The world is still looking for all sorts of measures to be dealing with the COVID-19 pandemic. The SARS-CoV-2 virus is far from being ‘just a flu’ as some people want us to believe, and the enormous evidence prove it. Over 860,000 people died worldwide, and more than 26 million got infected.
Even since the start of the pandemic, wearing a facemask is one of the most widespread measures for slowing down the spread of the COVID-19 disease. But as usual, people tried all sorts of alternatives for what the doctors recommend, and thus the face shields alone and face masks with exhalation valves were taken more seriously. But is it really a good idea?
An authorized facemask is much more reliable
Thanks to researchers from Florida Atlantic University’s College of Engineering and Computer Science, we have a better idea of how face shields and masks with valves perform for impeding the spread of aerosol-sized droplets. The researchers used qualitative visualizations for that matter.
More precisely, the researchers employed flow visualization in a laboratory setting by using a laser light sheet and distilled water and glycerin to generate the material that made up the content of a cough-jet. They observed droplets expelled from a mannequin’s mouth while coughing and sneezing. Due to a plastic face shield and a facemask equipped with a valve, the researchers were able to map out the paths of droplets. Although face shields managed to block the forward motion of the jet, the expelled droplets were able to move around the visor with relative ease.
Manhar Dhanak, co-author of the paper and Ph.D., department chair, professor, and director of SeaTech, declared:
“From this latest study, we were able to observe that face shields are able to block the initial forward motion of the exhaled jet, however, aerosolized droplets expelled with the jet are able to move around the visor with relative ease,”
He further added:
“Over time, these droplets can disperse over a wide area in both lateral and longitudinal directions, albeit with decreasing droplet concentration.”
There you have it, the good old classical surgical facemask is much more effective against COVID-19. May the Natural Selection be on our side!
The new study was published in the journal Physics of Fluids.