Google Scholar: isobaric counterdiffusion scubaHmmm. Do you have links to pertinent peer-reviewed articles written by a physiologist (rather than to blogs written by a theoretical physicist)?
rx7diver
Enjoy
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Google Scholar: isobaric counterdiffusion scubaHmmm. Do you have links to pertinent peer-reviewed articles written by a physiologist (rather than to blogs written by a theoretical physicist)?
rx7diver
@lowwall,
That only works because you use imperial units. You can't expect the rest of the world to hold a stop that ends in .5.As for me, I set my last stop to 10 feet, but I don't go there. As soon as I am finished with the 20 foot stop, I go up to maybe 15 feet or so. That way I can do mild exercises to increase perfusion and relax without having to be too anal about my depth.
That only works because you use imperial units. You can't expect the rest of the world to hold a stop that ends in .5.
Regardless of the fraction I think this principle is rather practical and I do the same. Clear the 6m o2 stop but only ascend to 5m (16.404 ft)As this thread's resident nit picker I feel obligated to point out that it actually ends in .4559274326701081, give or take a few decimal digits and assuming the water is salty.
Could also watch the "ceiling" on the computer and move up earlier once ceiling is less than 5m but I've never bothered and just wait the extra few minutes for the 3m stop to be available. I'm not sure if the computer would consider that a missed stop despite not violating the algorithm (though that's not really a big deal on a shearwater but could still be annoying)Regardless of the fraction I think this principle is rather practical and I do the same. Clear the 6m o2 stop but only ascend to 5m (16.404 ft)
Could also watch the "ceiling" on the computer and move up earlier once ceiling is less than 5m but I've never bothered and just wait the extra few minutes for the 3m stop to be available. I'm not sure if the computer would consider that a missed stop despite not violating the algorithm (though that's not really a big deal on a shearwater but could still be annoying)
very true and it will also slightly accelerate your deco due to the average supersaturation being higher since with the staged stops you only briefly touch the supersaturation limit when you first arrive at a stop. However riding the ceiling would also mean that you're using the model in a more aggressive way than which most of the testing of the model was likely done. Having said that, most implementations add a lot of extra conservatism than the original model anyway. I don't hear of anyone using GF100/100Buhlmann wrote in Decompression Sickness that the only reason for spacing deco stops at .3 atm that he could find is that "we've always done it that way" and that in practice smaller increments would likely be hard to maintain in open water. In a controlled environment like a chamber, Herr Doktor said one could "ride the ceiling" continuously and do away with discrete stops altogether.
The ascent method was not random. I am a little fuzzy on the details, but I know a century ago the debate was going on. Was it better to do a series of stops during ascent (as Haldane advocated) or do a slow continuous ascent (as Hill wanted)? The series of stops won the debate. Haldane's experiments with goats indicated that a series of stops was superior to a slow continuous ascent.It is a fascinating thought that we are still doing it that way because we always did it that way. I wonder if there have been any studies to compare the two approaches. I'm not even sure how you would fairly compare them.