It’s all about size! Why experts say it’s false to say masks don’t filter out coronavirus because odors can get in

We ran the claim circulating online through our KSAT Trust Index

It’s all about size! Why experts say it’s false to say masks don’t filter out coronavirus because odors can get in. (KSAT 2020)

SAN ANTONIO – Mask effectiveness is spurring all kinds of conversations nationwide and even causing some controversy.

Some posts circulating online are claiming that since you can smell things like food or smoke through a cloth mask, the covering will not filter the coronavirus. We ran it through our KSAT Trust Index, and experts say that's false.

The reason has to do with the size of certain particles.

"The particles that cause odors, these are extremely tiny molecules. Although the COVID-19 virus is a microscopic microorganism, it still is much, much more complex than the molecules that would cause odors to be smelled," said Dr. Fred Campbell, associate professor of medicine at UT Health San Antonio.

"In fact, there is no way you can prevent an odor coming into your nose unless you weren't able to breathe," he said.

With that said, no mask is proven to keep the coronavirus out 100% of the time. That's why Campbell says the way you use your mask is very important.

The public is being asked not to use N95 masks so they can be saved for medical professionals who work directly with COVID-19 patients in extremely close settings. With the recent surge in cases, Campbell says that's more important now than ever.

When it comes to masks for the everyday person, experts recommend cloth coverings with as many layers as possible.

“Any mask or face covering with greater than two layers is going to reduce the chance of transmitting COVID-19 at least by half if not more,” Campbell said.

He recommends finding the cloth masks with an opening in the middle of two layers. An additional filter or piece of material can be put in there to strengthen the mask.

People are using all kinds of materials for those filters within cloth masks, but Campbell says the one he's found to work the best is surprising to some people -- denim.

So it may be time to cut up those old jeans you keep in the back of your closet!

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About the Author:

Courtney Friedman is a KSAT anchor and reporter. She has an ongoing series called Loving in Fear, confronting Bexar County’s domestic violence epidemic. She's also covered Hurricane Harvey, the shootings in Sutherland Springs and Santa Fe, and tornadoes throughout Texas. She’s a California native and proud Longhorn who loves calling SA home.