Assessment of the Total Inward Leakage Through Face Masks and Mask Sealers

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Visut Asanavijit
Panich Intra
Wisanapat Rattanachan


The objective of this work is to evaluate the total inward leakage through face masks and mask sealers. In this study, eight major categories of face masks including 1) surgical mask 2) two layer surgical masks 3) fabric mask 4) two-layer fabric masks 5) fabric mask over with surgical mask 6) N95 mask without valve 7) N95 mask with valve and 8) N95 mask with valve over with surgical mask, and two major categories of mask sealers including 1) seal frame on the outside of the surgical mask and 2) inner seal frame of the surgical mask. This work was carried out by the test method of the 29 CFR 1910.134, respiratory protection standard, OSHA for determining the total inward leakage through sample face masks and mask sealers for a target group of 5 peoples with different faces. It was found from the test results that the total inward leakage through surgical mask about 59.71%, two layer surgical masks about 31.76%, fabric mask about 62.80%, two-layer fabric masks about 53.60%, fabric mask over with surgical mask about 23.67%, N95 mask without valve about 0.91%, N95 mask with valve about 9.50% and N95 mask with valve over with surgical mask about 0.88%. For the mask sealers, it was found that the total inward leakage through the seal frame on the outside of the surgical mask about 7.54% and the inner seal frame of the surgical mask about 56.87%. The data from this test will be of great benefit to consumers and those interested in choosing each mask to suit their level of protection.


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Asanavijit, V., Intra, P., & Rattanachan, W. (2021). Assessment of the Total Inward Leakage Through Face Masks and Mask Sealers. Vajira Nursing Journal, 23(2), 1–13. Retrieved from
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