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This study conducted an experimental analysis of how indoor air quality (IAQ) is influenced by the outdoor air pollutants levels, infiltration rate, and occupants' behaviours. The impacts of these factors on IAQ were analyzed using on-site measurements and numerical simulations. The results contribute to a better understanding of how to control the Indoor Particulate Level (IPL) for the specific conditions of the studied building. Results showed that occupant behaviour was the primary factor in determining the IPL, significantly changing the number of outdoor particles introduced to the building. Moreover, it was found that the IPL was exponentially correlated to the Outdoor Particulate Level (OPL). Based on numerical simulations, this study concluded that smaller particles do not always have more chance than larger particles of accessing the indoor environment through the building envelope. Meanwhile, a steady-state indoor particle concentration numerical model was established and verified using the 4-fold cross-validation method. Finally, simulation results identified that the room infiltration rate had a positive linear impact on IAQ if the OPL was under 30 μg/m 3 . This is because the increased air exchange rate can help to dilute indoor air pollutants when the outdoor air is relatively clean., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Gestational exposure to ambient air pollution has been associated with Congenital Heart Diseases (CHDs). However, only a few studies, with inconsistent results, have investigated the effects of PM 2.5 exposure during early pregnancy. This study aims to evaluate the association between prenatal exposure to PM 2.5 and CHDs occurrence. We selected 782 births reported to have CHDs between 2007 and 2014 from the Taiwanese Birth Registry and randomly selected 4692 controls without any birth defects using a population-based case-control design. Data of exposure to ambient air pollutants, mainly PM 2.5 , PM 10 , CO, SO 2 , NO 2 , and O 3 during weeks 3-8 of pregnancy were retrieved from air quality monitoring stations and interpolated to every township using ordinary kriging. We applied unconditional logistic regression models adjusted for potential confounders to evaluate the associations. The results revealed a positive correlation between increased PM 2.5 exposure (adjusted odds ratio [aOR] = 1.21, 95% confidence interval [CI] = 1.03-1.42, per interquartile range change = 13.4 μg/m 3 ) during early pregnancy and overall CHDs occurrence. Furthermore, we found that atrial septal defect (aOR = 1.43, 95% CI = 1.01-2.02), endocardial cushion defect (aOR = 2.37, 95% CI = 1.01-5.58), and pulmonary artery and valve stenosis (aOR = 1.71, 95% CI = 1.06-2.78) were significantly associated with PM 2.5 exposures. No similar effects were observed for the other air pollutants. This study has demonstrated some positive associations between increased PM 2.5 exposure during the critical period of cardiac embryogenesis and certain CHDs occurrence., (Copyright © 2018. Published by Elsevier B.V.)