Deep Stops Increases DCS

[Rich Keller]

I just wonder... if, as someone mentioned here earlier, the goal was to demonstrate a general principle, rather than evaluate specific profiles/models actually used in practice, why not resume experiments on goats? One could have performed many more experiments, and on a wider range of parameters this way...

They were testing what the actual limits are and in order to do that they had to take this to the extreme on air. This is done to provide a baseline from which the algorithms for other models are derived. The people who think their model is better even though it was derived from an old baseline that this study has proved to be wrong are placing themselves at risk. The experiments on sheep were only done because their circulators system reacts the same as ours so the short and long term effects of DCS on the body could be studied without placing divers at risk.

 

[ajduplessis]

All this study show is that the use of extremely long uncalled for deep stops will result in more DCS incidents when compared to a lot shorter and shallower stops. Extremely scientific stuff.

 

[tomfcrist]

Be careful AJ, the WKPP boys will jump in to tell you that you are stupid and can't read

 

[PfcAJ]

All this study show is that the use of extremely long uncalled for deep stops will result in more DCS incidents when compared to a lot shorter and shallower stops. Extremely scientific stuff.

You're stupid and can't read.

Did I do that right?

 

[tomfcrist]

Pretty close AJ. Would have been more predictable if you also called him a stroke, told him that there is nobody smarter than you and that you are the end all be all of deco theory. You could have topped it all off with saying that if people don't agree with you then they are morons.

 

[ajduplessis]

Typical response when the clever guy(s) have no response, I expected nothing else.

 

[PfcAJ]

Pretty close AJ. Would have been more predictable if you also called him a stroke, told him that there is nobody smarter than you and that you are the end all be all of deco theory. You could have topped it all off with saying that if people don't agree with you then they are morons.

I'll try harder next time.

 

[tomfcrist]

Lmao.... You do that.

 

[ajduplessis]

All this study show is that the use of extremely long uncalled for deep stops will result in more DCS incidents when compared to a lot shorter and shallower stops. Extremely scientific stuff.

You're stupid and can't read.

Did I do that right?

 

[UWSojourner]

I just want to summarize some of the information that resulted from the debate last year over on RBW.

During that debate the NEDU profiles (A2-deeper stop, A1 shallower stop) were compared to profiles that were generated by VPM-B and GF. The comparisons were done in a number of different ways in order to see how similar VPM-B and GF might be to the tested NEDU profiles.

As more and more information was digested and compared, my conclusion was that the VPM-B profile would likely behave quite a bit like the A2 profile (i.e. higher DCS) and a GF profile more like the A1 profile. So I do think the study has a lot to say to recreational divers who plan decompression dives. Obviously everyone has to decide for themselves, but here are some links that might help you think through the issues.

Profile similarity
Compares shapes of the A2 and VPM profiles

Heat map similarity
Visually compares patterns of supersaturation in the A2,VPM, A1 and GF profiles

Deep stop skew similarity
Compares and index of how much a profile "skews" toward deeper stops

Risk function similarity
Compares a profile risk function for each of A2,A1, VPM and GF.

In addition, Dr. Doolette has a presentation here that I think is very good.

Happy New Year!