Masks that are not enough to stop COVID-19 from moving away

WASHINGTON, December 22, 2020 – Just wearing a mask may not be enough to stop the spread of COVID-19 without going social distance.

In Physics of wetness, by AIP Publishing, researchers tested how five different types of mask products affected the spread of coronavirus-carrying droplets when we cough or sneeze.

All of the materials tested significantly reduced the number of droplets released. But at distances of less than 6 feet, enough drops that could cause illness were still being made through several of the products.

“A mask will definitely help, but if the people are very close, there is still a chance to spread or contract the virus,” said Krishna Kota, an associate professor at New Mexico State University and one of the authors in the article. “It’s not just masks that help. It’s both the masks and the speed.”

At university, researchers built a device that uses an air generator to simulate human coughs and sneezes. The generator was used to blow tiny particles, such as the air droplets by coughing and coughing, through laser beams into a tight square tube with a camera.

They blocked the flow of the droplets in the tube with five different types of mask materials – regular cloth mask, double-layer cloth mask, wet double-fold cloth mask, surgical mask, and N-level medical mask. 95 masks.

Each of the masks captured most of the drops, from the regular cloth mask, which allowed about 3.6% of the drops to pass through, to the N-95 mask, which statistically stopped 100% of the drops . But at distances of less than 6 feet, even those small percentages of drops can be enough for someone to get sick, especially if a person with COVID-19 sneezes or coughs multiple times.

One cyan can carry up to 200 million tiny virus products, depending on how sick the carrier is. Even if a mask blocks a large percentage of these grains, it could be enough to escape to get someone sick if that person is close to the vehicle.

“Without a face mask, it’s almost certain that a lot of foreign germs will move to the affected person,” Kota said. “Wearing a mask provides great protection, but it is not complete, for a person who tends to reduce the amount of foreign air snow and cough drops that would enter the person without the mask. . Consideration must be given to minimizing or avoiding facial-face or human-face interaction, if possible. “

The study also did not report leaks from masks, whether worn properly or inappropriately, that could increase the number of droplets making their way into the air.

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The article, “Can face masks offer protection from airborne sneezes and cough drops in close, face-to-face human interactions? A quantitative study,” written by Krishna Kota, Javed Akhtar, Abner Luna Garcia, Leonardo Saenz, Sarada Kuravi, and Fangjun Shu. The article will appear in Physics of wetness on December 22, 2020 (DOI: 10.1063 / 5.0035072). After that date, it can be accessed at https: //aip.scitation.org /doi /10.1063 /5.0035072.

Physics of wetness dedicated to the publication of original theoretical, computational, and experimental contributions in the dinamics of gases, liquids, and complex or heterogeneous liquids. See https: //aip.scitation.org /magazine /phf.