| Law and PpO2 (not FiO2)
The mix you breath at each depth must have more than 0.160 ATA O2 in it. That can be a 17% near surface, or a 4% mix below 31 meters.
Another article limits the max O2 you breathe, here to 1.60 ATA max.
So playing open circuit you may dive very deep but must change your mix while descending or ascending. In fact this a common practice in Trimix dives worldwide, and is the basis of CCR diving.
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See you soon under surface Jacques |