Trust Index: Valve masks do not stop spread of COVID-19, only ventilates one way

Experts say air filters when you breathe in, not when you breathe out

Trust Index: Valve masks do not stop the spread of COVID-19, only ventilate one way

SAN ANTONIO – Valve masks became popular toward the beginning of the COVID-19 pandemic response, but people are now being told not to use them.

Wearing masks can be annoying, which is why people began turning to valve masks that have circular or square vents that allow for more comfortable breathing.

But as COVID-19 cases across the United States continue to spike out of control, comfort takes a back seat.

Experts across the globe say valve masks only filter the air you breathe in, not the air you breathe out, which means if you have COVID-19 you could still spread it to others.

“If I were to have COVID and not know it, I don’t want to spread that to other people, so in the hospital setting it makes sense to have N95 that offers basically that two way protection,” said Dr. Robert Frolichstein, who works in local emergency rooms and is president of the Greater San Antonio Emergency Physicals.

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Frolichstein said he and his colleagues use normal N95 masks but never the ones with valves.

“There are certainly N95 masks that are only designed to breathe in. Those are typically used by industrial workers. The people that are cutting tile, cutting stone. They’re not designed to prevent exhaling potentially COVID-containing droplets,” Frolichstein said.

So when people say valve masks offer two-way protection and are the best defense against COVID-19, that is false on our KSAT Trust Index.

As experts have continued to tell KSAT, the best option for the typical person is a cloth mask, preferably with two or more layers of material.

“With the exception of health professionals who are spending large amounts of time extremely close to people we know have COVID-19, the idea of wearing a cloth face covering is just a great common sense an an extremely humanitarian thing to do,” said Dr. Fred Campbell, UT Health San Antonio associate professor of medicine.

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Campbell said protecting the entire community to stop the spread of COVID-19 goes two ways, not one.

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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.