (IEQ) and learning performance in air-conditioned university teaching rooms via subjective assessment and objective measurement. Together with the data of air temperature, relative humidity, air speed, mean radiant temperature, CO₂ concentration, equivalent sound pressure level, horizontal illumination level, occupant activity and clothing insulation level measured in four classrooms and four large lecture halls, self-reported learning performance (in calculating, reading, understanding and typing) and perceived IEQ are evaluated. The results show strong associations of the overall IEQ votes with the environmental parameters. While thermal comfort, indoor air quality and visual environment are of comparable importance, aural environment is the major determining factor. The study also reveals that all IEQ complaints have similar impact on learning performance and there is a good correlation between learning performance and the number of complaints. To aid design needs, empirical expressions that approximate the impact of unsatisfactory IEQ on learning performance loss are proposed.