Optimized Ventilation Control for IAQ in Partial Renovation and Non-Renovated Commercial Buildings during the Summer Period in Chongqing, South West China

This paper reports on research to analyze the indoor air quality (IAQ) and the concentration and varying patterns of CO2, formaldehyde and TVOC in commercial buildings located in Chongqing, South-West China. Two buildings were monitored during the day over two weeks in the summer period. One was a completed building that had been fully operational for several years. This building is termed the ‘non-renovated’ building. The other was a commercial building of similar age that was currently undergoing renovation on one of the main retail floors. This building is termed the ‘partial renovation’ building. The results of the study show that indoor TVOC pollution is a prominent issue in commercial buildings with typical pollution rates exceeding recommended standard levels by 58.9% (partial renovation) and 19.6% (non-renovated), respectively. There were significant correlations between indoor environmental parameters, especially the three indoor air pollutants (p<0.05, Spearman). The three main factors influencing the concentration of the indoor air pollutants were: the time of the day; the floor layout; and the different retail functional areas in particular the supermarket, catering services, leather goods and cosmetics. The findings present proposals for optimized ventilation control strategies and contribute to the application of ventilation in similar commercial and business environments.