Maximum END

[nilsdiver]

Yeah,actually I think they do care. (not about me as an individual but about divers in general)

From GUE.Com:

<<1.4 General Training Limits

The following limits apply to ALL levels of training (course specific limits can be found in the relevant sections).

1.4.2 END Limits

No dives are to exceed an Equivalent Narcotic Depth (END) of 100 feet (+/-30 feet)/30 meters (+/- 9 meters); END is established by the following equation = ((1-FHe)*ATAs)-1) * 33 (10m))) >>

Several years ago (when I was deco but not trimix trained) I asked Ocean Frontiers on Cayman (GUE Facility) about the possibility of doing some "tech" dives. The reply was that we could do extended dives but I could not go below 100 feet as I was not trimix trained.

The message seemed pretty clear,even without the course.

This is very odd. I'm looking at the 2006 version 4 of the GUE standards PDF. It says +-10 feet.

1.4.2 END Limits
No dives are to exceed an Equivalent Narcotic Depth (END) of 100 feet (+/-10 feet)/30 meters (+/- 3
meters); END is established by the following equation = [((1-FHe)*ATAs)-1) * 33 (10m)]
​

 

[ianr33]

I think that it's about recognizing the tradeoffs. Given the range of GUE diving, from recreational to miles back in a cave, I think that it's hard to make simple rules that are correct in 100% of the situations -- you would end up with far too complex or too many rules.

Yes, you could dive 32% a mile back into a cave, and yes you could dive helium, and might choose to for a lot of good reasons.

This is my whole point. I think that what constitutes a sensible mix at 100 feet very much depends on the conditions.

At one extreme the cold,silty,complex,bad viz cave certainly justifies Helium.

A lazy drift dive in Cozumel does not. Yet they are both covered by the same "rules"

To me it seems that DIR/GUE has very little flexibility in this area which is not realistic.

 

[Kim]

<snip>it's really a bit shallower if you want to keep to the new 1.2 PPO2 for cold water, <snip>

Is the PPO2 1.4 for warm water.....i.e. tropical....?

 

[Rainer]

This is my whole point. I think that what constitutes a sensible mix at 100 feet very much depends on the conditions.

At one extreme the cold,silty,complex,bad viz cave certainly justifies Helium.

A lazy drift dive in Cozumel does not. Yet they are both covered by the same "rules"

To me it seems that DIR/GUE has very little flexibility in this area which is not realistic.

What don't you understand about "standard mixes"? Having ONE gas for dives to 100' really does simplify a lot of planning. If you don't like it, don't dive it. Sounds like it isn't for you. That's ok. If you want to go to 130' on 27%, that's cool. It just isn't what GUE teaches. That's ok, too.

 

[Rainer]

Is the PPO2 1.4 for warm water.....i.e. tropical....?

For the working part of your dive, they teach to strive for 1.2 PPO2 (again, for average depth). That becomes a little less severe in tropical warm water MDL non-overhead dives. GUE teaches you to think about these issues and explains their reason for recommending 1.2. If you don't want to follow those recommendations, don't. If you'd like to better understand the "why", best to take a course and not learn to dive on the internet.

 

[Kim]

For the working part of your dive, they teach to strive for 1.2 PPO2 (again, for average depth). That becomes a little less severe in tropical warm water MDL non-overhead dives. GUE teaches you to think about these issues and explains their reason for recommending 1.2. If you don't want to follow those recommendations, don't. If you'd like to better understand the "why", best to take a course and not learn to dive on the internet.

I'm not learning to dive on the Internet - I took Nitrox years ago and understand the significance of PPO2 levels quite well. You mentioned it was a new limit for cold water. I was just curious as I thought the warm water limit at least was 1.4. That doesn't really demonstrate that GUE is so "inflexible" if they adopt different limits for different conditions, as appears to be happening here. (if my information is current)

As for me doing a GUE course. There's no point. I have no chance of creating a team here, or am I in a position to get the standard gases that GUE uses. I can only dive Nitrox when I travel, which I already have done for years!
Somehow I've managed to stay alive, and have to date never had any complaints that I screwed up anyone elses dive/vis...whatever.
As I take pictures I actually wish I could say the same about others.



