RALEIGH, N.C. — Mask mandates are being gradually being lifted, but a team of researchers at North Carolina State University remain curious about face covering effectiveness and are continuing to test performance inside a specially made lab.  

 

What You Need To Know 

N.C. State Wilson College of Textiles tested the quality of certain masks against COVID-19 during the pandemic 

Bryan Ormond, Ph.D., looks at filtration efficiency, breath ability and fit 

Researchers break down the differences in types of PPE such as the N95s, KN95s and KF94s 

 

Bryan Ormond, Ph.D., is an assistant professor at the North Carolina State University Wilson College of Textiles. On the third floor in a confined space, he and his assistant Melissa Armistead are evaluating the quality of face coverings using an animatronic head.

"Textiles are in everything. I don’t think people realize how significant they would be in these face coverings,” Armistead said, who is a Ph.D. candidate.

The synthetic motorized head the researchers are working with is a replica of what you might find on a Hollywood set for costume design. Their experimentation simulates a mask’s ability to filter particles inside a contained, translucent chamber.

Armistead said the goal of the test is determining how well the masks can be used as filters. 

“Just working on face coverings, something that we have to wear every single day, was really interesting. To study how the different impacts of fit and design really change the filtration efficiency and the performance of them as a system, instead of just a material level test,”  Armistead said.

When the pandemic began, Ormond said he pivoted from testing occupational textiles to researching how well certain types of masks protect a person from COVID-19.

Before the virus outbreak, respiratory protection was mostly an occupational concern for industrial jobs and the medical field. The N.C. State professor said the novel coronavirus changed that.

“For the general public, they want one answer to start with, and that’s been really hard over the last two years because we have been learning and adjusting the entire way,” he said.

There may be no topic more discussed than masks during this pandemic. They are studying the effectiveness of N95s, KN95s, and KF94s–along with other facial coverings. For example, one difference between N95s and KN95s is how the masks conform to your head. The N95s use head straps and are approved by the National Institute for Occupational Safety and Health (NIOSH), whereas KN95s use ear loops and are not. 

Another distinction is the country of origin. The KF94s are regulated by South Korea’s Ministry of Food and Drug Safety. The standard of approval meets a similar threshold as the performance requirements for the N95 masks to be certified in America.

There’s a human factor to this equation as well.

“If it isn’t comfortable, people aren’t going to wear it,” Ormond said. 

Ormond said their tests measure a mask’s ability to block droplets or particles called aerosols, its breath ability and fit to a human face.

Their simulations detect the size and types of those aerosols, some of which may carry COVID-19.

"When we test on an actual head form, you get to see the fit and seal of your face. The face is not a flat thing. This gives us a more realistic evaluation," Ormond said. 

Their work showed them where air can leak on the face around the nose and bridge of the chin.

"What we are doing is not just looking at ideally how well a material could work, but when you put it on a face you can actually see the leakage, you can see the areas where you are not getting the same level of protection you could ideally get," Ormond said.