Ventilation in university classrooms during the COVID-19 pandemic

The COVID-19 disease has caused a pandemic that forced schools and universities to stop in-person classes. To allow students back into a classroom environment, universities need to reduce the risk of COVID-19 through improved classroom ventilation Organizations have provided recommendations on reducing the risk of COVID-19, however there is a little information for institution who lack the resources need to evaluate and update their ventilation systems.

The aim of this study was to evaluate building design and ventilation expert knowledge to determine an “acceptable room ventilation”, based on the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the American Conference of Governmental Industrial Hygienists (ACGIH) recommendations. The end goal was to provide guidance for educational building mangers for assess classroom ventilation. The study assessed 12 lecture-based classrooms with a mix of thought to be adequate/inadequate ventilation qualities as well as mix of ventilation styles.

Half of the classrooms evaluated for ASHRAE 2004 design criteria passed the recommended and none passed ACGIH recommendations. Half of the classroom experts expected to pass, passed ASHRAE recommendations. Only three classrooms passed ACGIH recommendations with one of these classroom ventilation experts expected to fail. From these results, classroom design criteria and expert knowledge alone should not be used to assess building and classroom ventilation. A proper classroom ventilation assessment should include ventilation experts who are familiar with system and properly collect classroom ventilation data.