I found this article when looking up the what the deal is with microns and masks. The net net is that mask is better than no mask. How much for how long and what percentage etcetera is in the link below.
So I bought in early March when all the lockdowns started the O2Canada Mask… I had shipped the handful of N95 masks off to my cousins in NYC. I have neck buffs but wasn’t sure how well that would do, when I ordered it was the only place that would let me order anything. I googled for hours one night.
I’m sure there are other solutions out there that will be available, but this works well and covers mouth and nose and has a silicon gasket and when I run it stays in place.