"As the authors acknowledge, their study does NOT evaluate the ability of the
masks to shorten the trajectory of droplets emitted during coughing. The
function of the mask is to reduce how far aerosol droplets travel during
breathing, speaking, singing, sneezing, or coughing. This is the same reason one
should cover one’s mouth or nose with your forearm, inside of your elbow, or
tissue when sneezing. CDC guidelines advise the wearing of face coverings to
"slow the spread of the virus and help people who may have the virus and do not
know it from transmitting it to others.”
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