Subjective and objective sensory assessments of indoor air quality in college dormitories in Nanjing

Abstract

Indoor air quality (IAQ) is closely related to human health and work efficiency. The use of either subjective or objective assessments alone cannot adequately reflect IAQ and thus, is more reasonable to assess IAQ by combining them. In this study, the IAQ of 10 college dormitories was investigated using two subjective methods: field and laboratory sensory assessments, combined with objective measurements of CO2, formaldehyde, and total volatile organic compound (TVOC) concentrations. Two typical conditions, occupied and unoccupied, were studied. The results showed that 60% of dormitories under occupied conditions exhibited subjectively unacceptable odor. Further, 90% and 10% of dormitories failed to meet the objective assessments of CO2 and TVOC. Similarly, 80% of dormitories exhibited subjectively unacceptable odor under unoccupied conditions, whereas only 10% of dormitories failed to meet the objective assessment of TVOC concentration. Significant differences were observed between different IAQ assessment approaches, proving the necessity of combined objective and subjective methods. The difference between field and laboratory subjective odor assessments was significantly correlated with the field audiovisual environment dissatisfaction, indicating that differences in the audiovisual environment affected odor assessments. Furthermore, the adverse symptoms experienced by residents were correlated with the results of the laboratory odor assessments, indicating that odor may be an important indicator of the adverse effects of IAQ on human health.