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<font color='#0000FF'>Hello all,

Was going throght a EKPP website http://www.ekpp.de/training/030810-ressel.html and came across this training dive: Ressel (August 2003)

Deco schedule  
Depth Time Gas
55 40 tx 17/55
45 1  
42 1  
39 1  
26 1  (here ther is a misprint so count it as 36m)
30 1  
27 1  
24 1  
21 5 tx 50/25
18 2  
15 2  
12 5  
9 5  
6 15 oxygen

My question is how these guys who know what they are doing do so little deco for a 55m dive for 40min? ( I am not saying that they are doing something wrong...just to know better) I tried to simulate this dive on both Prolanner with 10% safety and 10% bubble formation and also tried to play with deco planner with varying GF but could not come close to their deco time! What deco prog. they use? Maybe if Dbus8 (i think) is here can he comment?
 

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A short fat well off crap cave diver. Likes wrecks
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Running deco planner on 20/100 GF you get 81mins of stops and they are doing 41mins?
Running 100/100 you get 62 mins of stops
 Their CNS would be 125% as well.

They are obviously ignoring the He in the deco gas which is a common thing amongst the DIR divers but even so its a very very agresive schedual and totaly unnecessary.

If you used 21/25 32% and 100% you could keep the deco down to 51mins and run a 20/100 profile. You would also only rack up 83% CNS

Long and short of it is it dosent make sense

ATB

Mark Chase
 

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hmmmm 32% and 100%.... kinda puts a nasty dip in your deco PO2 gradient.....

When you start digging into those DIR gas choices, they do have a good sound basis/reasoning. Must admit though, I think that deco schedule would exercise my sphincter ;)
 

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[b said:
Quote[/b] (zaksherlock @ April 18 2004,22:43)]hmmmm 32% and 100%.... kinda puts a nasty dip in your deco PO2 gradient.....

When you start digging into those DIR gas choices, they do have a good sound basis/reasoning. Must admit though, I think that deco schedule would exercise my sphincter ;)
Yes I personaly would run 32% and 80%. picking up the 32% at 39m. and swaping to 80% at 10m

Swaping from 17/55 to 50/25 at 21m is farrrrrrr more dodggy dont you agree? Going from 0.6 to 1.6pp02

If you go for the 21/30 - 32 switch you jump far less and the switch from 32 to 100 is the same as the jump from 17/55 to 50% so the argument falls a bit flat using their profile.

As I said its not the sort of profile I would like to attempt.

Is it DIR??? DIR standard gas for a 55m dive is 18/45 and the 50% deco gas has no He in it. These are not standard gas choice so are NOT DIR.  

ATB

Mark Chase
 

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<font color='#000080'>Hi

I am sure Michael has done enough dives to know what he can and cannot do with his deco. Its only a few minutes short of what we were taught on tech1, which is around 30/90 GF's although I might possibly move some of the stops and do more at 18 and 15 where the 50% is more beneficial and less at 12 and 9 as you are accelerating to the gas switch, but then I didn't do the dive and Michael and co didn't get bent so it just shows that the computers are rubbish and there are many ways to deco


As far as the gas being a DIR gas, we either have 18/45 or 15/55. The helium figures are minimums and you cannot really be that exact as it is preferred to be a bit generous with the helium. Its not as if it is practical to waste gas if you are a couple of points out. I would just dive the 17/55 as if it were 18/45 which is what I believe Michael has done.

Kindest Regards

Andy
 

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<font color='#0000FF'>Hello all again,

Let's keep this thread more friendly, I in now way want to critize any one DIR or not but want to learn more so let's keep to DIR or not out!

WL, did you do same profile in tech 1? As when I did mine we always used proplanner and now use deco planner as well but could not come close to this profile. I know that these guys know what are they doing or else would not be alive but I want to know how they decide or use a comp. programme to cut so much deco time. If Michael can replay would be very good as he would give a much in deatailed explanation. Or maybe you can ask other DIR divers and check what they think about such profile as me personally would find this profile too agressive compared to programms I use.
 