Anyway - thank you for your post.

 

[Rainer]

As for me doing a GUE course. There's no point. I have no chance of creating a team here, or am I in a position to get the standard gases that GUE uses. I can only dive Nitrox when I travel, which I already have done for years!
Somehow I've managed to stay alive, and have to date never had any complaints that I screwed up anyone elses dive/vis...whatever.
As I take pictures I actually wish I could say the same about others.



Anyway - thank you for your post.

Listen, there are a TON of great non-GUE divers all over the world (duh). Again, this isn't a system for everyone. As for diving GUE in Japan, I know Bob Sherwood (Training Director) is there right now meeting up with some Tech 2 divers, so I know at least some exist!

 

[Rainer]

I'm not learning to dive on the Internet - I took Nitrox years ago and understand the significance of PPO2 levels quite well. You mentioned it was a new limit for cold water. I was just curious as I thought the warm water limit at least was 1.4. That doesn't really demonstrate that GUE is so "inflexible" if they adopt different limits for different conditions, as appears to be happening here. (if my information is current)

Again, it's not about "rules" and "limits". They're teaching what they consider safe diving practices. For them that means divers who understand where recommendations come from, and understand them well enough to know when and how to apply them. In more stressful situations (physically and psychologically), pulling back from a PPO2 of 1.4 can be beneficial. They believe 1.2 is going to maximize the chance of bringing you home. They're giving you tools and knowledge, then letting you go gain experience. That's the system.

 

[Kim]

Listen, there are a TON of great non-GUE divers all over the world (duh). Again, this isn't a system for everyone. As for diving GUE in Japan, I know Bob Sherwood (Training Director) is there right now meeting up with some Tech 2 divers, so I know at least some exist!

Stop being so defensive. I'm not attacking anyone, or trying to denigrate anything. I asked a simple question about the current GUE thinking on PPO2 limits in differing conditions.

As for Bob Sherwood - it wouldn't surprise me if he's staying in Thomas's house. They have a great JUE group going up in Tokyo. Unfortunately that's about 800 miles away from where I live, so not exactly of much help to me.
Further - the availabilty of nitrox varies from prefecture to prefecture in Japan. Up in Tokyo it's OK - trimix too. In Fukuoka where I am they don't allow it. There isn't a single place that can, or is allowed, to do the fills.

 

[limeyx]

This is my whole point. I think that what constitutes a sensible mix at 100 feet very much depends on the conditions.

At one extreme the cold,silty,complex,bad viz cave certainly justifies Helium.

A lazy drift dive in Cozumel does not. Yet they are both covered by the same "rules"

To me it seems that DIR/GUE has very little flexibility in this area which is not realistic.

It was my whole point too -- the rules "as written" seem very draconian (which I think is what starts a lot of the "discussions" on this board as people see something that looks very black and white, and really it is often shades of gray)

Have you taken GUE classes? You might find that in reality, the "rules" are more like guidelines to some extent, and there is indeed some flexibility.

Generally I am very reluctant to dive 32% past 100 feet, and I honestly wouldn't start doing it "because it's cozumel and it's warm and I can see all the fishies"

but when I was on Maui and 32% was too hard to get -- I dove air. Yes, to 100 feet.
And when I go on a boat here in SoCal that only fills air -- guess what? I get air fills. Even on top of 21/35 or 30/30 -- does that make me "non-DIR" cause I am diving a 21/20 mix?

Of course, every time we break the rules and get away with it, we are tempted to keep doing it. But the rules are not there for the dives that go fine -- they are there to help you when something goes wrong, which (hopefully) is not very often.

Like the other guys said, have you taken the classes? Because a *lot* of what you really get from GUE may not be written on paper or on slides, it's what you get in the class and diving with "mentor" divers.

You cannot learn to Dive or DIR dive on the internet.