So many people go in there hyperbaric chambers and don't know how to pace their session. Some people go in for 2 hours and others go in an hour in the morning and an hour at night. There are advantage and disadvantages of both ways and depends on the reason using the chamber. Someone with autism and someone with a TBI I would recommend different ways to pace the session.
Many parents put their autistic children in the chamber because they want to oxygenate their brain and think the more the better. I strongly advise parents not to put their kids in at these "deeper levels". There is no really quick super fast improvement. It is better based on all the people I talked to that starting at the lowest level 1.3 ATA and then slowly gradually build their way up to higher pressures (in legal places only). Not all people can handle 1.5 ATA. Some people have
HDOT (High Dosage Oxygen Therapy) is another popular usage. HDOT based on what I have learned can only be done at 1.5 ATA or higher (legal places only). It is done with pure oxygen tanks, not the oxygen concentrators that most people use. If less than 1.5 then the body can over oxygenate and the oxygen is not burning but "oxidizing" and that is what to avoid at all expense. I will say it can be very dangerous to use 100% oxygen in a soft shell chamber.
Note: I advise people NOT to use 100% pure oxygen even at low levels with any soft shell hyperbaric chamber.