It is widely recognised that the COVID-19 virus (SARS-CoV-2) is primarily spread by aerosol transmission from infected persons (1). Good ventilation and air filtration can reduce the risk of transmission of this, and other viruses both within the workplace and other indoor venues.
Improving ventilation and air filtration are part of a multi-layered approach (the “Swiss Cheese Model”) recommended by epidemiologists and public health experts for risk mitigation. This is in part due to one of the characteristics of COVID-19 where “even people who are infected but do not have symptoms, or have not yet developed symptoms, can infect others” (2).
The WA State Government Department of Health has published a number of COVID-19 guidelines including a paper on COVID-19 Ventilation in Buildings (3) which includes “Employers have a duty under occupational health and safety laws to eliminate or minimise the risks of COVID-19 in the workplace, so far as is reasonably practicable.”
Methods and devices for Improving air quality to help minimise the risks of COVID-19 in the workplace may include:
- HEPA (high efficiency particulate air) filters;
- More effective heating, ventilation and air conditioning (HVAC) systems;
- Carbon dioxide monitors; and
- Ultraviolet light.
HEPA Filters. These filters remove 99.97% (H13 or H14) of aerosolized virus particles in the air (4). The filters can be either portable / standalone units, or integrated into the building’s HVAC system. As HEPA filters have a much finer mesh than standard HVAC filters, they require more power to filter the same amount of air in a given time.
Upgraded HVAC Systems. In addition to the use of the other items in this list, improving air quality via the HVAC system may include (5):
- Increase the introduction of outside air;
- Use of fans to increase the effectiveness of open windows;
- Adjusting HVAC systems to increase airflow to occupied spaces; and
- Running the HVAC system at maximum outside airflow for two hours before and at least one hour after the building is occupied.
Carbon Dioxide (CO2) Monitors. CO2 monitors provide an indicative risk of the possible spread of the COVID virus. High levels of CO2 indicate poor ventilation hence if the COVID-19 virus is present, it is more likely to be spread. A CO2 monitor showing levels greater than 800 ppm indicates the air indoors is not being refreshed fast enough with outside air (6).
Ultraviolet (UV) Light. UV light, specifically Far ultraviolet C (UVC) light, has been shown to effectively kill the COVID-19 virus (7). UVC has been widely used to kill pathogens in medical facilities, and is now becoming more common in non-medical facilities.
As highlighted in the TKO Fitouts’ article “Designing a Healthy Workspace”, a healthier worker is more likely to be a happy worker and a more productive worker.
References:1. https://www.thelancet.com/article/S0140-6736(21)00869-2/fulltext
2. https://www.health.harvard.edu/diseases-and-conditions/preventing-the-spread-of-the-coronavirus
4. https://sgeas.unimelb.edu.au/engage/guide-to-air-cleaner-purchasing
5. https://https://www.cdc.gov/coronavirus/2019-ncov/community/ventilation.html
7. https://www.sciencedaily.com/releases/2020/09/200917105345.htm