Research has shown that wearing only a mask without distancing may not be enough to block COVID-19.
In particular, cloth masks have been shown to require a distance for yourself or your opponent.
According to the American Institute of Physical Sciences (AIP), the research team, including Associate Professor Krishna Kota, at New Mexico State University, participated by experimenting with the effect of blocking droplets that carry the corona 19 virus when coughing or sneezing on five masks. Published in'Physics of Fluids'.
Each mask drastically reduced the spread of droplets, but it was found that within a distance of 1.8 m, some of the materials escaped the droplets that could cause Corona 19 infection.
"It is clear that a mask is helpful, but there is still a risk of spreading or infecting the Corona 19 virus when a person is close," said Associate Professor Kota. "It is necessary to wear a mask and keep physical distance together." I did.
The research team created an experimental device capable of filming the process by blowing small liquid particles such as droplets with an air generator into a sealed square tube equipped with a laser sheet to produce an effect such as coughing or sneezing.
The research team equipped this square tube with a double cloth mask, PM 2.5 dry, wet filter-mounted double cloth mask, surgical mask, and health N-95 mask.
As a result, the N-95 mask statistically blocked 100% of the droplets, but all other masks slightly passed through.
In particular, in the case of a simple double cloth mask, it was found that the amount of droplet passing through it reached 3.6%.
It has been pointed out that within 1.8m distance, a person infected with Corona 19 can infect someone when they cough or sneeze multiple times.
After the N-95 mask, the PM 2.5 wet filter-equipped double cloth mask had the lowest droplet penetration rate at 0.03%, followed by a surgical mask (0.06%) and a dry filter-equipped double cloth mask (1.70%).
The researchers say that although it depends on the condition of a patient with Corona 19, 200 million virus particles are released per sneeze, and that even if the mask filters out a significant portion, enough of the virus can escape to infect people in close proximity.
"Wearing a mask actually protects people who are susceptible to infection by reducing the droplets of coughing and sneezing, but it's not perfect," said Associate Professor Kota. .
The results of this study pointed out that physical distancing is necessary regardless of the mask material because the variable that the droplet escapes to the edge of the mask due to improper wearing of the mask is not considered.
(Photo Credit=Javed Akhtar, Yonhap News)