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Surely he did not drown and stay dead for 2 days, saturating his tissues, then received resuscitation and decompression.
There has to be more to this story I am missing...
Was he living off of an air space?![]()
Back of the envelope:Either this guy has a great SAC or he was in a pretty big airspace.
Wouldn't he need about 100000 liters of air to last 48h at 30m while resting before CO2 buildup would become unacceptable?
Back of the envelope:
The average adult while resting will use about 6.5 liters per minute of air. ( source: Respiratory minute volume - Wikipedia, the free encyclopedia )
There are ( 60 X 24 X 2 = ) 2880 minutes in 2 days.
So on open circuit someone should be able to get by with around 19,000 liters.
Since this would be closed circuit, the volume needed would be significantly less.
I don’t know how, or whether, the increased partial pressure of oxygen would affect this.
At least one of us has an error in our calculations.
Ah, you were talking pre-compressed volume. I was talking compressed volume, and assumed you were too, because thats what he was breathing and the volume of the air pocket hed need.For starters you forgot that this is taking place at 30m so multiply your calculation by 4...
So, go with 12 lpm. 40,000 liters would allow him to do it open circuit. Thats a pretty big space, about 2m X 4m X 5m, but still conceivable in a ships compartment. But thats an upper limit. Still need to factor in the key item which we already were aware of, (and beano also pointed out): CO2 buildup.While 6.5LPM may be reasonable for someone warm and calm, I don't believe that is a realistic SAC for someone stressed out and in an environment where he's probably losing body heat quickly and probably shivering. So try replacing 6.5 with at least 12LPM
I assume fallout shelters are intended to keep the occupants pretty healthy. This sailor could well accept sick.Finally this is not OC, the problem is CO2 buildup in a closed space. I ran my calculation off guidelines for sealed fallout shelters, I don't remember which site gave the figures.
Adaptation to increased levels of CO2 occurs in humans. Continuous inhalation of CO2 can be tolerated at three percent inspired concentrations for at least one month and four percent inspired concentrations for over a week.