2024 Yes Evaluation of Different Natural Ventilation Strategies by Monitoring the Indoor Air Quality Using CO2 Sensors https://www.mdpi.com/1660-4601/20/18/6757 Sánchez-Fernández, Ana Europe Observational Students Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Carbon Dioxide (CO2) Particulate Matter (PM) Temperature Humidity CO2 ventilation strategies monitoring Indoor air quality Pollution CO₂ monitoring in eight schools assessed how student presence, activity, ventilation, and break times affect IAQ. Results defined max occupancy and purge times by strategy. Surrounding pollution, noise, and building isolation also impacted IAQ. 2023