Transcript for Mask wearing fit and placement and its effectiveness to stop the spread of COVID-19
Back now with that ABC news exclusive showing just how effective masks can be at helping stop the spread of the coronavirus and helping save live, but only if worn the right way. With the virus raging again in millions of Americans on the move this holiday weekend erielle reshef is here with this important reminder. Good morning to you, erielle. Reporter: Hey, good morning to you, Eva. We all know the CDC recommends wearing a mask as the first line of defense against the virus. But experts say it's how you wear your mask and which one you choose that can make all the difference. For instance, wearing that mask under your nose or picking a mask T too big just won't cut it. This morning, exclusive demonstrations showing how fit and placement are crucial when wearing a mask. "Gma investigates" teaming up with engineers at Florida atlantic university to find out where particles escape on loose fitting masks and why those who don't cover their nose, half maskers, are not protecting anyone including themselves. First up the popular blue surgical mask using a mannequin that can simulate a cough or sneeze by releasing liquid particles researchers loosely placing it on the mannequin's face. We noticed there were droplets escaping primarily from the gap along the top edge of the mask. Reporter: Now look after pushing that metal strip down around the nose to seal that gap, fewer particles escapeing there but an increase in particles leaking from the sides of the mask by the cheeks. But overall a significant reduction. Any metallic wires or strips that are present, you should always try to press it down. Reporter: Watch what happens when a mask does not cover the nose. What's called half masking. We see droplets escaping from everywhere. When you're half masking, you're keeping your nose exposed which makes it easier for the virus particles to enter. Reporter: See the difference in escaping particles wearing a mask properly versus half masking. Now the homemade cotton mask made with multiple layers but this one without a metal strip. A surprising reveal of where the particles escape. They usually start moving backward behind the person who is wearing the mask. Reporter: Researchers say the particles can easily get carried around depending on airflow conditions. That's why it's important to practice social distance, even when wearing masks. The mask with the least escape of particle, n-95. The gold standard for health care professionals. Health care professionals go through a fitting process so it fits the face most effectively. Reporter: The researchers say these masks have a heavier metal strip that closes any gaps. It reinforces how important it is to wear masks appropriately and to cover your mouth and your nose. Reporter: Even though the n95 mask performed the best experts say to leave those for health care professionals exclusively. As for the public we should be wearing fabric mask as cording to the CDC with at least two layers preferably with one of the metal nose trips. We've been wearing masks for months now so at what point should we be looking to replace those masks? Reporter: Eva, experts say if you can see light through your mask simply not working for you, also'elastic seems to be wearing out and getting too big you need to replace it. If the edges are fraying it's probably not working. Eva. Lots of good tips for us, erielle, thank you.
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