2024 Yes CO2 concentration monitoring inside educational buildings as a strategic tool to reduce the risk of Sars-CoV-2 airborne transmission https://www.sciencedirect.com/science/article/pii/S0013935121008549?via%3Dihub Di Gilio, Alessia Europe Observational Epidemiological Modeling Teachers Elementary (K-5) Middle/Jr High (6-8) Carbon Dioxide (CO2) carbon dioxide (CO₂) COVID-19 SARS-COV-2 transmission risk mitigation Indoor ventilation conditions School re-opening NDIR sensor Real-time CO₂ monitoring was used in 11 Italian classrooms to assess and improve ventilation. Despite open windows, most rooms exceeded safe CO₂ levels. A tailored protocol with visible CO₂ data helped achieve better air exchange and reduce transmission risk. 2021