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ASSESSING THE EFFECT OF BEARD HAIR LENGTHS ON FACE MASKS USED AS PERSONAL PROTECTIVE EQUIPMENT DURING THE COVID-19 PANDEMIC
Citation:
Prince, S., H. Chen, H. Tong, J. Berntsen, S. Masood, K. Zeman, P. Clapp, W. Bennett, AND J. Samet. ASSESSING THE EFFECT OF BEARD HAIR LENGTHS ON FACE MASKS USED AS PERSONAL PROTECTIVE EQUIPMENT DURING THE COVID-19 PANDEMIC. Journal of Exposure Science and Environmental Epidemiology . Nature Publishing Group, London, Uk, 31(729788):953-960, (2021). https://doi.org/10.1038/s41370-021-00337-1
Impact/Purpose:
Over half of American men report keeping a beard at least occasionally. Except for N95 respirators, no guidance currently exists on the compatibility of facial hair with face coverings commonly used as personal protective equipment during the COVID-19 pandemic. These findings show that beard hair significantly impairs the performance of a variety of face coverings used as a primary preventive measure against infection with SARS-CoV-2. Also shown is a practical method to mitigate the loss of performance caused by beard hair.
Description:
Background: Globally, a large percentage of men keep a beard at least occasionally. Workplace regulations prohibit beards with N95 respirators, but there is little information on the effect of beards with face masks worn by the public for protection against SARS-CoV-2. Methods and findings: We examined the fitted filtration efficiency (FFE) of five commonly worn protective face masks as a function of beard length following the US Occupational Safety and Health Administration Quantitative Fit Test: N95 (respirator), KF94 and KN95, surgical/procedure, and cloth masks. A comparison using N95 respirators was carried out in shaven and bearded men. A detailed examination was conducted for beard lengths between 0 and 10 mm (0.5 mm increments). The effect of an exercise band covering the beard on FFE was also tested. Although N95 respirators showed considerable variability among bearded men, they had the highest FFE for beard lengths up to 10 mm. KF94 and KN95 masks lost up to 40% of their FFE. Procedure and cotton masks had poor performance even on bare skin (10-30% FFE) that did not change appreciably with beard length. Marked performance improvements were observed with an exercise band worn over the beard. Conclusions: Though variable, N95 respirators offer the best respiratory protection for bearded men. While KF94 and KN95 FFE is compromised considerably by increasing beard length, they proved better options than procedure and cotton face masks. A simple exercise band improves FFE for face masks commonly used by bearded men during the COVID-19 pandemic.
URLs/Downloads:
DOI: ASSESSING THE EFFECT OF BEARD HAIR LENGTHS ON FACE MASKS USED AS PERSONAL PROTECTIVE EQUIPMENT DURING THE COVID-19 PANDEMIC