Impact of individual IEQ factors on passengers' overall satisfaction in Chinese airport terminals

In this paper, objective environmental measurements and subjective questionnaire surveys are conducted in 8 major Chinese airport terminals to investigate Indoor environment quality (IEQ) and explore the relationship between individual IEQ factors and overall satisfaction. The objective measurements show that the qualification rate of indoor thermal environment is above 70%, according to Chinese thermal standard; the average CO2 concentration is controlled between 350 PPM and 700 PPM; the average value of natural light illuminance ranges from 300 lx to 500 lx; and the noise intensity stays at a high level, whose average value is between 55 dB(A) and 70 dB(A). The analysis of subjective surveys finds the majority of passengers are just satisfied with IEQ in the airport terminals. It is also found that the subjective satisfactory level is highly correlated with the objective environmental measurement. Based on Kano's model, the impacts of individual IEQ factors on overall satisfaction are analyzed. The results indicate 'Thermal Comfort' and 'Space Layout' are Basic Factors, which have prominently negative influences on passengers' overall satisfaction when they are underperformed. Conversely, 'Service Facility' is Bonus Factor, which means a greater positive effect on overall satisfaction if it performs well. In addition, 'Acoustic Quality', 'Air Quality' and 'Lighting' are Proportional Factors, whose impact on overall satisfaction is in linear proportion to its performance.