The International Society for Respiratory Protection

pdf Vol. 37, No. 2, 2020 pp. 87 - 93 Grinshpun (Open Access)

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Novel Faceseal Technology Improves Outcomes of N95 Respirator Quantitative Fit Testing for Hard-to-Fit Individuals

Sergey A. Grinshpun, Richard H. Koehler, and Michael Yermakov

Background: The COVID-19 pandemic has highlighted the importance of respiratory protection for healthcare workers (HCWs) and patients alike. Presently, respiratory protective devices are worn in hospitals and healthcare settings globally. HCWs are generally required to wear N95 filtering facepieces respirators (FFRs) in high-risk settings and during certain high-risk procedures. According to OSHA, HCWs who are assigned NIOSH-approved N95 FFRs must be fit tested using either qualitative or quantitative testing protocols (QLFT and QNFT, respectively). However, HCWs often fail the initial fit test on the first N95 model chosen. A novel Faceseal technology was recently developed and successfully applied to commercial N95 FFRs. In this pilot study, we assessed how this technology affects the QNFT outcomes for subjects who had failed their initial N95 fit test.

Methods: Ten subjects who failed the QNFT with N95 FFRs on the first fitting were recruited to perform a QNFT study in which each subject was tested in triplicate on the same N95 model and with that same model modified with the novel Faceseal of a unique configuration, which is made of a thermoplastic copolymer, enhancing the respirator fit to the user’s face. The fit factors (FFs) and passing rates were determined, and the results were compared.

Results: The Faceseal technology increased the overall FF for the entire cohort from 59.8±18.3 to 163.2±27.3 (threshold=100) and the test passing rate from 10% to 90%. This improvement was achieved for the hard-to-fit subjects due to reduction of the faceseal leakage, as the filter and respirator body were left unchanged.

Conclusions: The novel Faceseal technology significantly improved the QNFT outcomes for individuals who had previously failed OSHA fit testing on the same N95 FFR.

Keywords: N95 filtering facepiece, faceseal, fit test