Fit Testing Disposable P2/N95 Respirators during COVID-19 in Victoria, Australia: Fit Check Evaluation, Failure Rates, and a Survey of Healthcare Workers

Abstract

Quantitative fit testing was utilised to evaluate the Department of Health and Human Services in Victoria (DHHS) recommended fit check and determine pass/fail rates for self-selected P2/N95 respirators. Survey experience and training related to P2/N95 respirators were also obtained. This was an observational study at a specialist tertiary referral centre, Melbourne, Australia, between 29 May 2020 and 5 June 2020. The primary outcome was quantitative fit test pass/fail results, with fit check reported against fit test as a 2 × 2 contingency table. The secondary outcomes were the number of adjustments needed to pass, as well as the pass rates for available sizes and types of self-selected respirators, survey data for attitudes, experience and training for P2/N95 respirators. The fit check predicts respirator seal poorly (PPV 34.1%, 95% CI 25.0–40.5). In total, 69% (40/58) of respirators failed quantitative fit testing after initial respirator application and is a clinically relevant finding (first-up failure rate for P2/N95 respirators). Only one person failed the fit test for all three respirator fit tests. There was significant variability between each of the seven types of self-selected P2/N95 respirators, although sample sizes were small. Few participants were trained in the use of P2/N95 respirators or the fit check prior to COVID-19, with a high number of participants confident in achieving a P2/95 respirator seal following a fit test. The fit check alone was not a validated method in confirming an adequate seal for P2/N95 respirators. Quantitative fit testing can facilitate education, improve the seal of P2/N95 respirators, and needs to be integrated into a comprehensive Respiratory Protection Program (RPP).