As one of the leading authorities on HVAC, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has issued numerous recommendations to help businesses navigate the ongoing threat of airborne transmission of COVID-19 through their HVAC systems.
In their Position Document on Infectious Aerosols, ASHRAE reminds readers, "The risk of pathogen spread, and therefore the number of people exposed, can be affected both positively and negatively by the airflow patterns in a space and by heating, ventilating, and air-conditioning (HVAC)."
By following ASHRAE's recommendations, businesses can mitigate the risk of pathogen spread at their locations, helping to ensure the safety and comfort of their staff and customers.
Let's explore these recommendations to see how facility safety management has changed in light of COVID-19 — a critical step on the path to resuming "normal" operations.
To limit the risk of airborne exposure, ASHRAE recommends upgrading the minimum efficiency reporting value (MERV) of your HVAC filters to 13, or the highest level achievable for your system. While most residential and commercial HVAC systems currently use MERV 8 filters, a higher efficiency MERV can filter out even smaller particulate from the air.
According to one study from the American Society of Microbiology, "MERV 13 filters have the potential to remove microbes and other particles ranging from 0.3 to 10.0 µm [in size]." With respect to SARS-CoV-2 (the virus that causes COVID-19), the study explains, "SARS-CoV-2 has been observed in aerosolized particles in a spectrum of sizes, including 0.25 to 0.5 µm."
As you can see, MERV 13 filters can provide protection against most — but not all — instances of SARS-CoV-2 spreading via your HVAC system. Thus, making the switch to MERV 13 filters is a simple way for businesses to ensure their HVAC systems — and building occupants — are as protected as possible.
Furthermore, the study explains that air bypass (caused by gaps around the edges of HVAC box filters) in hospitals has previously contributed to the failure of HVAC systems to eliminate pathogens from shared air environments. With this in mind, it's critical that facilities choose a filter that can eliminate air bypass completely.
The PleatLink® filter system (available up to MERV 13) is a great opportunity for businesses to both boost their MERV value and eliminate air bypass in their HVAC systems. Custom engineered for your units, PleatLink® filters are a continuous media filter designed with an inch of overhang on all sides to create a gasket-like seal. When installed correctly, PleatLink® filters can completely eliminate air bypass in your units, ensuring contaminated air will not pass through unfiltered.
In addition to improving filtration, ASHRAE's Position Document on Infectious Aerosols recommends the following steps to increase both the volume and duration of airflow in your facility:
The goals of these efforts are to boost the overall volume of clean, uncirculated air in your space. While you might normally turn off your HVAC units outside of business hours or use recirculated air to increase energy efficiency, these procedures increase the risk of contaminated air lingering in your spaces.
It's important to use discretion with these recommendations; not every location will be able to use 100% outdoor air due to factors such as pollution or excessively hot, cold or humid weather. Use ASHRAE's recommendations as a guideline to help you tailor a plan that works best for your facility's safety management needs.
HVAC systems have long played a critical role in facility safety management, and that couldn't be more true with respect to COVID-19. As more and more businesses resume standard operations, facility managers should take a proactive approach to mitigating the spread of the virus using ASHRAE's recommendations.
If you'd like to learn more about how to incorporate these recommendations into your preventive maintenance routine, download BFC's new Infographic, 4 HVAC Safety Tips for Reopening Your Business During COVID-19!
About the Author
Rich Dorsey is the Director of Enterprise Solutions for BFC Solutions and has been with the company for 9 years. Outside of work, he enjoys spending time with his family, following SEC Football, and exploring the great outdoors. Contact Rich Dorsey at firstname.lastname@example.org