Advisory note on COVID-19 and HVAC

A.G. Coombs has published an advisory note that explores how COVID-19 may interact with HVAC systems and the steps that should be taken to reduce the spread of the virus.

Although the note confirms that – according to the most recent information – COVID-19 is mainly spread through respiratory droplets, it also indicates that there may be a small risk of airborne droplets entering HVAC systems.

“It is known that large droplets (>60 µm) normally are too large to remain suspended in the air and usually fall and land on surfaces. In some instances, some of the fluid can evaporate and the large droplets can transform into smaller particles called droplet nuclei and these can remain suspended in air. Droplet nuclei (2.5 to 10 µm) are believed to be able to remain suspended in air for hours and therefore be entrained into HVAC systems.”

With this in mind, the note details practical HVAC operational measures that can be considered along with possible design changes to reduce the likelihood of the virus spreading.

These include:

• Maintenance regimes and essential safety measures
• Cleaning and disinfection
• System commissioning and operation, and outside air rates
• Air filtration and cleaning options.

To read the advisory note, click here.