Variations in air quality before, during and after COVID-19 and impacts of air pollutants on contraction materials in Dhaka city

Abstract

We have done this study to determine the variations in air quality parameters before, during and after COVID -19 in Dhaka City. In recent years, Dhaka has been repeatedly reported as one of the most polluted cities in the world in terms of PM2.5 concentration and Air Quality Index (AQI). We also assessed the impacts of air pollutants on construction materials in Dhaka City. The degradation of many building materials is affected by climatic conditions and air pollution. Chemical environmental loads degrade not only metal components, but also other building materials. One of the research focuses is the construction of corrosion maps for substances, which will not only aid in material protection but may also serve in risk prediction during design, analysis, and maintenance. The purpose of this paper is to provide an overview of the changes in the occurrence of different Air Quality Index classes in Dhaka City during the lockdown period, as well as a comparison of PM2.5, NO2, SO2, and CO concentrations in Dhaka City air during the COVID-19-induced lockdown to the same period in previous years. This paper also includes attribution of missing data for AQI parameters from secondary data sources. Using a random forest algorithm to attribute missing data allows us to more efficiently analyze AQI data. Climate change and pollution play a role in the decomposition of a variety of building materials. Chemical environmental stressors degrade not just metal components but also other construction materials.