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

This come from a prev. thread. Why it is not advisable to start using travel gas, going up, with a ppO2 of 1.6 @ 40m? Isn't this same ppO2(1.6 of your choosen depth eg 50%@21m) in all water coloum, the most important is that you are at rest and that your CNS is not high . Can you please explaine why? Also anyone here uses such pratice ?
 

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I have always gas switched at 1.6 for deco at what ever depth that is for the gas. The only thing I was ever taught was to avoid a masive jump from a low pp02 to a high pp02 which can result in an O2 spike these can triger a cns hit.

If you are doing a big gas switch the prefered method is to switch to the new gas for 1mins and then switch back to the bottom gas for 1 min and then back on deco / travel mix. I have no idea if this makes a blind bit of diferance but that is the guidance I have read up. Personaly I like to try and keep the PP02 above or as near to 1.0 as possable during the deco stage of the ascent.

Some of the boys on the Delta team aparently use a small pony of 50% as an intermediate mix and a 28% travel gas. They use 70 or 80% for deco and they are doing up to 80m dives with 180min+ run times. I dont think they bother on the shallow stuff (60m)


Some cave divers are switching to 100% at 9m PP02 1.9 to improve off gassing but they are in perfict conditions with 0 swell and 0 current to worry about.

I have never herd any comments or read anything saying that 1.6 pp02 gas switching was a bad thing.

ATB

Mark Chase
 

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Andy[/quote]
[b said:
Quote[/b] ]
Oh, and the only need for a travel gas is in the 100 metre range, and usually only in cave diving.

Andy
Andy you have said it again? I cant understand this I thaught it was a typo the first time.

You cant do a 70, 80 ,90m dive without travel gas. For starters your back gas is not life suporting on the surface as its below 16%02 and apart from that you need to step your deco to prevent 02 spikes.

To do a dive over 70m without travel gas is stupid. to do one between 50 and 70 is nopt my prefered option either but after 70 its is dangerous.

What on earth are you basing this argument on?

How would you plan a 80m dive without travel gas?

I have to say you say some very strange things sometimes but this is by far the strangest. I am hoping that there is some twist in the tail some sermantics which can explain the statement?

I wait with baited breath

ATB

Mark Chase
 

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DIR Doctrine states that all dives below 30m should be done on Trimix. I then assume that max END would also be 30m (3.16bar N).
If my reasoning holds, a dive to 50m shold be done on at least a 20/30 mix or therabouts. This is a normoxic trimix with a max PPN of 3bar and PPo2 of 1.2 bar @ 50m.

To go much further you need to reduce the o2 content of the mix.

A 16/30 would take you to 60m with a PPo2 of 1.12bar and a PPN of 3.78bar. END of almost 28m, within acceptable limits.

To go to 70m and keep a PPo2 under 1.2bar (most would prefer it a bit lower until the ascent stage of the dive AFAIK) you would need to drop the o2%age to about 14%.

This is a hypoxic gas mix and will not sustain life on the surface. Therfore IMO a travel gas is definately going to be required.

I'm not a trimix diver (yet) so the mixes i've discussed may not be the mix of choice for most trimix divers, the ppo2 limits i've chosen may also not be the most popular but you cant argue the maths.
I've also not considered divers who hold their breath until they hit 10m so as to forgo using a travel gas for the obvious reasons. ie, they're mad.


Please feel free to pick apart my argument but i'm with mark on this one.

Stu.
 

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[b said:
Quote[/b] (wetlettuce @ Sep. 25 2003,00:20)]
[b said:
Quote[/b] ]1. The 15% mix is breathable at .5 mtr ie .15*1.05 = .16 so were exactly are you 'travelling'? There’s plenty of air to breathe at the surface and a couple of deco stages too.
This shows your total lack of understanding of trimix diving.

You’re kitted up with over 150lb of equipment on you are standing on the back of the boat that’s rocking and rolling waiting for the go. Your panting like a dog with the heat and the effort. Your breathing back gas to avoid breathing diesel fumes. Then you jump and if you’re first in on a short slack window you are regularly fining against a current to get to the shot. Normally by the time you get to the shot you need a min to compose your self.

Try that on 15% o2 and you could easily pass out

Try it on 10% and You will pass out more than likely on the boat but if you do manage to get in the water you could drown.

Try breathing of a helium J to see how long you will last on a non life supporting mix. Pete lasted three breaths and hit the floor like a sack. He said he had no warning he was just gone.
Hypoxia is dangerous stuff.

