COVID and HVAC Filters

For Commercial and Industrial Systems

Twin City Filter Service is a premier supplier of high quality filters to the commercial and industrial HVAC filter community. We pride ourselves in the depth of our knowledge. And yes, the right filter, correctly maintained, can assist in the battle against COVID-19 in commercial and industrial buildings. To help our customers, friends and peers, we have gathered useful COVID filtration information as it pertains to the commercial and industrial HVAC filter community.

February 2022 Update. Resources: ASHREA, NAFA, REHVA, BOMA, IFMA, AFE, USGBC, International Filter News, The Wall Street Journal, Bloomberg.

Synopsis of facts most repeated in the literature:

Building air exchange rates should be no less than 3, with 3-6 preferred (a hospital rate is normally 12).
Medical buildings and most airplanes are designed for HEPA. Your building is likely not.
If your system is designed for it, use MERV 13 or higher.
If your system is not designed for MERV 13, use the highest MERV your HVAC system is designed for, and consider plans for building upgrades. Do not use filters with higher ratings than your HVAC system specs.

Read on and stay safe.

Why Air Filtration is so Important in the Fight Against Covid

This Bloomberg article points out how concerned we were about surfaces and how concerned we should be about aerosols and HVAC filtration.

University of Oregon Air Flow Animation

From the University of Oregon Institute for Health in Indoor Environments, an animation showing indoor aerosol fate and transport. The last simulation suggests greater air intake, perhaps via an Economizer.