DIR- GUE Why are non-GUE divers so interested in what GUE does?

[crofrog]

I've probably been in half that in the Puget Sound (Tacoma Narrows, Deception Pass).

Having been in and around deception pass a lot (family lives on the island) it can hit 9kt pretty regularly. The Gulf Stream never gets close to that.

 

[RedSix]

You say that the algorithms are only greatly simplified models. Yet, ratio deco is even simpler than those algorithms that employ logarithmic equations on data to several decimal places. In the 2006 printing (the copyright is 2000) of "Doing it right: The fundamentals of better diving" on page 119 they list a baker's dozen problems with computer diving. Some of the reasons are due to the poor quality and limited features of computers at that time. For example: "Dive computers do not allow for diving helium in any format but the bulkiest and most questionable." Other reasons they give is that a dive computer is a crutch to enable divers to not learn and understand decompression theory. Still, another reason given is if the computer fails the diver will be left without essential diving information. All of the reasons they give have been overcome by modern up-to-date computers and backup procedures. Computers don't make you forget your training and education on decompression theory any more than driving a car makes you forget how to walk. It is simply another tool to bring along on a dive to help keep you safe. Finally, I would say the side effect of ratio deco is that you learn an inefficient method of decompression.

Believe it or not, VPM, Bühlmann etc. are all models. To some extend they describe what happens during decompression quite well. So well that most (> 99%) of the decompression dives are "safe". Nonetheless they are models. Models have errors. At some points even the models are not longer applicable. Like @crofrog stated above, there is no need to calculate decompression to the xth decimal place. On good days you might get away with cutting off the 6m-stop, on a bad day even half an hour more might get you bent. A human body cannot be described with 16 equations. It cannot be described with 100 equations. Bühlmann is a very good working model, but it is still a model and has it's boundaries.
Regarding GUE and computers, it has been said quite often before in this thread: GUE has changed since a few years. GUE does not say, that you are not allowed to bring a computer. GUE encourages you to be able somehow comprehend what is happening and hence be able so verify and understand what the computer is doing. And ratio deco helps you with this.
Based on the stuff you learn in T1 you can safely do some nice wreck dives in the range of 45 to 51m without using a computer. And you can easily adopted to changed parameters (a few meters shallower, a few meters deeper, bottom time longer or shorter) during the dive. You can do this without a computer, but nobody forces you to not use the computer.
(DIR-)World changes when proceeding to the T2 / CCR2 path. Here different "flavors" of ratio deco are thought. Dives get more complex, you also need to find your "style" of deco, which fits you / your body. Decide, deep stopp or not, what deco gases etc.
To plan the dives you can use GUE deco planner (which is used for decades now) or any software used on a computer.
Funny note: if you compare the deco plans of different softwares you will get even with the same sets of GF by a few minutes different deco plans. And really funny thing: it doesn't matter in the end. How long has been researched regarding usefulness of deep stops? Decades. Do we have a clearly answer now? Not really. There are some evidences which show that deep stops are not useful, but is there a proof? It is statistics, and you really need to be careful with statistics.

 

[Celt]

Believe it or not, VPM, Bühlmann etc. are all models. To some extend they describe what happens during decompression quite well. So well that most (> 99%) of the decompression dives are "safe". Nonetheless they are models. Models have errors. At some points even the models are not longer applicable. Like @crofrog stated above, there is no need to calculate decompression to the xth decimal place. On good days you might get away with cutting off the 6m-stop, on a bad day even half an hour more might get you bent. A human body cannot be described with 16 equations. It cannot be described with 100 equations. Bühlmann is a very good working model, but it is still a model and has it's boundaries.
Regarding GUE and computers, it has been said quite often before in this thread: GUE has changed since a few years. GUE does not say, that you are not allowed to bring a computer. GUE encourages you to be able somehow comprehend what is happening and hence be able so verify and understand what the computer is doing. And ratio deco helps you with this.
Based on the stuff you learn in T1 you can safely do some nice wreck dives in the range of 45 to 51m without using a computer. And you can easily adopted to changed parameters (a few meters shallower, a few meters deeper, bottom time longer or shorter) during the dive. You can do this without a computer, but nobody forces you to not use the computer.
(DIR-)World changes when proceeding to the T2 / CCR2 path. Here different "flavors" of ratio deco are thought. Dives get more complex, you also need to find your "style" of deco, which fits you / your body. Decide, deep stopp or not, what deco gases etc.
To plan the dives you can use GUE deco planner (which is used for decades now) or any software used on a computer.
Funny note: if you compare the deco plans of different softwares you will get even with the same sets of GF by a few minutes different deco plans. And really funny thing: it doesn't matter in the end. How long has been researched regarding usefulness of deep stops? Decades. Do we have a clearly answer now? Not really. There are some evidences which show that deep stops are not useful, but is there a proof? It is statistics, and you really need to be careful with statistics.

Great post, decompression stress varies dive to dive, and if a diver learns to recognise how it affects them personally they can take measures to avoid getting bent on long deep stressful dives. Working deep in cold dark water is not the same as a casual dive in clear warm water to the same depth for the same time. You should listen to what you're body is saying, and shorten the bottom time or increase the deco.

 

[ginti]

All of the reasons they give have been overcome by modern up-to-date computers and backup procedures. Computers don't make you forget your training and education on decompression theory any more than driving a car makes you forget how to walk. It is simply another tool to bring along on a dive to help keep you safe.

I agree on this point. Which is exactly why we use computers (despite we don't strictly need them).

Guys, just a point that maybe isn't clear to everyone: during the tec1, a computer isn't required. But they teach the principles of computers and how to use them.

 

[kensuf]

No I’m using miles because that’s what he originally shared he went 10 miles down in 30 minutes, and because as Americans we have to constantly use different units

I said 5. DIR- GUE - Why are non-GUE divers so interested in what GUE does?

 

[crofrog]

I said 5. DIR- GUE - Why are non-GUE divers so interested in what GUE does?

Sure sorry. 5 miles in minutes is 10mph, that’s not happening in a non tidal current outside of the artic

 

[kensuf]

Believe me or not, I don't really care. There were six of us on that dive, I don't think any of them are on scubaboard to verify it.

It was actually the summer of 2020, not '21. The captain gave us a 600' lead and we dropped to 140' in 70 seconds, but we nearly missed the wreck (Hydroatlantic, 330' long) because we were already past the stern by the time we got down there. Thankfully we were able to hide from the current behind the wreck and claw ourselves back on. Our exhaust bubbles were sucked downward into the holds, it was easily the wildest dive I've done down there.

The summer before that I watched as @LandonL tried to hook one of those 3' diameter float balls onto the same wreck and it got sucked down to 70'.

 

[jadairiii]

I said 5. DIR- GUE - Why are non-GUE divers so interested in what GUE does?

Drifting 5 miles is not very GUE/DIR, when properly in trim the current goes right around you.

 

[PfcAJ]

I’ve drifted a good ways too. Happens.

Drifting 5 miles is not very GUE/DIR, when properly in trim the current goes right around you.

that doesn’t make sense. Unless you’re working against it, you’re going to drift with it. There’s no mechanism to make you stationary or slower than the surrounding water without you putting some sort of effort into the equation be it finning or scootering.

 

[kensuf]

I’ve drifted a good ways too. Happens.

that doesn’t make sense. Unless you’re working against it, you’re going to drift with it. There’s no mechanism to make you stationary or slower than the surrounding water without you putting some sort of effort into the equation be it finning or scootering.

I think he's joking.