No that it answers your question, but the average concentration of oxygen in the atmosphere is roughly 21.5%.
Sorry, oxygen in atmosphere is 20.8%, whatever the apparatus produces is up to device.
My bad, I was way off base with that, and we all know the concentration is exactly the same, everywhere all the time. The point being that the 29% the op mentioned, is around 8% (feel free to calculate the exact percentage for the rel time local atmospheric oxygen concentration) higher than atmospheric, but a long way from 90% the Dr. has prescribed.
