Development of Hourly Indoor PM2.5 Concentration Prediction Model: The Role of Outdoor Air, Ventilation, Building Characteristic, and Human Activity

Abstract

Exposure to indoor particulate matter less than 2.5 µm in diameter (PM2.5) is a critical health risk factor. Therefore, measuring indoor PM2.5 concentrations is important for assessing their health risks and further investigating the sources and influential factors. However, installing monitoring instruments to collect indoor PM2.5 data is difficult and expensive. Therefore, several indoor PM2.5 concentration prediction models have been developed. However, these prediction models only assess the daily average PM2.5 concentrations in cold or temperate regions. The factors that influence PM2.5 concentration differ according to climatic conditions. In this study, we developed a prediction model for hourly indoor PM2.5 concentrations in Taiwan (tropical and subtropical region) by using a multiple linear regression model and investigated the impact factor. The sample comprised 93 study cases (1979 measurements) and 25 potential predictor variables. Cross-validation was performed to assess performance. The prediction model explained 74% of the variation, and outdoor PM2.5 concentrations, the difference between indoor and outdoor CO2 levels, building type, building floor level, bed sheet cleaning, bed sheet replacement, and mosquito coil burning were included in the prediction model. Cross-validation explained 75% of variation on average. The results also confirm that the prediction model can be used to estimate indoor PM2.5 concentrations across seasons and areas. In summary, we developed a prediction model of hourly indoor PM2.5 concentrations and suggested that outdoor PM2.5 concentrations, ventilation, building characteristics, and human activities should be considered. Moreover, it is important to consider outdoor air quality while occupants open or close windows or doors for regulating ventilation rate and human activities changing also can reduce indoor PM2.5 concentrations.

Long-Term Exposure to Fine Particulate Matter and the Deterioration of Estimated Glomerular Filtration Rate: A Cohort Study in Patients With Pre-End-Stage Renal Disease

“…In Taiwan, ambient air pollution has been a severe environmental problem and has attracted considerable attention from researchers and the general public (20,33,34). A widespread monitoring network was implemented beginning in 1998.…”

Personal PM2.5 Elemental Components, Decline of Lung Function, and the Role of DNA Methylation on Inflammation-Related Genes in Older Adults: Results and Implications of the BAPE Study

“…However, many studies have reported that exposure to PM 2.5 was not significantly or positively associated with the lung function in children and healthy adults. 22,25,52 Older adults spend most of their time indoors, 53 and many factors, such as outdoor-to-indoor permeability coefficient, 54 cooking, 55 and cleaning 56 have significant effects on indoor PM 2.5 exposure, which might cause misclassifications, especially when using ambient PM 2.5 concentrations to evaluate personal PM 2.5 exposure levels. Additionally, the response of the lung function to PM 2.5 varies with age, 57 smoking can increase the small airway resistance to environmental pollutants, 58 and individuals with acute or chronic diseases are more susceptible to air pollution, 59,60 which might partly explain the inconsistent results.…”

“…Previous studies have investigated the relationships between PM 2.5 exposure and lung function in children, healthy adults, and older adults and found that lung function decreased with increasing PM 2.5 concentration. − ,, Consistent with these studies, we found that personal PM 2.5 was significantly associated with the impairment of lung function in older adults. However, many studies have reported that exposure to PM 2.5 was not significantly or positively associated with the lung function in children and healthy adults. ,, Older adults spend most of their time indoors, and many factors, such as outdoor-to-indoor permeability coefficient, cooking, and cleaning have significant effects on indoor PM 2.5 exposure, which might cause misclassifications, especially when using ambient PM 2.5 concentrations to evaluate personal PM 2.5 exposure levels. Additionally, the response of the lung function to PM 2.5 varies with age, smoking can increase the small airway resistance to environmental pollutants, and individuals with acute or chronic diseases are more susceptible to air pollution, , which might partly explain the inconsistent results.…”

Comparison of Direct-reading and Gravimetric Methods of Particle Measurement in a Science Building, Silpakorn University

“…In this study, the TSI DustTrak monitor, utilizing a light scattering technique, was employed as the direct-reading instrument. It is one of the most popular direct-reading instruments and widely used for indoor air quality monitoring [7][8][9][10]. Its measurement range is from 0.001 to 400 mg m -3 for particle sizes between approximately 0.1 and 10 µm with a resolution of 0.001 mg m -3 or ± 0.1% of the reading, whichever is greater.…”