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[b said:
Quote[/b] (wetlettuce @ April 19 2004,10:52)]Hi

I am sure Michael has done enough dives to know what he can and cannot do with his deco. Its only a few minutes short of what we were taught on tech1, which is around 30/90 GF's although I might possibly move some of the stops and do more at 18 and 15 where the 50% is more beneficial and less at 12 and 9 as you are accelerating to the gas switch, but then I didn't do the dive and Michael and co didn't get bent so it just shows that the computers are rubbish and there are many ways to deco


As far as the gas being a DIR gas, we either have 18/45 or 15/55. The helium figures are minimums and you cannot really be that exact as it is preferred to be a bit generous with the helium. Its not as if it is practical to waste gas if you are a couple of points out. I would just dive the 17/55 as if it were 18/45 which is what I believe Michael has done.

Kindest Regards

Andy
Whilst I am sure Michael has vast experience with his personal limits I cant believe Tech 1 level diver would be running deco within a couple of mins of this profile.

Your guidance of ignoring what they are breathing?
?? and pretending its a different gas still doesn’t do much for their profile. The profile is definitely NOT 30/90. Its not even 100/100. That would give 52mins of stops on the pretend gas and 67 on the gas being breathed.

Using GUE's (DIR) Decoplanner Soft where.....

Running the profile on 30/90 using 18/45 as back gas, ignoring the He in the deco gas and running 50% and 100% for deco
You get 72mins total of deco which is 21mins more than they planned. Running the actual gas mix they are breathing you get 98mins of deco which is 57mins more deco than they planned.

If Tech 1 is shaving that sort of margin off of deco as standard someone is going to get them selves killed. Frankly I don’t believe it. This sort of profile is cutting edge and only for the super fit and super experienced. Posting it on a web site without background data is IMHO dangerous and irresponsible. Some idiot might try and copy it and end up in a wheel chair or worse.

I have no idea why divers feel the need to massively cut deco. They spend all that money on training, practicing and equipment becoming a safe diver and then risk paralysis or permanent sub clinical damage proving how dead hard they are getting out of the water before any one else. It’s a sad macho myth rather like 15 years ago when you were not a proper big man diver till you did 60m on air. Most of the 60 on air brigade are dead now and we think of them as mad to have attempted it. Lets hope the shaving of deco doesn’t take over as the big hairy balls thing to do in diving.

ATB

Mark Chase
 

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There is a theory who's basic premise is that by using relatively high percentages of He in your mid range deco gas you reduce gas counter diffusion and thereby reduce your deco commitment.

I can only assume this dive was done with the intention of testing that theory. The gasses chosen all seem to point to that.

I know we all love to have a pop at DIR (me as much as anyone). But, we must not forget that the WKPP in it's early days were pushing the limits of diving. The fact that DIR came out of that project is almost immaterial. It seems to me that these guys were doing just that - pushing the limits to see what is possible.

I have to say though, the deco they pulled seems like utter insanity to me, but the're out OK. I would love to know how they felt though, and to put a doppler on them to see how much gas was still fizzing around in there.

Andrew

Nope sorry, I've read it now, they did it as a normal dive, fair play to them. Not for me! Interesting the choice of 50/25. Somebody is way ahead of current theory with that one. I thought it was only a psychotic few who were doing this.

I guess the EKPP are well up, or even in advance of the current research, I had a chat with a Professor in UCL this morning about He on deco. this followed on from talking to Mark Eliyatt (not certain about my spelling) the chap who did the 300+M dive and his theories on deco.
He basically said that in some ways it is preferential to use He on deco, but, and it is a big but, there is no known data on the damage that it does to the human lungs, although it is known that prolonged exposure to high percentages (PPHe's) of He will cause damage to the alvioli. He has sent me a couple of papers which I should have when I get back from Egypt.

Andrew
 

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[b said:
Quote[/b] (Mark Chase @ April 19 2004,14:23)]Your guidance of ignoring what they are breathing?
?? and pretending its a different gas still doesn’t do much for their profile. The profile is definitely NOT 30/90. Its not even 100/100. That would give 52mins of stops on the pretend gas and 67 on the gas being breathed.


