Bench testing of noninvasive ventilation masks with viral filters for the protection from inhalation of infectious respirable particles. Issue 3 (4th March 2021)

• Record Type: Journal Article
• Authors: Dellweg, Dominic; Haidl, Peter; Kerl, Jens; Maurer, Lukas; Köhler, Dieter
• Is Part Of: Journal of occupational and environmental hygiene. Volume 18:Issue 3(2021)
• Page Start: 118
• Page End: 127
• Publication Date: 2021-03-04
• Subjects: Infection -- pandemic -- respirator -- Sars-CoV-2 -- surgical mask -- virus; Industrial hygiene -- Periodicals; Environmental health -- Periodicals; Medicine, Industrial -- Periodicals; Occupational Health -- Periodicals; Environmental Exposure -- Periodicals; Environmental Health -- Periodicals; Occupational Exposure -- Periodicals; Hygiène industrielle -- Périodiques; Hygiène du milieu -- Périodiques; Médecine du travail -- Périodiques; 613.62
• DOI: 10.1080/15459624.2020.1862417
• Languages: English
• ISSNs: 1545-9624

Abstract

Abstract: During the beginning of the SARS-CoV-2 pandemic, there was a shortage of masks and respirators for the protection of health care professionals. Masks for noninvasive ventilation (NIV) in combination with viral-proof filters, worn by healthcare workers, could serve as an alternative protection measure. We determined the simulated protection factor (SPF) of such devices in comparison to conventional surgical masks, N95, and FFP3 respirators. Masks and respirators were mounted on a ventilated mannequin head in a test-chamber. Isotonic saline containing 150 MBq 99m TC-DTPA (99mTc-diethylenetriamine pentaacetate (DTPA) was nebulized inside the box. The aerosol had a mass median aerodynamic diameter of 0.6 ± 0.4 µm. SPFs were measured using radioactive DTPA particles in the mannequin test system by calculating the ratio of unfiltered particles (Pu ) and filtered particles (Pf ) for each tested device (SPF = Pu /Pf ). Simulated protection factors were 15.6 ± 3.6 for a ResMed AcuCare mask plus filter, 3.5 ± 0.2 for a ResMed Mirage Quattro FX mask plus filter, 9.5 ± 0.8 for a Loewenstein JOYCEclinc FF mask plus filter, 1.9 ± 0.2 for a surgical mask with a rubber band, 2.7 ± 0.7 for a surgical mask with ribbons, 2.3 ± 0.3 for an FFP3 respirator, and 3.6 ± 1.3 for an N95 respirator. The ResMed AcuCare and the Loewenstein JOYCEclinic FF mask were more effective than any other of the tested devices (p < 0.001). In conclusion, masks normally used for NIV with viral-proof filters can effectively filter respirable particles.