[b said:
Quote[/b] ]2. Depends on how you define a spike with a change from around .465 (I did the math in another thread) to 1.6 especially when you consider a slow ascent of 3mtr/min and deep stops from 75% of max depth, but that’s DIR as I understand it. (calculations based on 15/55)
As I said semantics: You are using I assume 100% for deco and a 50% or 35/25 DIR mix for mid deco. We call that a travel mix. You are calling it a second deco gas. That’s fine but it is just semantics.

[b said:
Quote[/b] ]
Your technique differs in that the spike is less (from .75 to 1.6) although the penalty is that it is conducted significantly deeper and with more deco obligation.
The DIR training manual Getting Clear on the Basics written by Jarrod Jablonski Page 113.

Deco Mix:   50% 02    Gas switch Depth 21m  PP02 1.6
Deco Mix:  35/25 Mix  Gas Switch Depth 36m  PP02 1.61

_
The DIR training manual Getting Clear on the Basics written by Jarrod Jablonski Page 63.

PP02 0.16 = Hypoxic Danger Zone
PP02 0.10 = Unconsciousness and death become very likely
___

For 0.16 read 16% o2 at the surface
For 0.10 read 10% 02 at the surface


So JJ recommends a switch at 1.6 and I switch at 1.6. He considers 16% 02 in the Mix to be a Hypoxic danger Zone and so do I


[b said:
Quote[/b] ]Your technique differs in that the spike is less (from .75 to 1.6) although the penalty is that it is conducted significantly deeper and with more deco obligation.
Significantly ? JJ swaps at 36m I switch at 40m and we are both on 1.6pp02

I have 14mins less deco obligation than someone using 50% and 100% in my last example and if the diver is using 35/25 and 100 and I was using 32% and 100% He would have 117mins of deco after 30min at 70m and I would have 98mins.
If you ignore the helium in his deco mix I would have 98mins and he would have 99mins using a 20/85 profile


[b said:
Quote[/b] ]Calm down Mark, no ones 'stupid' or 'strange' just because they say something you don't agree with and because its not in a TDI manual. You'll only start a heated argument rather than a constructive debate.
Its not in my TDI manual, my DIR Getting Clear on the Basics and Beyond the Daylight Zone DIR cave diving manual, My INTD manuals, Kevin Gurrs Technical Diving manual or any of the dozens of other books I have read on the subject.

I wanted clarification of your statement. I now have it and in conclusion you are dangerously wrong on the issue of Hypoxic mix diving, wrong on the issue of depth for gas switches and deco commitments and arguing semantics on the use of the term travel gas.

I am not angry and I dont think you are stupid at all I think you have just misunderstood the books you have read on diving you haven’t done yet and probably have received no formal training on.

Sorry if that sounds harsh, I dont want to offend you for the sake of it, but you have to realise that these forums are open to any one to read and it important that people are properly informed on these potentially dangerous issues.


ATB

Mark Chase
 

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<font color='#000080'>
[b said:
Quote[/b] (wetlettuce @ Sep. 25 2003,10:41)]I'm giving up. Everyone do it Marks way, he is completely right and I am completely wrong.
Does that mean we may see the start up of Doing It Chase?
 

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Hands up the first person who's willing to proudly proclaim at a dive site "I'm a DIC"
 

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[b said:
Quote[/b] (MATTBIN @ Sep. 24 2003,11:56)]Well, it looks to me like one of you guys is wrong.
Looks like they are getting caught up on terminology to me, specifically the definition of travel gas.  It would appear to me that WL and GI3 are defining travel gas to be a cylinder of whatever, dedicated to the purpose of travelling and no other, whereas Mark is defining travel gas to be stuff you breathe whilst your back-gas is hypoxic.

Thus given the following; 10/50, 50% and 100%, (ie. something close to DIR standard gases) if you start off on the surface breathing 50%, descend to 10m and switch to back-gas, do the dive, switch back to 50% at 21m, and 100% at 6m.

I suspect one side would claim you were using 50% travel gas, whilst the other side would claim there was no travel gas since you are just using your deco gas.

Corrections anyone?
 

