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The science has demonstrated that risk reduction for COVID-19 transmission in classrooms specifically includes implementing masks, increased spacing, outdoor breaks, upgraded filtration, and improved ventilation. Increasing ventilation will reduce the buildup of virus containing particles in the classroom, thereby reducing the chance of long range transmission from occurring. Pre-pandemic, many classrooms did not meet standard ventilation guidelines, let alone recommended enhanced COVID-19 ventilation guidelines, due to energy concerns or malfunction equipment. People emit carbon dioxide (CO2) as we breathe, and CO2 concentrations build up in poorly ventilated spaces. During this talk, Dr. Dustin Poppendieck will discuss how CO2 concentrations can be used to quickly estimate ventilation effectiveness to find poorly ventilated classrooms and the challenges in assessing and interpreting CO2 readings from classrooms.
Poppendieck, D.
(2021),
Using CO2 as a Ventilation Clue, Collaborative on Health and Environment, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=933507, https://www.healthandenvironment.org/webinars/96581
(Accessed October 14, 2025)