Masks! What Works, What Doesn’t and Covid-19 Stopping Masks
Dr. Robert R. Redfield, director of the Centers for Disease Control and Prevention (CDC) calls cloth face coverings one of the most “powerful weapons we have to slow and stop the spread of the virus.”
According to the CDC, the coronavirus is primarily transmitted when a person infected with COVID-19 releases respiratory droplets by sneezing, coughing or talking. The infectious droplets can land in the mouths or noses of people standing nearby or possibly inhaled into the person’s lungs.
So wearing a face mask or cloth face-covering in public goes a long way in protecting against the virus. But, not all face coverings are effective in blocking infectious droplets. So, what type of face mask can best protect against COVID-19? Let’s take a look at which products work and don’t work against the virus.
Which Masks Works:
1. TrioMed Active Mask
A Canadian-based manufacturing company created the first-of-its-kind face mask that can deactivate more than 99 percent of SARS-CoV-2 (CoV-2), the virus that causes COVID-19, in a matter of minutes.
A team of scientists at the University of Toronto’s (U-T) Department of Molecular Genetics, tested the coating on the TrioMed Active mask manufactured by i3Biomedical Inc. in Quebec. Patient samples of CoV-2 were applied to the mask’s antimicrobial coating. In repeated tests, researchers “could not recover” any of the CoV-2 virus from the mask.
U-T’s Professor Scott Gray-Owen, who led the research team, said i3 Biomedical Inc. had a breakthrough in discovering how to bring the chemicals directly to the surface of the mask material.
2. N95 Masks
N95 masks, also known as medical respirators, are among the most effective face coverings that protect against COVID-19. The reason? The mask fits closely to the face and forms a seal around the nose and mouth. What’s more, the tight-fitting mask filters out at least 95 percent of large and small airborne particles, according to the CDC.
The CDC, however, does not recommend that the general public wear N95 masks, but reserve them for healthcare workers and first responders who need protection from airborne particles and splashes, sprays, and other fluid hazards.
3. Surgical Masks
Surgical masks, usually worn by healthcare professionals, work well against COVID-19. A surgical mask, made of non-woven fabric, is loose-fitting and blocks out large-particle droplets, splashes or sprays that contain viruses or bacteria. This prevents germs from reaching the wearer’s mouth and nose.
Unlike the N95 masks, a surgical mask does not prevent the wearer from inhaling small particles in the air transmitted when someone coughs or sneezes or during certain medical procedures, according to the CDC.
4. Cotton-Blended Masks With Filters
Whether manufactured by a company or made by hand, studies show that masks made of 100-percent cotton combined with other fabrics are more comfortable, breathable, and effective in preventing exposure to viruses.
According to Taher Saif, a professor of mechanical science and engineering at the University of Illinois (U-I), breathable fabrics tend to resist droplets released when a person coughs or sneezes. Saif led a U-I research team that tested cotton, polyester, and silk, and their effectiveness in resisting droplets.
U-I researchers found that the household fabrics, when used in two layers, effectively blocked 98 percent of droplets, which is more than a medical mask blocks and is more breathable. Saif explained that common household fabrics soak up water so they are able to retain droplets whereas medical masks repel water.
Researchers in the United Kingdom conducted similar tests on masks that combined cotton with silk, chiffon, flannel, and various synthetics.
The study found that the best-performing mask was made of two layers of 600-thread count cotton combined with silk, or flannel, or chiffon. The “hybrid” mask, as researchers called it, filtered more than 80 percent of small particles and 90 percent of larger particles.
With homemade masks, health experts recommend sewing a pocket in a two-layer cotton mask and inserting a filter made of polypropylene fabric, which can be purchased at local stores or ordered online.
According to May Chu, an epidemiologist at the Colorado School of Public Health and a scientific adviser to the World Health Organization, polypropylene works well because it holds static electricity. Chu explained that the static “cling” effect works by trapping incoming and outgoing droplets. What’s more, polypropylene maintains its electrostatic charge in the humidity produced when the mask wearer exhales.
If polypropylene material isn’t available, then Chu suggests folding over two sheets of facial tissue and placing them inside the pocket of the mask. Although the four layers of tissue offer added protection, it doesn’t have the added power as an electrostatic charge, Chu said.
What Masks Don’t Work:
1. Masks With One-Way Valves
Masks with one-way valves or vents are more comfortable to wear because they allow air that the wearer exhales to pass through holes in the material. These products, however, get a thumbs down from the CDC because the masks allow unfiltered exhaled respiratory droplets to reach other people. So, a person infected with COVID-19 wearing a mask with a valve can potentially transmit the virus to others.
2. Bandanas and Neck Gaiters
Bandanas and neck gaiters provide some form of protection, but studies are showing that they are not even as effective as homemade cotton masks. A neck gaiter is a tube of fabric that slips over the head and covers the wearer’s nose and mouth. Some people chose to wear a neck fleece, also called a ski mask, which has openings for the eye, nose, and mouth.
Scientists at Florida Atlantic University tested a variety of non-medical masks available to the general public to determine their effectiveness in blocking respiratory droplets. Results showed that loosely folded face masks and bandana-style coverings reduced droplets spread to some degree, but well-fitted masks with many layers and cone styles were better at blocking the droplets.
In a similar study, researchers at Duke University found that bandanas and neck fleece offered very little protection in blocking respiratory droplets. The study was published on August 7 in Science Advance.
Dr. Eric Westman, a Duke physician who participated in the research, said it’s important for the public and companies supplying masks to employees to have good information on which products provide the best protection.
“If everyone wore a mask, we could stop up to 99 percent of these droplets before they reach someone else,” Westman said in a news release about the study. “In the absence of a vaccine or antiviral medicine, it’s the one proven way to protect others as well as yourself.”