Deep Stops

[BRW]

Speaking of deep stops -- check out the article in Alert Diver
about Haldane Deep Stops. It's patently FALSE-- Haldane
couldn't put deep stops into a consistent dissolved gas
only computational format, didn't introduce them ad hoc
into his published RN schedules, didn't test deep enough to
see their efficacy, didn't advocate them, and paid lip service
to them. The real world tech diving community is up in
arms about the article because it's a misrepresentation of fact,
and because of the author. Tech diving in the last 15 yrs
pioneered deep stop technology, developed the correct dual
phase models, and validated same with 1000s of human
dives. Not goats at shallow exposures on air.

Mike suggested that some of the Haldane versus Hill facts
in the article are also flawed -- I am going back to Leonard
Hill's paper to check on this too. More ca ca for sure.

Coming from DAN, this is not too cool. DAN seems to be wanting
to jump aboard the deep stop band wagon, but doesn't have
all the facts yet,

Bruce Wienke

Program Manager Computational Physics
Counterterror And Countermeasure Dive Team Ldr


:boom:

 

[Dr Deco]

Dear Readers:

In the trenches - - -

You are getting a chance to view science as it is played out at the working level. I am referring here to the controversies between deep and shallow stops and single phase (all nitrogen dissolved) versus dual phase (some nitrogen in bubbles). This is a question that is being played out in real time, and the non-scientist portion of the world rarely is afforded the opportunity views this process.

Science is a “body contact sport” and as such it will often involve considerable pushing around by the players. This is particularly evident in such areas as evolutionary theory (as promulgated by the later Stephen Jay Gould) or the controversies involving the origin of the physical universe (what is commonly described as “The Big Bang). We are seeing something on a smaller scale here concerning deep stops.

Regrettably, most of the diving community on the professional level has been trained to think in the classical, canonical methods of the Haldane approach. Recreational divers, not jaded by academic training in dive physiology (such as encountered by university professors), do not have difficulty with concepts that two phases (i.e., micronuclei) are present. Academic scientists in contradistinction are flummoxed by this at the working level. There is no question, in my experience, that they know the word “micronuclei” , but they do not understand the concepts.

E. N. Harvey referred to the generation of micronuclei by hydrodynamic cavitation in the 1940s. Nuclei did not supplant the time-invariant (= never changing) stable supersaturation ideas of Haldane then - - and it still has not. Inroads on the acceptance of this concept are being made.

When something is found, we often see everyone claiming that they were a part of the discovery. Often these were originally the most vociferous opponents of the concept. Some of the DAN scientists are of this ilk.

I am curious to see what happens in the years to come.

Dr Deco :doctor: