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Total outward leakage of face-worn products used by the general public for source control
Weihua Yang1, Warren Myers2, Mike Bergman3
1Department of Industrial and Management Systems Engineering, Statler College of Engineering and Mineral Resources, West Virginia University, Morgantown, WV; National Institute for Occupational Safety and Health, National Personal Protective Technology Laboratory, Pittsburgh, PA.
Background:
During Coronavirus disease 2019 pandemic, the general public used any face-worn products they could get to overcome the shortage of N95 respirators and surgical masks. These products, often not meeting any standards, raised concerns about their effectiveness in reducing the spread of respiratory viruses.
Methods:
This study quantified total outward leakage (TOL) of units from 9 face-worn product categories used by members of the general public. A benchtop system was devised to test 2 units from each category on 2 different-sized headforms with silicone elastomer skin. Each unit was donned 5 times per headform.
Results:
Both face-worn product category and headform size significantly affected TOL (P value < .05). The TOL of tested face-worn products varied from 10% to 58% depending on both model and headform size. Face-worn products donned on the medium headform had a higher mean TOL compared to those donned on the larger headform.
Conclusions:
Overall, single-layer cloth masks are the least effective measure for source control due to their highest TOL among the tested face-worn products. Three-layer disposable face masks may be a favorable option for source control among the public. A standard should be developed for face-worn product design and manufacturing to accommodate different facial sizes.
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