2024 No Quantifying indoor air quality determinants in urban and rural nursery and primary schools https://www.sciencedirect.com/science/article/abs/pii/S0013935119303317 Branco, M.C.M. Europe Review Elementary (K-5) Temperature Humidity Carbon Dioxide (CO2) Carbon Monoxide (CO) Particulate Matter (PM) Volatile Organic Compounds (VOCs) Ozone (O3) Nitrogen Dioxide (NO2) children Nursery and Primary schools Exposure Indoor air quality Monitoring in 101 rooms across 25 schools found high PM2.5 and CO₂ levels, especially in urban areas. Key predictors included background pollution, flooring, humidity, and heating. Results support ventilation, cleaning, and design improvements. 2019