I work in a mall where I see lots of families with kids who don't speak a lick of English. CDC says we're seeing maybe a dozen diseases the last couple years which were previously considered eradicated here decades ago or were unknown here. Also the mall is not cleaned well and I'm allergic to house dust. Therefore I wear a KN95 when at work, but nowhere else.
They may have some value in other types of illnesses - especially bacterial. But shown not to work on respiratory viruses at all.
I work in a mall where I see lots of families with kids who don't speak a lick of English. CDC says we're seeing maybe a dozen diseases the last couple years which were previously considered eradicated here decades ago or were unknown here. Also the mall is not cleaned well and I'm allergic to house dust. Therefore I wear a KN95 when at work, but nowhere else.