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This Face Mask is Worse Than No Face Mask, Study Shows

The scientists compared 14 different kinds of masks in their study.
Face masks

Health officials have long advised that wearing a face covering—any kind of face covering—is helpful for slowing spread of coronavirus. But one kind of face mask is less effective than the rest and might actually promote spread of the disease, say researchers at Duke University.

The scientists compared 14 different kinds of masks in their study, which used laser light to visualize how well respiratory droplets passed through different fabrics when volunteers spoke a short phrase. It's believed those droplets—spread from the nose and mouth—are the primary way people are infected with coronavirus.

"We confirmed that when people speak, small droplets get expelled, so disease can be spread by talking, without coughing or sneezing," said lead researcher Martin Fischer. "We could also see that some face coverings performed much better than others in blocking expelled particles."

RELATED: Your Face Mask Protects You in More Ways Than One, Study Finds

Coming in at No. 1: Fitted N95 masks, which blocked the most respiratory droplets, followed by surgical masks and masks made of polypropylene, a fibrous type of plastic used in fabrics.

Worse than wearing nothing

The worst performer: A neck fleece, which researchers found was actually worse than wearing no face covering at all.

Why? The neck fleece tested seemed to actually create more droplets by breaking large ones into pieces.

"Common sense would dictate that wearing anything is better than wearing nothing – this was not the case here," said Fisher. "We observed that the number of droplets increased when the speaker put on the neck fleece. We believe that the material of our fleece breaks down large droplets emitted during speaking into several smaller ones. This could make wearing such a mask counterproductive, since smaller droplets have an easier time being carried away by air currents and endangering nearby persons."

Keep masking up

More research is definitely needed: It's unclear whether it's the material of the specific fleece tested—or the structure of a fleece itself, which around your head like a tube top for your face—caused this droplet-proliferation effect. (And the Duke researchers said they were primarily studying the laser device, not which mask fabrics are best.)

In the meantime, mask up—but it's a good idea to research the types of facial coverings you use.

And to get through this pandemic at your healthiest, don't miss these Things You Should Never Do During the Coronavirus Pandemic.

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