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I might be horribly out of date here, but I think this might just be a problem of terminology. When I started mix diving divers sometimes carried back gas (hypoxic at surface or just about), a deco bottle (>60% O2) and then a bottle of travel gas (between 21-50 % O2). The fashion now seems to be to simply carry two bottles of deco gas (>50% O2) to offer redundancy. Makes sense to optimise both side-bottles for deco, as any mix >20% or so will get you deep enough to use the back gas. So although the deco gas is used for travelling, it is only used to travel down a few metres rather than half way to the site. Also, as said above, avoids the problem of O2 spike when switching back off the back gas.
 

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[b said:
Quote[/b] (wetlettuce @ Sep. 25 2003,10:41)]
1,2,3,4,5,6,7,8,9,10

ahhhhhh

OK lets discuss this calmly



[b said:
Quote[/b] ]IMO this tunnel vision is too much. It is highly unlikely that you need any of your gas before your descent. Even on a 10/70 mix (which is well beyond this discussion) you can simply breathe from your 50% bottle for the first 6 mtrs. I'd prefer on that dive to take a stage of 10/70 therefore reserving my backgas for problems. And to take a gas on a dive with which you cannot receive full benefit from is not optimal. It works, but is not optimal, and thats the reason behind all DIR.
The irony of the tunnel vision commet is great


The simply breathing from your 50% before reaching normoxic depths clasifies this as a travel gas in the true sence of the word. As I said the term travel is used in the trimix world of OW diving to discribe a mix for off gassing used on the deep stops up to shallow deco gas depths. So as long as you ar NOT promoting using 15/45 trimix to breath on the boat , getting inn and finning to the shot we are in agreement if not using the same terminolagy.

[b said:
Quote[/b] ]I don't just make stuff up. I read and read and then read again until I understand, its just the way I am. I'm the ultimate doubter and cynic and so far the only diving style/system which has answered my questions properly is DIR.
Unfortunatly GI3 makes shocking statements and uses language in extreems to publicise the DIR movement. He has been found to be very mistaken and very bias in several of his published articals but that dosent seem to stop him ranting on.

How can you make a statememt like there is no need for travel gas in OW diving when there are loads of divers diving hypoxic mix depths out there.

Might I sugest that you read more of JJ's stuff which is far more ballanced and calmly writen without being any less DIR

Also read again what he has writen: The emphasis on the artical is on 02 spikes. This is what hapens when you switch from a very low PP02 to a very High one. If you keep the PP02 up you avoid spikes. The practice of repeating gas switches is also used to avoid spikes when the logistics of the dive force big diferentials in PP02 to be used.

This has nothing to do with DIR. I just dont think you would find many DIR divers doing a 15/45 bottom mix and using 50% and 100%for deco comming up from 70m.



[b said:
Quote[/b] ]PS Mark, I've told you a million times mate, do not exaggerate
We've all jumped off boats with twinsets and stages, and its not nearly as you describe. Go ask George, he'll put you straight. I'm giving up. Everyone do it Marks way, he is completely right and I am completely wrong.
No we all havent jumped of boats with twin sets let alown + stages and No I have not exagerated anthing. Many times I have strugled to keep ballance on a boat in full kit and several times through this summer I have been fully kitted up in 30c sweating my nutts of and breathing hard with the effort.
And because Andrew and I are often first in I am often swimming against the current to get to the shot.

I actualy used JJs books to back my arguments in my last thread so I am disapointed you decided to say it was MY way of diving. It is a commonly used termonalogy and a commonly used method of diving and most certianly not My way.

Also I beet you to it on DIC but I called my diving school DIM

Do it Marks way.

Mark Chase
 

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Sorry, DIM is taken already by the Doing It Minimal school of thought
 

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[b said:
Quote[/b] (wetlettuce @ Sep. 25 2003,12:37)]
[b said:
Quote[/b] ]My settings were GF of 1/90 which ensures that the stops start at 80% of the ATA's and the ascent rate is 3mtr/min. I do not include helium in Jplan as it penalises the diver for using it. That would result in a longer deco than was necessary particularly for dive 1 which would skew what I am trying to say.
If you used DIR's Decoplanner you would see that you cant use 1% as GF low. The lowest GF you can use is 5%. It wouldent make any diferance the deep stop would stay at the same depth.

All deco planning softwhere penalises the diver for using it in a deco mix. I dont think they do it for fun I think they do it because thats the way He works but GI3 & JJ are doing some cutting edge stuff where they ignore the helium.

Helium bends are easily treated so the risk is not as bad as with N02. They can be delt with without the need for a deco chamber but they are very very painful.



