Retrofitting existing buildings to control indoor PM_2.5 concentration on smog days: Initial experience of residential buildings in China

Abstract

Severe smog days in many parts of developing countries, such as China and India, have drawn worldwide attention. This study aims at integrating various building retrofitting methods of existing buildings to control indoor particulate matter 2.5 concentrations. Methods are such as airtightness improvement, room pressure control, recycling air filtration and combinations of the above. The study verifies the effectiveness of each control method to reduce the indoor particulate matter 2.5 concentration below 25 mg/m 3 under certain outdoor conditions in building. Measurements and modelling are conducted for different outdoor particle concentration scenarios under different control strategies at an apartment in Shanghai, China. Overall, the retrofitting methods depend on outdoor smog circumstances and building structures. Therefore, it would be wise to choose appropriate control method depending on outdoor particulate matter 2.5 concentrations. This is the first time that various existing residential building retrofitting strategies are integrated jointly and the combination of different control methods are tested to ensure indoor air quality under different outdoor conditions. To validate the generality of these control strategies, a simulation model is developed and calibrated against experimental data under different scenarios. The variation of the indoor particulate matter 2.5 concentration in an extremely bad day is simulated and the influencing factors including infiltration air change rate, air volume and filter efficiency are all analyzed according to the model. The results and conclusions of this study can be used in many parts of the worlds, when building occupants have to choose proper equipment or retrofitting methods to control their indoor air quality. Practical application: The building retrofitting methods introduced in this article could be used in any residential building to control indoor particulate matter 2.5 concentrations continuously below 25 mg/m 3 under different outdoor conditions.

Identification of Factors Determining Household PM2.5 Variations at Regional Scale and Their Implications for Pollution Mitigation

“…Influencing factors can be studied using controlled experiments in selected settings or numerical models. − For example, a controlled experiment conducted in a domestic kitchen demonstrated significant impacts of cooking methods on indoor PM 2.5 concentrations, showing that deep frying results in an indoor PM 2.5 concentration more than 12 times higher than the background level, followed by pan frying, stir frying, boiling, and steaming . Shen et al developed a multivariate regression model to predict spatiotemporal variations and sources of indoor PM 2.5 based on simultaneous measurements in multiple indoor sites of a typical apartment .…”