The agency cites research done at UW-Madison that found that when the Badger Seal – a mask fitter that was developed by UW-Madison engineers – was put over a three-ply mask, it reduced the amount of particles able to enter by 15 times.
The agency cites research done at UW-Madison that found that when the Badger Seal – a mask fitter that was developed by UW-Madison engineers – was put over a three-ply mask, it reduced the amount of particles able to enter by 15 times.