...wear a KN95 mask ( FDA approved ), you keep out 95% of small... a single layer cotton mask , it's virtually worthless for everyone. About 4... masks or a mask and face shield will be better...
5 Answers · Health · 14/11/2020
...get a KN95 mask ( FDA Approved , well fitting... or wear 2 masks or a mask and a face shield. Although... are for people over age 80 and 37...
3 Answers · Health · 07/11/2020