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Hi Daniel I can see how you might get the no-stop result if you assume 100% inert gas (as did Haldane), but I do not know if a no-stop dive will always give the lowest ISS (assuming 100% inert gas). In fact, typically (but not always) the optimized value for Pthr is equivalent to the value...

Hi Daniel, it has been a while since we chatted, or that I logged into SB. There is lot to answer in your posts. I am away diving, and I am waiting for my buddy to wake up so we can get out, so this might be overly brief and not completely thought through. You suggestion that PDCS=f(ISS) and...

So you are accusing me of scientific fraud Ross. The appropriate forum for that is to take it up with my institution.

I do not want to hi-jack this thread further away from the very clear and accurate post on the limitations of the NEDU deep stops trial (thank you Gozo Diver), and certainly do not want to re-hash all that was discussed in the several other threads, including a 1000+ post thread on this forum...

As has been noted previously in this thread, in response to the initial question, increasing respiratory minute volume without a change in the work the diver is doing (i.e. hyperventilating) would not be expected to have much effect on inert gas exchange or on the risk of decompression sickness...

Ryan There are a couple points to consider. First, the anatomy is not identical and perhaps does not lend itself to development of sufficient supersaturation Second, it may be that bubbles do form, and there is a single report of knee pain after a nitrox-to-heliox (the opposite of what we are...

Just to follow up a bit more. The natural question is, “if helium is taken up faster than nitrogen into the inner ear fluid space faster, why doesn’t this impose a helium penalty, whereby the inner ear imposes a deeper first stop if diving heliox than trimix or nitrox?” This is a complicated...

Not really. The helium penalty information relates to the observation that helium and nitrogen half-times are probably similar in relatively fast exchanging tissues that control the early stops during decompression from most bounce dives. Although most gas exchange is primarily limited by the...

Hi Simon, There is actually a third study, as Beester described. I do not know much about it, but have also spoken to participants. David

Some similarities between the initial evaluations of the whole schedule in VPM-B that you describe and probabilistic algorithms. The key difference that explains the behavior noted by JohnnyC, is that in VPM-B, based on the evaluation you describe, an ‘allowed supersaturation rule’ is set at the...

Probabilistic decompression models have some fundamental differences to deterministic decompression algorithms (e.g. ZH-L16 or VPM-B) that result in quite different looking schedules. Probabilistic schedules will not always produce monotonically increasing stop times and will even skip stops...

No there is not. I put out the pointer to the descriptions of the models because Leadduck was implementing a similar model from the 1997 paper, and LEM is more relevant for technical divers, and there are published schedules with which to compare. David

If you are interested in probabilistic decompression models there is a much bigger literature in NMRI and NEDU technical reports available on Rubicon. LE1 is quite dated now, and in particular it does not deal well with high oxygen fraction. A more relevant model would the LEM...

I believe in these last few posts you are mixing up two possible ways in which VGE might be used. In an earlier posts you mentioned predictive power and specificity.These are measures of the utility of a binary classification test, for instance a diagnosis of DCS in an individual based on VGE...

Returning briefly to the topic of the thread, those are the old 1957 no-stop limits, we retained those in USN Diving Manual, Rev 6, but they will be replaced in Rev 7. The reason they are all 5 minutes, is because back when the 1957 tables were constructed, computing power was limited. The...

The biological variability in gas uptake, washout, and VGE formation is a question, but not one relevant to the issue at hand: your refusal to accept the demonstrable correlation between VGE grade and risk of DCS, symptom severity, and extravascular free gas. Since you mention pulmonary DCS...

But I want to get back to Leadduck's interesting post, Ross. Which part do you think is "made up", the standard practice of jumping schedules (decompressing on a schedule for a longer bottom time) to reduce risk when working hard on the bottom or diving in cold water, or the VPM-B schedule for a...

Your misrepresentation of this paper and of the scientific consensus about VGE are covered in the other thread, post #1217 is a good place to start Deep Stops Increases DCS

This is just wrong, Ross. Rather than engage in the surreal exercise of arguing with you about the meaning of a statement I wrote, let me set you some home work based on documents I know you have. The statement in Mollerløkken A, Blogg SL, Doolette DJ, Nishi RY, Pollock NW. Consensus guidelines...

Yes, those last were the conditions of NEDU TR 11-06. I must need some additional punctuation in my earlier post. David