[b said:
Quote[/b] ]
4. The CNS% for dive 1 is 66% whereas with dive 2 it is 68% therefore the po2 for the dive was overall higher again meaning a more efficient decompression.

5. The runtime of dive 1 is longer than dive 2 by 5 minutes, again this is better as you are in a very changable environment and in computer deco software terms dive2 is more efficient.
Most of the points you raised are fine but you have ignored the 02 spike on the switch from back gas to 50% and you have ignored the lack of deep bail out but you will argue thats what your buddy is for so I wont go into that.

I do have a slight problem in that when I run the profiles through DIR's Decoplanner it gives me a run time of 86mins using 15/45 and 35% and 100% and a run time of 92 mins using 15/45 and 50% and 100% so using 50% is actualy extending the deco by 6mins but I dont see that as a problem just a personal choice.

I think an eficient deco would minimise the time in the water so seeing as both profiles are run on 5/90GFs and the 35% deco profile gets you out of the water quicker surley it is more efficient??

[b said:
Quote[/b] ]6. You actually use less deco gas on dive 2 and so have more reserve should the rare occasion arise where you need to breath the 50% at the surface whereas if you end up breathing 35% gas at the surface you may not have enough for your deco, which screws the whole thing up. Gas consumption is important for the bottom gas on dive 2 but DIR dives the rule of thirds and maybe 15ltrs are required.
I would quite agree so use a drop tank or do as I do take a bigger tank of mix. 10ltr should do.



[b said:
Quote[/b] ]
7. Finally lets look at the dives as a whole. The use of 50% and 100% gets you out quicker, and also only introduces a 1.60 po2 at 21 mtrs which is safer by any stretch of the imagination as not only are you higher in the water column and closer to help you are also gas switching shallower and were are most cockups? At gas switches. The curve is smoother, the cns shows the deco potential of the plan is higher. If you look at both dives the runtime is equal at around 15 metres at 64 minutes and yet at this point on dive 2 you are breathing 50% with a higher po2, 1.25 compared to the 35% mix which is only .875. And now you start to do significant stops, just when you need a higher po2 to help your body release all that nitrogen you strangle it with a low po2.
I cant get my computer to make the 50% option quicker than the 35% option. I also tried it on V planner and got the same result. which kind of calls into question the whole issue of deco potential.

Whilst I applaud the use of 1.0+ ppo2 on the shallower section of the dive one must understand that the higher PPo2 on the deep section of the dive is equaly important in the planning of off gassing to affect the faster compartments. I dont honistly think there is much to choose between the two gas options each has its own benifit in the deco curve but my main reasions for not using them were not bassed on the deco curve. They were bail out and 02 spike.

The other point is that a CNS hit on a deep stop is not going to hapen if you are breathing the corect gas. My CNS loading at gas switch depth for 35% o2 is 13% on the dive profile you offer.

CNS hits hapen because of incorect gas switches at depth or at the 6m stop due to passing the 100% CNS limit in the wrong conditions.

As I said before 90+% of my UK diving is Trimix bassed 50m + diving. The vast majority of the trips I go on I am surounded by very experianced Mix divers. One of my best Diving freinds is on Team Delta who have been doing mix for over 20 years.

These divers are actualy doing the dives and I look listen and lurn. Most of all I ask questions. My personal choice in diving profile is from, study, training, listning and experiane. It would be outragous to claim that it was all MY WAY so please dont make that mistake.

When you taklk to these divers and here the storys of the incidents they have been involved in over the years you can see why their gas planning takes into account a bit more than the beautiful simitery of the deco curve.

This thread got started because of a misunderstanding over ther diferent use of the term travel gas. Thats about it. I described your plan as dangerous because you intimated you would not use an intermediate gas on a deep dive. I then discover that you are using an intermediat gas you just prefer not to call it travel gas. Then it diversified into a discussion I hope about the choice of deep deco / travel gas you would use and why. I hope I put my case clearley. And in the light of the fact you are planning to use a gas other than back gas to start the dive and end the dive up to 6m I retract my comment whole hartedley.

ATB

Mark Chase
 

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Discussion Starter · #15 ·
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<font color='#0000FF'>Hello guys,

I checked a little bit about DIR gasses ( not to flame but trying to learn) I did 2 profile for the Famous 70m dive with 25min bottom time using Proplanner with 10% safety 20% microbubble formation and this is what I got.

