Canvas masks do little to prevent the spread of COVID-19or other airborne diseases, a new study has found.
Researchers at the University of Bristol in the United Kingdom have found that 90 percent of the particles can pass through cloth masks, making them effectively useless during a pandemic.
Canvas masks are popular in the United States because they are easy to reuse after washing and at times were the most affordable due to shortages and high prices for surgical or N95 masks.
However, experts have now found that these masks do almost nothing to stop the virus from spreading, and may have contributed to the spread, as people who believe they are safe do not.
Researchers have found that canvas masks block only about 10 percent of all particles from penetrating. Because cloth masks are made of densely woven yarn (top), unlike surgical and other types of masks that are made to filter particles (bottom), they are less protective against Covid
Researchers also do not recommend surgical masks because they do not fit well and often leave gaps that allow filtered particles to escape.
Researchers who published their findings on Tuesday in Fluid physicsbuild a simulation of airflow using 3D images to assess how well the different masks were used during the pandemic, filtered particles.
They note that unlike N95 or surgical masks, cloth masks are not made of a material made to filter particles.
Canvas masks are made of densely woven fabrics. Although not visible to the eye, small gaps in the tissue are enough to allow the vast majority of particles to pass.
“Masks are air filters, and fabrics like cotton make good jeans, shirts and other clothing, but they are bad air filters,” said Richard Sear, co-author of the study and a physicist at the University of Surrey. declaration.
KN95 masks are designed for particle filtration and have a standard filtration of 95 percent.
“The filter layer of the N95 mask is made of much smaller, 5-micrometer fibers with gaps that are 10 times smaller, making it much better for filtering out nasty air particles, such as those containing a virus.” said Sear.
KF-94 masks are also considered very effective, with the ability to filter 94 percent of the particles.
However, filtering efficiency is not the only two advantages of these masks. Fitting is also very important.
The sign should fit snugly around a person’s face, almost hugging his nose, cheeks and chin.
This is to avoid leaving gaps above or below the mouth and nose where air can escape.
Even if a person has a mask that can filter up to 95 percent of the particles, if the mask does not fit well, then the particles can simply escape from the side.
That is why Sear also does not recommend the use of surgical masks.
“Surgical masks do not fit well, so a lot of air passes unfiltered along the edges of the mask to the cheeks and nose,” he said.
Although this is only a computer-based study, the consequences are great when we look back two years from the COVID-19 pandemic.
Many Americans wore cloth masks, almost exclusively, during the pandemic, believing they were doing their part to stop the virus from spreading.
Wearing a mask may also have made people feel more comfortable going out in public, believing that face shields will protect everyone around them from the virus.
Cloth masks may provide little or no protection, and people who believe they are taking appropriate measures to mitigate the virus do not.
Centers for Disease Control and Prevention recommends KN95 masks as the gold standard to stop the spread, but still recommends cloth masks as a valid front cover on your website.