Seven consumer-grade masks and five medical procedure mask modifications were fitted on an adult male volunteer, and FFE measurements were collected during a series of repeated movements of the torso, head, and facial muscles as outlined by the US Occupational Safety and Health Administration Quantitative Fit Testing Protocol.
Consumer-grade masks and medical procedure mask modifications were tested as personal protective equipment against a test aerosol of 0.05-μm NaCl particles. These analyses were designed to quantify the protection that masks offer to the wearer when exposed to others who may be infected.
The following consumer-grade masks were tested:
(1) A 2-layer woven nylon mask (54% recycled nylon, 43% nylon, 3% spandex) with ear loops tested with an optional aluminum nose bridge and non-woven-filter insert in place
(2) A cotton bandana folded diagonally once “bandit” style
(3) A multilayer rectangle according to the instructions presented
by the US Surgeon General
(4) A single-layer woven polyester/nylon mask (80% polyester, 17% nylon, 3% spandex) with ties
(4) A nonwoven polypropylene mask with fixed ear loops
(5) A single-layer woven gaiter/neck cover balaclava bandana (92% polyester and 8%spandex)
(6) A 3-layer woven cotton mask with ear loops
The baseline FFE of unmodified medical procedure masks with elastic ear loops was measured and compared with the FFE of the same type of mask with various modifications designed to enhance its function.
The following modifications were tested:
(1) enhancing the mask/face seal by tying the ear loops and tucking in the side pleats
(2) fastening ear loops behind the head with 3-dimensional–
printed ear guards
(3) fastening ear loops behind the head with a 23-mm claw-type hair clip
(4) enhancing the mask/face seal by placing a ring of three ganged rubber bands over the mask, with the center rubber band placed over the nose and chin of the participant and the left and right side bands looped over each ear
(5) enhancing the mask/face seal by sliding a 10-inch segment of nylon hosiery over the fitted mask
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