Bandannas, gallstones and knitted masks are some of the most ineffective ways to stop the spread of coronavirus, according to a new study.
Researchers at Duke University made the discovery while testing 14 different types of masks, according to research published Friday.
N95 masks, commonly used by health care professionals, work best to prevent the transmission of airway drops during normal speech.
Duke researchers found that other good performers at preventing leaks are three-ply surgical masks and cotton masks, which can be made at home.
However, while knitted headbands and veils may be a unique look, they do not offer much protection, according to research.
Scientists also found that scarves, or collars, often worn by runners, were least effective and actually allowed more drops of the airway to escape than not wearing the aperture. Page.
That̵7;s because they have been shown to break larger droplets into smaller particles, allowing them to slide off the sides of the coating more easily.
Martin Fischer, one of the authors of the study told CNN: “We were surprised to find that the number of particles measured in wool actually exceeded the number of particles measured without wearing any face. any mask.
“We want to emphasize that we really encourage people to wear masks, but we want them to wear masks that really work.”
To test the mask, the scientists used a black box equipped with a laser and a mobile phone camera.
Someone wearing a mask will speak in the direction of the laser beam inside the box. Then, the amount of respiratory droplets that were scattered along the beam was recorded by the camera at the back of the box.
Then, a computer algorithm counts the drops seen in the video to determine how many drops have leaked.
Researchers say this is an effective, low-cost way to test which face masks are effective and which are not.
“This is a very powerful visualization tool for raising awareness that a very simple mask, like this homemade cotton mask, is actually effective at suppressing most sugar drops,” Fischer told CNN. this respiration.
“Companies and manufacturers can set up and test their mask designs before production, which would also be very helpful.”