2022 Yes https://www.sciencedirect.com/science/article/pii/S0360132322009477 Rodríguez, Diana Europe Exposure Study Modeling Middle/Jr High (6-8) High School (9-12) Carbon Dioxide (CO2) Particulate Matter (PM) Ozone (O3) Nitrogen Dioxide (NO2) Classrooms Ventilation Indoor air quality Hygrothermal comfort Airborne transmission COVID-19 infection risk University classrooms, particularly the mechanically ventilated one, presented better ventilation conditions than the secondary school classrooms, as well as better thermal comfort conditions. The estimated Hr for COVID-19 ranged from intermediate (with surgical masks) to high (no masks, teacher infected). IAQ was generally good in all classrooms, particularly at the university ones, with I/O below unity, implying an outdoor origin of gaseous pollutants, while the source of PM was heterogeneous.