Abstract
INTRODUCTION: The use of respirators and masks has increased dramatically during outbreaks of respiratory infections, such as the COVID-19 pandemic. Both filtration efficiency and respirator fit testing influence the provision of effective respiratory protection to users. If healthcare workers (HCWs) do not have access to tight-fitting N95 filtering facepiece respirators (FFRs) or if fit testing procedures are not feasible, some cost‒benefit fit improvement strategies (FISs) could benefit HCW respiratory protection against respiratory infection pandemics. OBJECTIVE: The objective of this systematic review is to investigate the importance of fit testing and to identify the optimal factors influencing respirator or mask fit characteristics, particularly in emergency situations. METHODS: We searched four databases, including PubMed, Scopus, Web of Science, and Science Direct from February 5, 2020, to December 7, 2024, covering the COVID-19 pandemic period. Finally, a gray literature search was conducted to ensure that no further studies were missed. Additionally, quality assessment of the included studies was performed according to the Newcastle-Ottawa Scale. RESULTS: A total of 39 full texts were included in the systematic review. Seven categories of FISs included fitters or braces, double masking with cloth or medical masks over FFRs, ear loop knotting and tucking or using ear guards (hooks, clips), adhesive tape, skin protectants/dressings, wearing goggles over FFRs, and using cloths over facial hair to improve fit. Each FIS has its own advantages and disadvantages. Overall, there was an improvement in fitting after the application of the FISs. CONCLUSIONS: Among all, mask frame, ear loop strap modification, medical tape, thin dressings, double masking, and goggles donning modification are considered as pleasant FISs during performing the occupational activity. Among all, the mask frame and medical tape outperformed the other FISs. It is crucial that all respirators modified with FISs undergo standard fit testing procedures to avoid a false sense of security and prevent exposure to hazardous respiratory substances. Both safety and ergonomic factors are of great importance when applying each FIS.