What is oxygen level guideline, before needing supplemental oxygen if you are out of shpe?

BASED ON PO2/O2 SATU. Grp1 po2at or below 55mmhg(awake&at rest) if higher but fall to these levels during sleep or>10mmhg, or5%o2 sat+ corpulmnale, covered for exercise only if the levels drop to groupa level during exercise. Grp2 po2 56-59 mm hg or o2sat89%, and documentation of edema/chf, or cor pulmonale by pul artery pressure, or erythrocytemia withhct>56%.