Great question. Intuitively, the time in chamber for each treatment might be based on the ATA available. So if it is, say, 1 hour 50 minutes with 2 ATA, one might want treatment to last 2 or more hours at 1.3 to 1.5 ATA. Personally, if there was a 1.3 ATA treatment available locally I would go for it.
I just finished 35 of 40 2ATA HBOT sessions that I had to travel 450 miles round trip for. Fortunately I was able to stay with my son who lives a 20 minute walk from the facility.
I plan on doing the remaining 5 sessions next month but at a facility 200 miles roundtrip from me. What I wonder about is if there is any drop off in effectiveness when the treatments are discontiguous. My 35 treatments were over a 13 1/2 week period because I suffered a pneumothorax after a bad fall and had to postpone treatment for a month while it healed. My remaining 5 will be after a 7 week hiatus.
I had two reasons to seek hyperbaric therapy. First was to counter the effects of IMRT on my prostate and pelvic lymph nodes and hopefully overcome radiation proctitis symptons. The second reason was to counter some negative effects on my right leg after a total knee replacement wounding. A side benefit was to experience the rejuvenating effects (anti-aging?) of the treatment.
Time will tell more but at this point in time I have not had a resolution of my radiation proctitis symptoms, my right leg has more "life" in it now but with room for more improvement and the anti-aging effects will be subtly expressed as I continue to age using future blood tests as a barometer.
I just received my first "electro-acupuncture" treatment for "overactive bladder" so I am hopeful that I will see improvement over the next several treatments. Fortunately, that clinic is only 70 miles round trip!
Best wishes to you.