Is UTD still a "fringe" organization?

[Kyle Knick]

I love the great dive pod cast. I have picked up so much information from James and Brando, they have made me think about so many different aspects I never would have known. I still don't know all I don't know

 

[Wibble]

I love the great dive pod cast. I have picked up so much information from James and Brando, they have made me think about so many different aspects I never would have known. I still don't know all I don't know

That’s a great step forward! The great thing with experience is knowing that there’s so much you don’t know — almost could say that the more one dives the less one knows!

Starting with Advanced Open Water isn’t.

 

[happy-diver]

As I explained the cult of those that quote not knowing what they don't know, to my 90yr old father
he proceeded to call me an idiot
and wouldn't talk to me anymore

 

[Wibble]

As I explained the cult of those that quote not knowing what they don't know, to my 90yr old father
he proceeded to call me an idiot
and wouldn't talk to me anymore

Fathers are like that. Some get more bloody minded with age.

 

[happy-diver]

I'm not too close, but not too far behind either, wish it were further but then it wouldn't be me
and agree with the old man wholeheartedly

I love the inanity of Gareths all pilots are stupid forum, the parotting followers that use their adopting
of special terms, coined phrases and belonging to a group self labeled as stupid as a badge of courage.

Like some groups in society congratulate themselves for staying out of jail, got a like from him yesterday

I've got the book bought the course although I haven't done it, just like to know who I'm diving with

 

[eelnoraa]

... He sold his UTD share to his partners and is no longer affiliated with UTD....

Wow, I have this suspect for a while. Now you confirm it. Hmm. I wonder what happened. I met AG a few times, although never trained with UTD, I think he is a cool guy. Local UTD divers are also very solid.

 

[andrespp]

Goodness, did you even read my whole post? As I explained, prior to Doppler this term at the scientific level would imply the existence of bubbles and is used as such in early documents. If you were not bent then you cant have bubbles. It is not me, this is what was believed. Doppler research showed that to be wrong and if that meaning is carried today then we are all bent whether we have symptoms or not. Modern discussion is better served by silent bubbles and symptomatic bubbles.

From the very beginning of deco theories (Haldane) the assumption was that after every dive, bubbles are present in the body. The question was about what amount of bubbles can be tolerated before having noticeable DCS symptoms.

 

[rjack321]

Wow, I have this suspect for a while. Now you confirm it. Hmm. I wonder what happened. I met AG a few times, although never trained with UTD, I think he is a cool guy. Local UTD divers are also very solid.

Andrew has always been a starter not a finisher.
he was in pretty much on the groundfloor of GUE
initial investor in DiveXtras
initial investor in red sea explorers
started UTD

he's moved on from all those ventures. Selling his share of UTD isn't out of character

 

[CAPTAIN SINBAD]

From the very beginning of deco theories (Haldane) the assumption was that after every dive, bubbles are present in the body. The question was about what amount of bubbles can be tolerated before having noticeable DCS symptoms.

I am sorry but this is purely incorrect. I present the following quote:

"Through experimentation, Haldane developed the theory that liquids such as blood can withstand certain level of super-saturation without forming bubbles. He called this maximum level of super-saturation the "critical limit." (TDI Decompression Procedures Manual page 67)

So the man actually believed that if you are below "critical limit" you are "without bubbles." This is why his model is called dissolved gas model because it assumes that nitrogen will be stored in the muscles without bubbles in a state of dissolved gas up to a certain pressure differential. TDI manual further goes on to say how Doppler testing disproved this assumption.

"Doppler testing has proven the existence of silent bubbles, even on dives that obeyed Haldane's critical limits." (TDI Decompression Procedures Manual page 68)

 

[lowwall]

I am sorry but this is purely incorrect. I present the following quote:

"Through experimentation, Haldane developed the theory that liquids such as blood can withstand certain level of super-saturation without forming bubbles. He called this maximum level of super-saturation the "critical limit." (TDI Decompression Procedures Manual page 67)

So the man actually believed that if you are below "critical limit" you are "without bubbles." This is why his model is called dissolved gas model because it assumes that nitrogen will be stored in the muscles without bubbles in a state of dissolved gas up to a certain pressure differential. TDI manual further goes on to say how Doppler testing disproved this assumption.

"Doppler testing has proven the existence of silent bubbles, even on dives that obeyed Haldane's critical limits." (TDI Decompression Procedures Manual page 68)

The TDI manual appears to be mischaracterizing Haldane's work. Nowhere does he (and his fellow authors) state that the 50% reduction in pressure that they found to be safe is due to a complete avoidance of bubbles. Instead the number was based on a review of previous diving and tunneling incidents. No severe symptoms had been recorded from a pressure less than 2.25 atmospheres absolute (1.25 above sea level or 41 fsw). He simply rounded that down to 2.0 to give a safety margin and, no doubt, to simplify calculations. He then performed experiments to check the validity of this assumption.

I've attached the actual paper. It's fascinating, if somewhat gruesome if you read the experimental section. The authors introduce all the bases of modern decompression theory, including tissue compartments, staged decompression and saturation curves. It's also surprisingly readable. Perhaps because it was meant to be a practical rather than a purely theoretical work.