Washington
As newer, more portable versions of the coronavirus spread, experts say it’s time to consider using a medical-grade respirator, or wearing a surgical mask. and linen together.
Scientists have long agreed that it is the main way of spreading the virus through the air, rather than on the surface, and there is growing evidence that small drops from normal breath and speech can travel many meters as a means. common distribution.
In addition to this, there is a greater susceptibility of emerging mutations, such as B.1.1.7, which gives a smaller viral load to induce a typical Covid-19 compared to the most common snoring. common.
Fit and filtration
Back when authorities first recommended people to wear face masks, proper masks were in short supply and the public was encouraged to make portable solutions out of T-shirts or bandanas. But these are far from ideal.
Linsey Marr, professor of civil and environmental engineering at Virginia Tech, which studies the spread of airborne disease, said AFP: “How well a mask works depends on two things: filtration and fit.”
“Good filtration removes as many particles as possible, and good conditioning means there is no leakage around the sides of your mask, through which air – and viruses – can pass,” she said, adding. even a small gap that could lead to its 50 percent Decrease in performance.
The best materials for preventing small particles include non-woven polypropylene, which is used to make N95s and many surgical type masks, and the HEPA filters in planes. Among clothing, tight-knit cotton works best, she said.
Doubling
“If you’re wearing a cloth mask, choose one that has several layers, especially one with a pocket that you can slip in a good filter material,” Marr said. “Or you can double up a mask by wearing a surgery-type mask with a tight-fitting cloth mask attached over it.”
Surgical masks are made of a material that filters things out well, but they tend to be loose, so putting a cloth mask on top keeps the edges down and reducing leakage.
Adding an extra coating improves seeding – if one layer captures 50 percent of all grains, two combinations get up to 75 percent.
However, she said: “We do not recommend wearing more than two masks. Applying more layers ensures a reduced yield and can breathe. It needs to stay easy to breathe. take it through the layers; otherwise, air is more likely to let in around the sides of the mask. “
Masks that have a metal nose bridge help ensure proper snugness, as do straps that tighten around the head, not just the ears. Sewers that improve the suitability of surgeries are now available in the market.
“You should feel the mask flush in when you breathe in, and if you keep your hands around the sides of the mask, you should not feel any air leaking out when you breathe out, “said Marr.
Medical grade reliefs
Another option is to grab N95s, or international ones like KN95, FFP2 etc.
“They all provide the same level of filtration, meaning protection from grains going in and out,” said Ranu Dhillon, a global health physician at Brigham and Women’s Hospital and Harvard Medical School.
Dhillon, who has been advocating for better masks since last spring, is plagued by the lack of clear messages to the public about the value of better masks.
Moreover, “no strenuous effort has been made to mass-produce and mass-produce these high-quality masks.”
Healthcare workers have their masks professionally tested every year to make sure they’re making the right seal, but Dhillon doesn’t see this as a major hurdle.
“Teaching people to apply a mask, even if it’s not 100 percent perfect, but more effective, is something that is very impossible.”
Masks in our future?
The way to conceptualize the risk is to think about cigarette smoke, said Donald Milton, a professor of environmental health at the University of Maryland.
Ventilation will certainly help, but if you’re between a breather and an air shower, the virus will still reach you – which makes good masks so essential, he said.
Milton and Dhillon are hopeful that their protests could become a policy administered by President Joe Biden, and CNN reported last week the U.S. government was working on the first official standards on a mask.
Before the pandemic, Milton and other aerosol scientists who studied the flu concluded that it is also transmitted from tiny droplets from normal talking and breathing, and that the task of sneezing, coughing and sneezing from the surface was less than expected.
Their decisions raised controversy at the time, but Covid-19 has rekindled interest in the research – meaning masks could become a common sight during the flu seasons, long after the flu transmission of pandemic disease.