TomD
I don't feel that daring going to the hardware store, but then I have a 3M Racal air supplied helmet. It is amazing that in the most developed country on earth people are still wandering around wearing cloth masks. A DIY Racal plan is on Thingieverse. Even kids who play paintball have ponied up for carbon fiber air tanks. The helmets are super easy to McGyver. In fact the lab ones are mostly tyvek and disposable, so not particularly complex. It is amazing what the people who take all this stuff seriously consider serious.

I take PPE very seriously, but there is no good evidence masks work, and the premise is based on projectile transmission, while the evidence points to aerosol transmission. Racal is perfect for protecting me from that.