Open Windows to Prevent the Spread of COVID-19

Air conditioning units may spread contaminated air

April 20, 2020

Facility managers preparing their buildings for the end of shelter at home orders may want to clean their air conditioning units and filters as well as consider opening up the windows. A new study published in the journal mSystems found facilities with air delivery systems should avoid recirculating indoor air as it could potentially increase the spread of the SARS-CoV-2 virus, which causes COVID-19, Newsweek reports.

The most direct way to avoid recirculating air is to simply open windows. However, as weather may prevent this action and not all commercial buildings have windows that can be opened, the next best option is to keep HVAC systems cleaned and maintained as well as air filters properly installed. HVAC systems with higher rates of air exchange may help dilute indoor contaminants, including viral particles. Separate air filtration systems may not be effective as the majority of viruses, including coronaviruses, are too small to be captured in the filter system.

The humidity of a building also may affect the spread of infections such as COVID-19. Limited data available on the novel coronavirus indicates it is active 15.9 hours on plastic surfaces at a relative humidity of 40%, compared to 2.74 hours at a relative humidity of 65%. Targeted in-room humidification could help prevent the spread of COVID-19. However, facility managers must be careful to keep humidity below 80% as that could create other problems, such as mold.

Experts in the built environment and microbiology at the University of Oregon in Eugene, Oregon and the University of California, Davis, made the recommendations after reviewing existing studies on various germs including SARS-CoV-2, SARS, and MERS. They are hopeful their findings will help those tasked with deciding when and how to ease social distancing measures.

Learn more about how your building’s HVAC system and vents may be spreading airborne contaminants.

 

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