Deep Stops Recreational Divers

[rsingler]

@rsingler I'm interested in the rational for your statement above. Is it specifically PDIS or a more general statement regarding the deep stop function available on most dive computers offered today?

My comment was a function of my interpretation of the deep stop fallacy as it applies in general. See the @boulderjohn comment above, and specifically, see his excellent article:
Evolving Thought on Deep Decompression Stops

Much remains to be learned before we get a better answer, hence the myriad opinions, but I think it is becoming clearer that deeper stops than necessary only add to ongassing in slow tissues, which may carry a consequence for DCS. That final phrase is what is disputed, but the evidence clearly points in that direction, IMHO.
PDIS for rec diving is a pretty minor phenomenon in this regard, but if the theory is correct for tec diving, I believe it should be applied to no-stop diving as well, to lessen tissue decompression stress.

 

[scubadada]

So... What would diving for the Queen be?

Monarchical?

 

[boulderjohn]

Let's face it--over the years, different people have started using key diving terms in different ways. That happens everywhere--language is constantly evolving. In Renaissance England, the word "nice" meant "silly." You can see it used that way in Romeo and Juliet, when Romeo tries to stop the battle between Tybalt and Mercutio by telling them their quarrel is "nice." I don't think anyone today would be offended if someone said they were nice, just because the word used to mean something else. For communication to be successful, you have to have the common sense to understand a word in the meaning it was intended to convey, not another meaning that results from your preferred definition of the key terms.

In this conversation, different people have different definitions of words like "recreational" and "technical." If you insist on applying your personally preferred definitions to sentences someone wrote when they obviously meant something else, then you are interfering with effective communication.

I believe that in most cases in this thread, people are using "recreational" to describe dives of such depths and times that the algorithm they are using does not require a decompression stop. I believe that in most cases in this thread, people are using "technical" to describe dives of such depths and times that at least one decompression stop is required. That is how I understand their posts, and there would be no point in quibbling over their use of those terms.

 

[rsingler]

"...a rose by any other name would smell as sweet..."

 

[Eric Sedletzky]

I'm looking.

I contacted NAUI headquarters and asked for the research behind their advocacy of deep stops. They pointed to a 2008 study that is a bit controversial. I contacted GUE headquarters more than a month ago to ask for the theoretical basis of Min Deco. I was referred to one of their people who was at the time too busy to respond, but I was promised an answer soon. I have sent a couple of reminder emails, but I have not gotten the response yet. In a ScubaBoard thread, a non-authoritative explanation said that it was a recreational dive application of a Bühlmann decompression program with deep stop GF settings. I am awaiting an official response.

That is an honest productive answer.
Thank you..

 

[shurite7]

For the purpose of this post it is for those who are not participating in any form of technical diving. Perhaps I should have given a definition of recreational diving so that people couldn't hijack the term. I was simply curious, knowing the limitations of a forum poll, to see how many people on SB conduct a deeper stop and if so at what depth, half the depth or half the pressure, in addition to a safety stop around 15'.

It has already been pointed out that NAUI (as well as GUE's and UTD's min deco as boulderjohn has pointed out) advocated deep stops for those diving within the recreational (meaning less than 130', no mandatory decompression stops, and no mixed gases other than nitrox of less than forty percent). This I already knew which prompted me to post the poll.

Technical diving, the use of mixed gases such as trimix or required decompression stops during ascent, is irrelevant to the original question.

 

[Bob DBF]

So... What would diving for the Queen be?

I was being a bit parochial, US dosen't have a monarch and I didn't think of anywhere else. No slight intended to the Queen, or her subjects.



Bob

 

[rjack321]

I was simply curious, knowing the limitations of a forum poll, to see how many people on SB conduct a deeper stop and if so at what depth, half the depth or half the pressure, in addition to a safety stop around 15'.

Help
What is "around 15ft"?

On a 100ft square profile for 30mins on 32% I would:
ascend at 30ft/min for 2 mins,
start slowing down around 40ft,
then do 1 min at 30, 2@ 20ft, 2@ 10ft

Total time to surface = 8-9mins.

I answered "no, I do not conduct deep stops" did I answer wrong?

 

[shurite7]

Help
What is "around 15ft"?

I've heard plenty of dive guides during my trips tell the group to conduct the safety stop between 20 and 15 feet. When I lived on the east end of Cayman, the windward side - meaning rough seas - the depth of the safety stop was written as 20-15 ft on the map that we drew out for the divers. when the seas were rough, normal during the winter months, then people were encouraged to stay between 15 and 20 feet. In any case, many recreational divers, in nice (today's def, not the old meaning) calm waters, tend to hover up and down around 15 feet when they don't have anything to hold onto.

"around 15ft" has nothing to do with a deep stop, half the max depth or half the max pressure.

 

[dewdropsonrosa]

Not so much "stops" as emphasizing a slow rate of ascent.
100 ft to safety stop depth should be taking 3 mins at least.
Too many recreational divers "rush" to 15 ft, do 3 mins and then "rush" to the surface.

I think Deco for Divers quotes a study that found most recreational divers ascend from their safety stop to the surface at 200 fpm. Perhaps we should be amazed that we don't see more obvious signs of decompression stress when this is the case?