Adidas makes some very lightweight mesh fabrics for sports shirts. The downside of these fabrics is that they aren’t very durable, and tend to wear out in a couple years. The upside is… well, you can use a worn out shirt to make multiple low-restriction face masks for exercise.
As a lot of people are finding out, a decent hospital filter mask restricts air flow too much for aerobic activities. Huffing and puffing through a fine cotton fabric can be a very uncomfortable experience. Luckily, avoiding sending flecks of spittle into the air does not really require a fine mesh filter. Thus, the quick drying, lightweight, stretchable fabric of my old Adidas tennis shirt appears almost perfect for a casual outdoor filter mask.
First, I scissored off both short sleeves. Each one stretched easily over my head, so all they needed was a bit of trimming to give my ears a little air. I was going to stop there (how many would I need?), but then I noticed that I could get a couple more masks easily by cutting along the collar. Then I got a couple more from around the armpit area, and before you know it, I had 9 masks. A few look a bit goofy, but they all accomplish the purpose of stopping flecks of spittle from passing through in either direction. From what I have gathered so far, masks like this, plus lots of hand washing, will drastically reduce the transmission rate of Covid 19 virus, which is a goal we can all appreciate.
After I made the masks, I stuffed them all into a 2 gal. freezer bag, sprayed some alcohol into it, then closed the bag and placed it on a sunny window ledge. Alcohol, heat and UV’s should sterilize the masks pretty well.
Pro tip: After you take a mask out of the alcohol bag, let it dry out before putting it on. Damn, breathing in that alcohol burns the nose!