If Tech 1 is shaving that sort of margin off of deco as standard someone is going to get them selves killed. Frankly I don’t believe it. This sort of profile is cutting edge and only for the super fit and super experienced. Posting it on a web site without background data is IMHO dangerous and irresponsible. Some idiot might try and copy it and end up in a wheel chair or worse.
<font color='#000080'>Hi

Didn't give any guidance mate, only an opinion. Deco profile for single 50% deco was 55 mins not including the stops below 21 metres. EKPP profile is 21 minutes shorter but they used O2 at 6 meaning they could make that shorter, say by 11 mins which means a 10 minute difference. Depends I guess on your understanding of 'few'.

As deco is not an exact science I do not understand how you can say that they are cutting deco. We have talked previously about how the computers algorithms pad deco and do not treat helium correctly, or at least differently to how most recent research informs us. If you do not know the minimum or maximum with any accuracy because there are so many variables, then how can you say whether you are cutting or padding or just doing the correct deco? Its not just about time in the water, its about doing the deco in the right places and using the correct gasses and yes, some level of preconditioning.

I agree that one should not blindly follow someone elses deco profile. Anyone at that level of diving will have started with a baseline and with loads of experience will know what they can and cannot do over many dives.

Kindest Regards

Andy
 

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<font color='#0000FF'>Very interesting what these guys are doing. I think that future deco schedules and mixes will be born from the groundbreaking work EKPP, WKPP etc are doing, hats off to them big style.

However, in the meantime I will use my VR3, backup tables and spend a bit longer in the water, I like it in there.
 

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[b said:
Quote[/b] (wetlettuce @ April 19 2004,15:03)]
[b said:
Quote[/b] ]Hi

Didn't give any guidance mate, only an opinion. Deco profile for single 50% deco was 55 mins not including the stops below 21 metres. EKPP profile is 21 minutes shorter but they used O2 at 6 meaning they could make that shorter, say by 11 mins which means a 10 minute difference. Depends I guess on your understanding of 'few'.
I was referring to the bit where you said 'that’s what I would do' perhaps guidance was the wrong word. I have absolutely no comprehension of where you’re getting your numbers. The deco profile using a single deco gas of 50% and running 30/90 GFS (again I stress using DIR's Decoplanner soft where) would be 90 mins. That’s 215% more deco than they planned.


I don’t think that’s a little

I have been on boats where divers have missed 20mins of stops out of a 60min profile and got bent. These guys are shaving 50% off of accepted MINIMUM decompression profiles using tables not wrist computers. Such profiles can only be considered after lengthy build up periods where the limits are gradually pushed further and further back but the margin for error becomes non-existent.

Do you honestly think it’s worth it for the sake of another 20mins in the water?

I cant believe that very basic level technical training as offered in DIR Tech1 would expose divers to those sort of profiles as a mater of course.

People can do what they like it doesn’t bother me but its important that on open forums like this that someone points out how just how far off the map these chaps are.

Its worth noting that GUE the commercial wing of DIR do not even offer the option of running these sorts of profiles in their dive planning soft where. You can no plan a dive above 100/100GF or straight Bhulman using Decoplanner and you don’t get any reduction in deco for using He in the deco gas it loads up the deco like most other soft wear packages.

If GUE are so confident that their test data is correct and Bhulman was wrong, why does their Decoplanner system not reflect these developments?

[b said:
Quote[/b] ]As deco is not an exact science I do not understand how you can say that they are cutting deco. We have talked previously about how the computers algorithms pad deco and do not treat helium correctly, or at least differently to how most recent research informs us.
What computer? I was using straight Bhulman Tables on 100/100GF using ZHL16B tables

Had I used ZHL16C (computer based system) it would have given me 94mins of deco

If ZHL16B is considered a base line for deco and they are over 100% below that baseline I cant see any other description that fits apart from cutting deco.

I have run 40/90 and 50/90 profiles and I know how knackered I felt after the dives. Now I run 20/80 and I feel better. I have no doubt in my mind that if I ran the above profile I would get bent.

I will be very interested to see how your own personal deco profiles develop when you start running 45mn bottom times at these depths. Sub 30min profiles under 50m depths are easy and you can get away with murder but the clock really starts ticking after 50m and 40mins down there. Personally I noticed the difference straight away but then despite 9hours of badminton a week,  I am 40 and over weight so you might not feel it so acutely.

ATB

Mark Chase
 

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<font color='#000080'>Hi Mark,

like WL said (as Tech-1 divers) we would calculate the dive as needing 55mins of deco with a single deco gas (50%).  With the rule applied for also having O2 the EKPP profile is only 6mins short of what I would calculate for myself.

