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Of course, deeper stop style planning and bubble models have been the most successful deco approach in rec and tech dives for the last 15 years.
VPM follows the basic gas kinetic theories and formula (as used in every dive computer), which eliminates the possibility of the above.
This is nonsense Ross. It implies that the "success" of deep stops and other approaches have been measured and compared, and that deep stops are better. In fact, the opposite is true. Every human study of the use of deep stops in decompression diving that has emerged so far has found that deep stop approaches are less successful. There are two studies of the effect of inserting a single deep stop in the ascent from no decompression dives on post dive bubble counts, and they draw opposite conclusions. This is hardly a basis for claiming that "deeper stop style planning and bubble models have been the most successful deco approach for the last 15 years". They have been a "popular" approach prior to emergence of the relevant data, but that is very different to "successful".
This is completely incorrect. The gas kinetic formulae common to all decompression planning give us the ability to track hypothetical tissue gas pressures during decompression, but different models have completely different approaches to what they do with that information (how much supersaturation you allow in what tissues and when). That is why they prescribe different decompression Ross.
I can't believe you keep saying this. Do you really believe it? I suppose it is possible that you do. Your recent claim that it is the tissue half time and not tissue blood flow that largely determines gas uptake and elimination provided a clear demonstration of how little you really understand about "basic gas kinetic theories".
Simon M
The most dominate deco method in the last 15 years, has been the deeper stop / slow ascent method across all types of diving.
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The most dominate deco method in the last 15 years, has been the deeper stop / slow ascent method across all types of diving. At the same time the injury rates / numbers / treatment / percentages / what-evers, have gone down, as recorded by every reliable metric, measure, and statistical tracking body.
You lost that argument because were not able to prove your claims.... or provide anything to counter my claims about the way models address this issue.
So now you make up straw man arguments, and invent false attributions about my posted comments... as yet another cover up.
Exciting model gas kinetics theory and formula, follow the concept that the individual tissue is the limiting component of the uptake / off gas rate, as represented by a tissue half time value set. Its the balance of partial pressures against the tissues density and its ability to absorb excess inert gas, represented by a half time value. That is the basic theory you will find in all current models in use (VPM-B, ZHL, VVAL and more). The parallel tissue models do not support a perfusion limit in their calculations. Same can be said for the various serial tissue model designs
Our experience shows that on/off gassing rates / quantities, seemingly are not controlled by perfusion limited. Instead we appear to be limited by tissue absorption rates, exactly as the models are designed and operate.
I think the detrimental effect of deep stops on the slow compartments depends on the gas you breathe at the stop,...
All compartments? None of them will still be ongassing?If the gas breathed on a given stop permits off-gassing across all tissue compartments, then i really see no drawbacks to initiating staged decompression from as deep as possible.