Referring you to the link in my reply 12.
See anything grossly wrong with it?
I’m not a fan of masking but try to be fair on data.
Personal opinion on that particular link... HEPA filters are great and work fine in specific areas I. e. closed or sealed rooms and they are used in labs but using one in a restaurant or anything like it is useless. You put the filter on the intake system, clean air comes out but that doesn’t account for all the air in the room, doors opening a d people exhaling any airborne particles. If I had covid and exhaled into the HEPA filter when the air system is on then fine... point being the system would need to be on 24/7 to work on the guy exhaling into it.
Mask weren’t designed for stopping this type of disease period. Mask worn often and for extended periods cause respiratory issues, covid is a respiratory disease.... think about that.
Social distancing has always been a joke in public places.