A Duke University study with 14 different types of face masks by scientists has yielded some surprising findings about the effectiveness of different face masks, while also underlining the claim that each mask or face mask is better than none.
In a test, researchers found that talking in some masks, in particular a neck fleece or bow tie often worn by runners, actually spread the largest drops of potential virus into small drops. The study examined the extent to which masks block drops to enter the air, net or the mask drops successfully blocked to enter the mask wearer’s mouth.
“Considering that smaller particles carry air longer than large droplets (larger droplets sink faster), the use of such a mask can be counterproductive,” researchers wrote in the study, which was published Friday in Science Advances.
Overall, a fit N95 paired with a surgical mask for best performance in terms of minimizing the number of droplets spewing into the air. In fact, it was a three-layer surgical mask, which for some may look bleak, was about as good as the N95, which is considered by many to be the gold standard of face masks. Depending on the type of material, cotton masks are also properly tested.
14 different face masks studied by Duke University researchers.
Science Advances
Knitted masks and bandanas performed the worst. Fleece masks, as mentioned above, were considered worse than removing any mask.
Overall, it turned out that the fit of a mask was also very important. A so-called valved N95 mask was significantly smaller than a fit N95.
The new study comes as the pandemic has a new industry of washable cloth and face mask designer. Since the end of April, New York City has been distributing free surgical face masks to New Yorkers at various locations, including city parks. In line with guidance from the Centers for Disease Control and Prevention, Mayor Bill de Blasio has suggested that scarves or homemade dust masks can be worn instead of a surgical mask, which can be easily contaminated. Although some health authorities advise against reusing surgical masks, Blasio has said the masks can be washed and reused.
In an interview with the Boston Globe, Warren Warren, a professor of physics, chemistry, and radiology who was one of the co-authors of the study, said individuals should study the material of a face mask. “If you have a mask and you can see through the light and you can blow through it, it’s probably not a very good mask,” he said.
Public health experts have said that face masks can significantly reduce the spread of the virus. Members of the White House coronavirus task force have been begging Americans in recent weeks to carry them, especially in parts of the country where the virus grows. However, President Donald Trump has rarely worn a mask in public.
One new model has projected that 66,000 American lives could be saved if 95% of all Americans complied with the face mask recommendation. At least 163,000 people in the country have died from coronavirus. Scientists at the University of Washington expect that number to die by December to nearly 300,000.
