An experiment and results on CO2 build up in N95 masks [pdf](kylebenzle.com) |
An experiment and results on CO2 build up in N95 masks [pdf](kylebenzle.com) |
The space within a respirator is known as "dead space" and should be minimized. There were a lot of novel ideas for respirators in 2020 that had to learn this the hard way, including some full-face snorkeling masks. Full-face respirators separate out the nose and mouth section for this reason.
Your pictures do not show a 3M 8210 N95 as you claim. They show an earloop KN95 of unknown manufacturer, which makes me doubt how scientifically this test was performed.
1. That's what I thought too, so went to a lot of work to test levels before, during and after breaths. I included results for at the end and beginning of a breath and found that levels JUST BARELY got below the OSHA allowed limit at the end of breathing in.
2. Yes, there is a lot of dead space on normal masks, the that's where the CO2 build up comes from.
3. I have found similar studies, one weirdly also vacuums the air out at the same time, but I'd suggest looking into it if interested and believe what you want. I'm just glad I know finally for myself, thought others might like to know too, and am satisfied :)