The proper use of deepstops (3m/min ascent from 80% of max ATAs up to 21m), the shape of the intermediate stops and proper use of the deco gas & O2 window is what makes this profile and others like it work.

Regards,

Mark.
 

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<font color='#000080'>
[b said:
Quote[/b] ]I cant believe that very basic level technical training as offered in DIR Tech1 would expose divers to those sort of profiles as a mater of course.
ROTFLMAO
 

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<font color='#0000FF'>
[b said:
Quote[/b] ]It’s a sad macho myth rather like 15 years ago when you were not a proper big man diver till you did 60m on air. Most of the 60 on air brigade are dead now and we think of them as mad to have attempted it.
Hey , i'm still alive and walking .

Now , i'm not going into the politics of trimix- hydrox etc etc , as most of you that have met me , get told that you lot know more about it than me , after doing all these modern day courses and progression in mix gas diving.

When i do the 60 mts on AIR, i have with me 2 7 lts stages

Left     34%  which i start sucking at 35 mts
Right 100 %  which i start sucking at   9 mts

Deco times are personal and VERY TOP SECRET


 

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<font color='#0000FF'>
[b said:
Quote[/b] ]I am 40 and over weight so you might not feel it so acutely.
Ling said you was CUDDLY not over weight  


It was me that said you wa a fat knacker
 

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[b said:
Quote[/b] (Andy the Commie 2 @ April 19 2004,19:10)]Deco times are personal and VERY TOP SECRET
<font color='#000080'>Hi

Thats probably because you forget and make it up each time LOL

Andy
 

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<font color='#0000FF'>NO Andy .

That are personally cut tables, in graph form,,,,,, in my jacket pocket
 

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<font color='#0000FF'>MArk and WL,

When you done tech. 1 , did you use Deco Planner for deco calculations? If yes what was the recommended setting to start with (gf's). Can you show here a dive planned for 55m for 40min using trimix, using 2 deco gases, so that I can actually compare with mine.
 

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Hi Dudes,

we are just diving our usual stuff. About the paralysis-risk..that would be the case if you fuck it up in the deep part.
By the way, this is where the VR3 kicks in...
i PERSONALLY know at least 3 guys with HEAVY bends (not only just Type I) after long and/or deep dives with the VR3.
I mean profiles like 80m for more than 1hour.
The deep-stops seem to be to shallow and to short and then the shallow stops can not cure that.
So go on have fun with the VR3 :)

But everyone should just go on and use whatever they find apropriate for their dives.
We get shorter deco a pure Buehlmann because the He-% is high enough and we keep pN2 and pO2 low.

About the gas-choices...
The He contents matters and the pO2 is second... standard has to be within the team.

We also sometimes do longer deco, but it is good to know who fast one can be out oft the water if needed.
There is really no hurry to race to the surface and so we usually do moderate times.
We think that deco can even be much shorter and we also play around with things like adjustable habitats and we will try this year a deco with only 2 longer stops involved...
Nobody knows if that will work....

We think it might be possible.
All the Coly-Dives in 2003 of every diver went to the Duke-University on a data-logger and the run the data against different models. So we also participate in sharing all our profiles with the University.

This has nothing to do with ego-macho-stuff.
The ego-macho-stuff is the 300m on OC with 1 Min Bottom-time stuff.
You just need to take the risk... thats all...
No skills, nothing...

Michael
 

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An interesting thread this.....

I was just about to reply saying "Michael will be along soon to give some first hand information" and saw his response.  Thanks for your input Michael.

Like I always say "your body needs to do the deco your body needs to do" and not some computer deco generated by some algorithm which bears little relationship to real life and real people.

Interesting thing about this is that they went and played tennis or something after the dive. The deco must have been good for them to do this.

Remember that Wally and the EKPP, WKPP and others are real people doing real dives.  The deco info from those dives is far more useful than any computer (which are often designed to "protect" your average resort diver who is smoking, drinking, overweight and unfit)

Everyone gets too hung up on comparing computer generated profiles and numbers.  It really isn't that exact.  You just need to "do the deco that your body needs to do"  That can take years to work out.
 
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