FanOfOurForebears, welcome to The Cardboard!
For those who truly have breathing problems, mask wearing is not required, and is not recommended. All the requirements for masks that I've seen have exceptions for this and other situations. (CA, SMC, KS)
To minimize chance that someone misunderstands the situation, you might want to get a note from your doctor indicating that you have a medical condition that prevents you from wearing a mask, as well as a copy of whatever order requires wearing a mask that also has the exemptions for those with breathing issues. Some business might not want to let you in at first; such documents should clarify that you are not required and are not recommended to wear a mask. (To clarify: In the orders I've seen, you are not required to carry such documentation. I just think it might make things easier if someone isn't aware of the exceptions. If it was me, I might get a button: "SORRY, I can't wear a mask. Thank you for wearing yours.")
There are different reasons for low PO2. I rarely see mine get up to 96, mostly 92-94, but mask wearing isn't an issue for me as long as I stay out of oxygen debt. But then, I don't have COPD.
For those who truly have breathing problems, mask wearing is not required, and is not recommended. All the requirements for masks that I've seen have exceptions for this and other situations. (CA, SMC, KS)
To minimize chance that someone misunderstands the situation, you might want to get a note from your doctor indicating that you have a medical condition that prevents you from wearing a mask, as well as a copy of whatever order requires wearing a mask that also has the exemptions for those with breathing issues. Some business might not want to let you in at first; such documents should clarify that you are not required and are not recommended to wear a mask. (To clarify: In the orders I've seen, you are not required to carry such documentation. I just think it might make things easier if someone isn't aware of the exceptions. If it was me, I might get a button: "SORRY, I can't wear a mask. Thank you for wearing yours.")
There are different reasons for low PO2. I rarely see mine get up to 96, mostly 92-94, but mask wearing isn't an issue for me as long as I stay out of oxygen debt. But then, I don't have COPD.