Most people stay in way longer than they need to. Unless there is a medical reason or broken blood vessels, or other tissue injuries, staying in the hyperbaric chamber once the body is oxygenated to capacity and staying any time longer than this is something that I do not recommend (learn about burning oxygen).
Avoiding longer session:
So many people go in their hyperbaric chambers and think that longer time is better for the. Even those that have 1.5 ATA chambers who get oxygen saturation in about half the time still go in for longer than needed.
After about an 1.5 hour to 2 hour is all that it takes to bring the blood levels to 100% oxygenation. Any 20 dollar oximeter can tell you this.
If someone goes in for 4 hours and they get 4 hours after the session that their cells have this extra oxygen. That is 8 hours of extra oxygen. If someone goes in their hyperbaric chamber for 2 hours in the morning and 2 hours at night, that's still 4 hours in the chamber and 8 hours of residual oxygen. Thats a total of 12 hours. The first way only gives 8 hours of oxygen. So, longer is not always better but paced out sessions is what many people try to do when trying to maximize their oxygen potential for the day, unless they have all day to be in the hyperbaric chamber or want to sleep in there.
Also, once the body is fully oxygenated and the pressure is over 1.3 ATA and that pressure since it is so high it keeps pushing more compressed oxygen in the cells, that can give us the bends when the blood is over oxygenated. This is why there are laws passed in many places that they don't legalize chambers over 1.3 ATA.
For those getting 1.5 ATA chambers, keeping a constant check on the oximeter will tell when the exact time to get out as it is important because these are not at all the same as the 1.3 ATA chambers. With the 1.3 ATA chambers it is much harder and I mean MUCH harder to get the bends with a longer session. This page is mainly for those getting a 1.5 ATA chamber in places where it is legal.
Note: those who get 1.3 ATA chambers who try to change out their release valves to 1.5 ATA release valves, it can probably work for a while but sooner than later people call me and say their zippers have failed and their is a leak in their chamber. This will void any warranty on a 1.3 ATA chamber. 1.5 ATA chambers are made to go to higher pressure. Also, the compressors that come with 1.3 ATA chambers usually can't go to 1.5 ATA.
I can answer any hyperbaric chamber related questions on my Hyperbaric Quiz. Take my quiz here.