A systematic review of the challenge of quantitative fit coefficient of reprocessed filter respirators: The role of respirator models and disinfection methods

The aim of study was to review studies on the reusability of filter respirators and to evaluate their quantitative fit with respect to different respirator models and decontamination methods. We planned a search strategy according to the PICOT approach. We to find relevant publications, searched the electronic databases comprising Web of Science, Scopus and PubMed with appropriate keywords .After searching through 648 records in the databases, we found that 36 original studies met our eligibility criteria. Findings indicated that the UV, VHP , dry heat , and moist heat were the most investigated decontamination methods across included studies. The selected studies assessed 60 different respirator models. Results suggest some decontamination methods may work better on a certain model of respirator. However, we found that respirators decontaminated with VHP (also AHP and IHP, but based on limited studies), moist heat, and EtO or PAF (also based on limited studies) were the best performance in the fit factor. Furthermore, we observed some variation in fit factor between respirators and/or within individuals using dry heat, microwave, UV, ethanol immersion, MBL, and CIO2 methods. On the other hand, upon decontaminating the respirator models using autoclave, HPGP, VHP + O3, and LTSF methods, we found the fit performance unacceptable. Based on the change in fit performance, this study suggests that VHP and moist heat are the most promising ways to clean respirators for reuse. However, to account for individual differences, more research is necessary, particularly in clinical field studies with a larger number of participants.