What does the current research say re: using a kn95 for how many hours?
I am not rich so I need to get max use from my kn95 masks. Curious if there has been some recent data regarding how many hours ( or days or events) one may wear the same mask.
I am not rich so I need to get max use from my kn95 masks. Curious if there has been some recent data regarding how many hours ( or days or events) one may wear the same mask.