Updated public health document includes extensive HVAC & COVID resources

Public Health Ontario has released new research on the role of HVAC systems in stopping the spread of COVID-19 indoors. The updated document is the result of a far reaching search of current research, and includes a long list of live-linked resources and studies from around the world.

The document, Focus on Heating, Ventilation and Air Conditioning (HVAC) Systems in Buildings and COVID-19, replaces the previously released Frequently Asked Questions (FAQ) on COVID-19: Heating, Ventilation and Air Conditioning (HVAC) Systems in Buildings. It includes additional evidence on the role of HVAC systems, humidity, air flow and CO2 on COVID-19 transmission.

Current research shows that improving indoor air quality (IAQ) through ventilation and filtration can stop the spread of COVID-19 by removing and diluting virus-laden particles from indoor air. However, ventilation and filtration alone are not enough to control the risk of transmission, especially when people are in close contact.

The document notes that air flow from fans can also impact transmission. Avoiding direct air flow at head levels can reduce respiratory droplets being transmitted from person to person, and fans should be directed so that air is drawn upwards or out of an open window while other windows draw fresh air in.

Other topics include recirculation of indoor air; HVAC measures to minimize the risk from infectious aerosols; air change rates required; and indoor carbon dioxide (CO2) measurement as an indicator of ventilation.

To download the document visit Public Health Ontario