Neck gaiters can not protect people amid COVID-19, say Duke University researchers

Washington [US], Aug 12 : Amid the coronavirus pandemic face masks have become part of everyone's lives but there are questions on which masks to wear. Researchers from Duke University have recently published the results of its study that tested which face covering is effective to prevent the release of droplets.
"Cloth face coverings are one of the most powerful weapons we have to slow and stop the spread of the virus - particularly when used universally within a community setting," The Washington Post quoted Robert R. Redfield, director of the Centers for Disease Control and Prevention, as saying.
The Washington Post reported that the researchers unveiled a simple method to evaluate the effectiveness of various types of masks, analysing more than a dozen different facial coverings ranging from hospital-grade N95 respirators to bandanas.
To test the masks, The Washington Post reported that Martin Fischer, a chemist and physicist in the University's physics department, has created a device that allowed his team to track individual particles released from a person's mouth when they are speaking. Besides, a box made of cardboard and a lens was used in the test process.
"It's very straightforward, doesn't take much resources," Fischer was quoted as saying in a video produced by Duke. "Any research lab has these things lying around."
The speakers were asked to say a phrase in the box while wearing a face mask and again without wearing the mask. Each mask was tested 10 times. The Washington Post stated that inside the device, the airborne particles passed through a sheet of light created by the laser hitting the lens and produced visible flashes that were recorded by the phone's camera.
After studying about 14 face masks and other coverings the researchers found that cotton cloths are as much effective as a standard surgical mask but neck gaiters made of thin, stretchy material are not effective.
"These neck gaiters are extremely common in a lot of places because they're very convenient to wear. But the exact reason why they're so convenient, which is that they don't restrict air, is the reason why they're not doing much of a job helping people," Fischer said.
According to Fischer, high droplet count was observed during the tests. "It's not the case that any mask is better than nothing," he said. "There are some masks that actually hurt rather than do good."
One of the study's co-authors, Warren S. Warren, a professor of physics, chemistry, radiology and biomedical engineering at Duke, was quoted as saying, "Those relief valves are fantastic if what you want to do is protect yourself from the outside world because air doesn't come in through them. "If what you're trying to do in this pandemic is to protect the outside world from you, it completely defeats the purpose."
Though the study was not a clinical trial, the general conclusions drawn from the tests are factually correct, he said.
"We're very careful not to over-claim here," he said. "We are not going to try to say our evidence is that this is the thread count you should use on the sheet for the two-ply cotton mask that you're making.
"But the broad take-home picture -- that masks do work in cutting down transmission and that some masks that you can easily get are better than others -- potentially has value in protecting everybody and getting us out of this awful situation," he added.
The research team is currently planning to produce a step-by-step instruction guide to create a testing device.
He said that not all people can construct a device as "a modest amount of scientific training" is needed "to use this quite safely and quite effectively."
"The idea is that you could have community centres, groups that are helping to test out different designs. Particularly as we're trying to provide face masks to a large number of people who don't have them, you want to be providing ones that work."