Abstract
Recirculating air purification technologies are employed as potential means of reducing exposure to aerosol particles and airborne viruses. Toward improved testing of recirculating air purification units, we developed and applied a medium-scale single-pass wind tunnel test to examine the size-dependent collection of particles and the collection and inactivation of viable bovine coronavirus (BCoV, a betacoronavirus), porcine respiratory coronavirus (PRCV, an alphacoronavirus), and influenza A virus (IAV), by a commercial air purification unit. The tested unit, the Molekule Air Mini, incorporates a MERV 16 filter as well as a photoelectrochemical oxidating layer. It was found to have a collection efficiency above 95.8% for all tested particle diameters and flow rates, with collection efficiencies above 99% for supermicrometer particles with the minimum collection efficiency for particles smaller than 100 nm. For all three tested viruses, the physical tracer-based log reduction was near 2.0 (99% removal). Conversely, the viable virus log reductions were found to be near 4.0 for IAV, 3.0 for BCoV, and 2.5 for PRCV, suggesting additional inactivation in a virus family- and genus-specific manner. In total, this work describes a suite of test methods which can be used to rigorously evaluate the efficacy of recirculating air purification technologies.
Original language | English (US) |
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Pages (from-to) | 2058-2069 |
Number of pages | 12 |
Journal | Indoor Air |
Volume | 31 |
Issue number | 6 |
Early online date | May 7 2021 |
DOIs | |
State | Published - Nov 2021 |
Bibliographical note
Funding Information:We thank the staff of the University of Minnesota Veterinary Isolation Facility for their support in ensuring proper experimental setup in this study. This work was supported by Molekule Inc.
Publisher Copyright:
© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Keywords
- air purifier
- coronavirus
- filtration
- influenza
- photoelectrochemical oxidation
- virus aerosols
- wind tunnel test