Dear Marin,

Whenever I go out and about, I make sure to wear my face mask. Like you, I wanted to find out exactly how they work.

First, I talked to Marian Wilson, an assistant professor and nurse at Washington State University who is curious about how face masks protect people.

“When we talk, sneeze, sing, or laugh, we spread droplets into the air all the time,” she said. “With the COVID-19 pandemic going on, we know people may have virus in their droplets.”

Those droplets come from saliva—your spit—or mucus and can infect others and make them sick. But masks can help you keep your droplets to yourself.

Marian Wilson, an assistant professor of nursing at WSU.

When you wear a mask, you are also protecting your own mucous membranes. That is, the lining inside your nose, mouth, and throat where germs can enter the body.

My friend Hang Liu, an assistant professor and materials scientist at WSU, reminded me masks are made of different materials. A lot of reusable cloth masks are made up of tiny fibers, such as cotton from plants.

If we looked at a cotton mask under a microscope, we would see the tiny fibers woven closely together.

The fibers leave very little space for things like tiny droplets to get through. In a way, the material’s fibers create a kind of obstacle course for the germs—especially if there is more than one layer of fabric.

Another kind of mask is one doctors and nurses need for work. These N-95 masks create an extra tricky obstacle course for droplets that might carry the virus.

Liu said these masks are made of three layers. The middle is made of submicron fibers, which create teeny tiny pores that can even block out really small droplets. There’s also another interesting feature.

Hang Liu, a materials scientist at WSU.

“When these fibers are produced, they are electrically charged, so the charges can actually attract germs and allow them to stick on the fibers,” Liu said.

We know from research that masks work, Liu and Wilson said. Masks have been used in lots of countries and throughout many pandemics.

Dr. Universe cartoon cat character looking up to the sky

With the novel coronavirus, a person may not always look or feel sick. That’s why it is so important for people to properly wear a mask even if they aren’t showing symptoms. It reduces the chances of getting sick or infecting others.

Wilson and her team have developed and tested a new kind of mask. The mask is re-usable and could be used by healthcare workers if they do not have access to N-95 masks.

“We wanted to create something healthcare workers can use in a pinch if they didn’t have high quality medical masks they needed,” she said.

Now she is wondering how to make masks even better to help in the pandemic. One way you can help reduce the number of people who get sick is to wear a mask. Always leave at least six feet between you and people who do not live in your household, too. Together, we can help keep each other safe and healthy.

Dr. Universe



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