Two stories.
First, soon after all this mask stuff started, I was digging a garden box. I was chopping up a sand base that had been used for artificial grass. Lots of dust, so I put on an N95 mask. After working for a short time, I started breathing a little heavier, but I couldn't get enough oxygen. Stupidly I kept at it, and then finally gave up. Afterward, I felt like I had sprained my lungs. The extreme pulling I had to do to get enough oxygen to keep working had left an effect long after I stopped the work and took off the mask.
Second, my mother-in-law had to go to the doctor for a non-CV follow-up visit, and ended up sitting in the waiting room for over an hour. She complained about having difficulty breathing, but remained CV-compliant. When she told the doctor, the doctor said that the masks had an effect on her, too. Normally her blood oxygen measurement was 100%, but when she was wearing a mask, it only measured 92% -- a significant difference.
Masks suck. My son is planning to fly soon to visit his girlfriend in London. He's planning to wear a painter's mask on the plane, but he's worried that he won't be able to sleep in it. I'm worried that he won't be able to get enough oxygen, especially when he's sleeping and especially in the rarified airplane air (they only pressurize to simulate 7,000 ft). On long flights, people get blood clots and stuff even without a mask.
This reminds me of my appendectomy. In November of 2001 I flew form Arizona to a conference in Washington, DC. So soon after 9/11 everyone was still completely paranoid so we were not allowed to move for the entire 5-hour flight. A week later I had to have my appendix removed. Coincidence?
Those little Oxymeters that clip onto your finger are cheap,
and available at most any pharmacy.
Get one, folks, and show people what they have been
frightened into doing to themselves and their loved ones!
Starting with "Hypercapnia".
(Especially if you already live at any altitude!)
Most everyone will show a few % blood/oxygen sat. loss
at least, after even just a few minutes being masked.
(with most masks.)
~Easy