I meant 3x. Coronavirus can go through N95 filter size, but just as mention in the link below, that’s still better than not using it. For certain situations, like needing to go out for errands and then be near the elderly, it’s smart to have it and makes sense for individuals to buy the retail stock.

https://www.wired.com/story/coronavirus-interview-larry-bril...

3x sounds more likely than x1/3.

The thing is that even if it is bigger than virus it still stops part of it.

Especially if it is true that virus is is not airborne and spreads through droplets.

In that case even scarf might be better than nothing (you should wash it often though).

Don't think so. GP acknowledges that it'll still let the virus in, but at a lower rate than someone without a mask at all.