As COVID-19 cases surge across the U.S. and Canada, this study is a reminder of the connection between ACH (Air changes per hour) and COVID-19 outbreaks.

Buildings have been associated with spread of infectious diseases, such as outbreaks of measles, influenza, and Legionella. With SARS-CoV-2, the majority of outbreaks involving 3 or more people have been linked with time spent indoors, and evidence confirms that far-field airborne transmission (defined as within-room but beyond 6 feet) of SARS-CoV-2 is occurring.

Conclusion

“Increasing air changes per hour and air filtration is a simplified but important concept that could be deployed to help reduce risk from within-room, far-field airborne transmission of SARS-CoV-2 and other respiratory infectious diseases. Healthy building controls like higher ventilation and enhanced filtration are a fundamental, but often overlooked, part of risk reduction strategies that could have benefit beyond the current pandemic.”