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Modeling the efficiency of UV at 254 nm for disinfecting the different layers within N95 respirators

Abdallatif Satti Abdalrhman, Chengjin Wang, Angelica Manalac, Madrigal Weersink, Abdul‐Amir Yassine, Vaughn Betz, Benoit Barbeau, Lothar Lilge and Ron Hofmann

Article (2021)

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The study presented a Monte Carlo simulation of light transport in eight commonly used filtered facepiece respirators (FFRs) to assess the efficacy of UV at 254 nm for the inactivation of SARS-CoV-2. The results showed different fluence rates across the thickness of the eight different FFRs, implying that some FFR models may be more treatable than others, with the following order being (from most to least treatable): models 1512, 9105s, 1805, 9210, 1870+, 8210, 8110s and 1860, for single side illumination. The model predictions did not coincide well with some previously reported experimental data on virus inactivation when applied to FFR surfaces. The simulations predicted that FFRs should experience higher log reductions (>>6-log) than those observed experimentally (often limited to ~5-log). Possible explanations are virus shielding by aggregation or soiling, and a lack of the Monte Carlo simulations considering near-field scattering effects that can create small, localized regions of low UV photon probability on the surface of the fiber material. If the latter is the main cause in limiting practical UV viral decontamination, improvement might be achieved by exposing the FFR to UV isotropically from all directions, such as by varying the UV source to the FFR surface angle during treatment.

Uncontrolled Keywords

decontamination, filtering facepiece respirators, Monte Carlo, N95 reuse, SARS-CoV-2, UV

Subjects: 1000 Civil engineering > 1000 Civil engineering
1000 Civil engineering > 1006 Hydrologic engineering
Department: Department of Civil, Geological and Mining Engineering
PolyPublie URL: https://publications.polymtl.ca/9249/
Journal Title: Journal of Biophotonics (vol. 14, no. 10)
Publisher: Wiley
DOI: 10.1002/jbio.202100135
Official URL: https://doi.org/10.1002/jbio.202100135
Date Deposited: 20 Jan 2022 16:20
Last Modified: 10 Apr 2024 00:19
Cite in APA 7: Abdalrhman, A. S., Wang, C., Manalac, A., Weersink, M., Yassine, A.‐A., Betz, V., Barbeau, B., Lilge, L., & Hofmann, R. (2021). Modeling the efficiency of UV at 254 nm for disinfecting the different layers within N95 respirators. Journal of Biophotonics, 14(10), 1-10. https://doi.org/10.1002/jbio.202100135


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