Evaluation Of Indoor Air Quality In Commercial Buildings In Chongqing

With the great development of urbanization in China, the number of commercial buildings providing public services is increasing rapidly, which has become the primary unit of Chinese urbanization. The current researches of commercial buildings mainly focus on the energy consumption or thermal comfort, regardless of indoor air quality. Owing to numerous sources of indoor air pollution which has complicated varying patterns in commercial building, basing on the ‘key technologies of detection and operation and management of indoor air quality’, which is the sub-project of ‘the second five’ scientific and technological support projects, the researches of indoor air pollution by real-time monitoring and subjective questionnaire survey were conducted in Chongqing area. The purpose is to obtain the current situation of indoor air quality in commercial buildings in Chongqing and evaluate the indoor air quality of commercial buildings in Chongqing subjective with objective evaluation.The main works of this dissertation are shown as follows:(1) Two large commercial buildings in Chongqing urban area were selected for the research, real-time monitoring for a whole day of indoor environmental parameters, including temperature, relative humidity, wind speed, formaldehyde, carbon dioxide and TVOC every two months were conducted from 2013 December to 2015 February including winter, summer and transition season condition. Based on the testing results, current status of indoor air quality in commercial buildings in Chongqing can be obtained.The results show that the indoor air in Chongqing is polluted to a certain extent, and TVOC pollution is the most prominent pollution, formaldehyde and carbon dioxide followed. Overall it shows that the present indoor air quality of A which is located in core-commercial region is worse than that of B which is located in ordinary pedestrian street. The influencing factors of indoor air quality in commercial buildings include business hours, seasons and other time factors and architectural structure, sales area and other space factors.(2) The feeling toward indoor air quality of staff in commercial buildings and basic information of commercial buildings were obtained through subjective questionnaire survey. With combination of subjective results and testing results, the relation between indoor air quality satisfaction and concentrations of selected air pollutants was obtained. Furthermore, the limits for the concentration of TVOC, formaldehyde and carbon dioxide according with indoor air quality satisfaction are 0.677mg/m3, 0.105mg/m3 and 1113 ppm,respectively, and the proportion of impact of TVOC, formaldehyde and carbon dioxide toward indoor air quality satisfaction is 0.459, 0.519 and 0.453.(3) Based on the testing results and relevant documents, grey correlation analysis was selected as evaluation method from synthetical index method, fuzzy comprehensive evaluation, extension assessment approach, grey clustering analysis and grey correlation analysis, exceeding multiplicity method was selected as determining weight method from analytic hierarchy process, clustering weight method and exceeding multiplicity method. Then establish the evaluation system suitable for evaluation of indoor air quality in commercial buildings in Chongqing and conduct evaluation of indoor air quality of research objects.The evaluation results of indoor air quality according to the season, each sales area and each floor are in accordance with the analysis results of the present indoor air quality. Overall, the indoor air quality of B is better than that of A. The evaluation results of 28 testing points in the two commercial buildings show that the indoor air of-1-1,-1-2 in A and 1-5,3-3 in B and other testing point is need of urgent improvement.