key: cord-0969080-n2n48kwe authors: Levine, Carly; Grady, Courtney; Block, Thomas; Hurley, Harry; Russo, Riccardo; Peixoto, Blas; Frees, Alexis; Ruiz, Alejandro; Alland, David title: Use, reuse or discard: quantitatively defined variance in the functional integrity of N95 respirators following vaporized hydrogen peroxide decontamination during the COVID-19 pandemic date: 2020-10-16 journal: J Hosp Infect DOI: 10.1016/j.jhin.2020.10.007 sha: 373ffa7c8e6da8c5ce18a1d11b037a59b03151b9 doc_id: 969080 cord_uid: n2n48kwe BACKGROUND: COVID-19 has stretched the ability of many institutions to supply needed personal protective equipment, especially N95 respirators. N95 decontamination and reuse programs provide one potential solution to this problem. Unfortunately, a comprehensive evaluation of the effects of decontamination on the fit of various N95 models using a quantitative fit test (QNFT) approach is lacking. AIMS: 1) To investigate the effects of up to eight rounds of vaporized hydrogen peroxide (VHP) decontamination on the fit of N95 respirators currently in use in a hospital setting. 2) To examine if N95 respirators worn by one user can adapt to the face shape of a second user with no compromise to fit following VHP decontamination. METHODS: The PortaCount Pro+ Respirator Fit Tester Model 8038 was used to quantitatively define functional integrity, measured by fit, of N95 respirators following decontamination with VHP. FINDINGS: There was an observable downward trend in the functional integrity of Halyard Fluidshield 46727 N95 respirators throughout eight cycles of decontamination with VHP. Functional integrity of 3M 1870 N95 respirators was significantly reduced after the respirator was worn, decontaminated with VHP, and then quantitatively fit tested on a second user. Furthermore, we uncovered inconsistencies between qualitative fit test and QNFT results that may have strong implications on the fit testing method used by institutions. CONCLUSIONS: Our data revealed variability in the functional integrity of different N95 models after VHP decontamination and exposed potential limitations of N95 decontamination and reuse programs. Functional integrity of 3M 1870 N95 respirators was significantly reduced after the respirator 40 was worn, decontaminated with VHP, and then quantitatively fit tested on a second user. Furthermore, we uncovered inconsistencies between qualitative fit test and QNFT results that As of October 2020, over 36.6 million people have been infected and 1 million have died 53 from COVID-19 worldwide [1] [15] for decontamination of N95 respirators. Both structural and functional returning the same model but from a different user post-decontamination. Yet, the integrity of 80 N95 respirators worn by multiple persons has not been investigated. Here, our first objective was to assess the number and type of N95 respirators 82 qualitatively fit tested and distributed by University Hospital (UH) in Newark, NJ before and 83 during the COVID-19 pandemic. Our goal was to provide a comprehensive evaluation of the 84 effects of VHP decontamination on the functional integrity of all currently used N95 respirators 85 using QNFTs. We then wanted to determine if N95 respirators could be returned to new users 86 following decontamination with no compromise to functional integrity. Finally, we evaluated the 87 reliability of qualitative fit testing on models that we found were hard to fit quantitatively by To define the scope of our targeted decontamination study, we examined N95 fit testing To analyze the effect of decontamination on N95 integrity we used a one tailed Kruskal- Wallis test. A one-tailed Mann-Whitney U test was used to assess the differences between N95 168 respirators worn by one user and N95 respirators worn by a second user following 169 decontamination. A p-value < 0.05 was considered significant. All statistical analysis was run 170 using Prism 8 software. We expanded our study to examine the possibility of inconsistencies between QLFT and QNFT results from hard-to-fit N95 models. Using both sweet and bitter QLFT measurements 220 followed by a QNFT, we determined that 5/6 participants who passed at least one qualitative fit 221 test were unable to pass quantitatively when testing the Gerson 1730 N95 respirator (Table I) . Unfortunately, we were unable to find enough participants able to qualitatively fit either Gerson 223 2130 or Cardinal Health N95 respirators and therefore they were not included in this study 224 (Table SI) . It is crucial that decontamination and reuse programs are able to rapidly turnaround 243 clean N95 respirators. One potential time saving approach is to return N95 respirators to new 244 users instead of having to sort and return respirators to their initial user. To assess the 245 adaptability of N95 respirators to a new face we quantitatively fit tested lightly worn respirators 246 on a second user following decontamination with VHP. Our results were limited to respirators 247 that were initially only worn for a QLFT and are thus not representative of the wear and tear 248 associated during an extended hospital shift. Despite these limitations, the QNFT values were 249 lower for 3M 1870 N95 respirators when they were lightly worn and fit tested by a second user 250 compared to the other respirator models tested. It is also possible that some respirators may be 251 less tolerant for reuse even by the same person, however we were unable to assess that in this 252 study. Although, others have found a significant association between number of shifts N95 253 respirators were worn by a single user and failed QLFTs [23] . These data bring to light a 254 significant obstacle for decontamination and reuse programs. existed between QNFT and QLFT results specifically on these hard-to-fit models. Of the ten 259 participants we recruited for QLFTs, six were able to pass at least one of the tasting challenges Together these observations suggest the administration of QNFTs may be warranted for fit 267 testing these hard-to-fit models and should be used to assess inconsistencies between QLFT 268 on other N95 models. We acknowledge that this study has several limitations. All fit testing methods can have An interactive web-based dashboard to track COVID-19 in real 301 time Transmission potential and severity of COVID-303 19 in South Korea. International journal of infectious diseases : IJID : official publication of the 304 International Society for A method to determine the available UV-C dose for the 338 decontamination of filtering facepiece respirators United States Department of Labor. Occupational Safety and Health Standards Personal 340 Protection Equipment: Respiratory Protection Comparison of 342 five methods for fit-testing N95 filtering-facepiece respirators Capability of respirator wearers to detect aerosolized qualitative fit 345 test agents (sweetener and Bitrex) with known fixed leaks Federal Drug Administration. Final Report for the Bioquell Hydrogen Peroxide Vapor (HPV) Decontamination for Reuse of N95 Respirators Fitting 363 characteristics of eighteen N95 filtering-facepiece respirators Smell and taste dysfunction in patients with COVID-19. The Lancet Infectious diseases 2020 Association of chemosensory 369 dysfunction and COVID-19 in patients presenting with influenza-like symptoms. International 370 forum of allergy & rhinology 2020 A New Symptom of COVID-19: Loss of Taste and Smell. Obesity 3M 1870 n = 4, 3M 9210 n = 4, Halyard Fluidshield 46727 n = 5, Cardinal Health n = 10