If I plan a dive I would have used this gases 17/38 bottom gas, with 32% and 60% with a 1.4ppO2 at depth of 1.4 and END of 35m

[b said:
Quote[/b] ]Depth1=  70msw:  25mins 17%O2 38%He  Run Time= 25mins

  DIVE 1 DECOMPRESSION REQUIREMENTS      
   Stop=  48msw:   1mins 17%O2 38%He  Run Time= 28mins
   Stop=  38msw:   1mins 32%O2  0%He  Run Time= 30mins
   Stop=  27msw:   1mins 32%O2  0%He  Run Time= 32mins
   Stop=  24msw:   1mins 32%O2  0%He  Run Time= 34mins
   Stop=  21msw:   1mins 32%O2  0%He  Run Time= 35mins
   Stop=  18msw:   4mins 32%O2  0%He  Run Time= 39mins
   Stop=  15msw:   4mins 60%O2  0%He  Run Time= 44mins
   Stop=  12msw:   6mins 60%O2  0%He  Run Time= 50mins
   Stop=   9msw:   9mins 60%O2  0%He  Run Time= 59mins
   Stop=   6msw:  53mins 60%O2  0%He  Run Time=112mins

     Total time to surface=88mins              
     Time to first stop=5mins                  
     CNS exposure: 49%peak, 49%dive end        
     CNS exposure= 49%                          
     Max PPO2=1.53bar  OTU=138units  OTUtotal=138
     Dive Start:   Day 1   Time 00:00        
     Dive Finish:  Day 1   Time 01:53        
     Flight Time:  Day 1   Time 10:30
     Surface gas=21%O2,  0%He
     Surface interval=   0mins                    
********************************************************************************
 Depth1=  70msw:  25mins 17%O2 38%He  Run Time= 25mins
 Depth,    Gas,  Stop,  RT
     6,  60/ 0,    53,   112
     9,  60/ 0,     9,    59
    12,  60/ 0,     6,    50
    15,  60/ 0,     4,    44
    18,  32/ 0,     4,    39
    21,  32/ 0,     1,    35
    24,  32/ 0,     1,    34
    27,  32/ 0,     1,    32
    38,  32/ 0,     1,    30
    48,  17/38,     1,    28
Then I got in an other DIR site as I am not competent enough on DIR and suggested a 15/55 back gas and 50% and 100% and this is what I got

[b said:
Quote[/b] ] Depth1=  70msw:  25mins 15%O2 55%He  Run Time= 25mins

  DIVE 1 DECOMPRESSION REQUIREMENTS      
   Stop=  50msw:   1mins 15%O2 55%He  Run Time= 28mins
   Stop=  40msw:   1mins 15%O2 55%He  Run Time= 30mins
   Stop=  33msw:   1mins 15%O2 55%He  Run Time= 32mins
   Stop=  30msw:   1mins 15%O2 55%He  Run Time= 33mins
   Stop=  27msw:   2mins 15%O2 55%He  Run Time= 35mins
   Stop=  24msw:   5mins 15%O2 55%He  Run Time= 41mins
   Stop=  21msw:   3mins 50%O2  0%He  Run Time= 44mins
   Stop=  18msw:   4mins 50%O2  0%He  Run Time= 48mins
   Stop=  15msw:   5mins 50%O2  0%He  Run Time= 54mins
   Stop=  12msw:   9mins 50%O2  0%He  Run Time= 63mins
   Stop=   9msw:  12mins 50%O2  0%He  Run Time= 75mins
   Stop=   6msw:  54mins 99%O2  0%He  Run Time=129mins

     Total time to surface=105mins              
     Time to first stop=4mins                  
     CNS exposure: 110%peak, 110%dive end          !! CNS WARNING  !!
     CNS exposure=110%                          
     Max PPO2=1.58bar  OTU=188units  OTUtotal=188
     Dive Start:   Day 1   Time 00:00        
     Dive Finish:  Day 1   Time 02:09        
     Flight Time:  Day 1   Time 11:47
     Surface gas=21%O2,  0%He
     Surface interval=   0mins                    
********************************************************************************
 Depth1=  70msw:  25mins 15%O2 55%He  Run Time= 25mins
 Depth,    Gas,  Stop,  RT
     6,  99/ 0,    54,   129
     9,  50/ 0,    12,    75
    12,  50/ 0,     9,    63
    15,  50/ 0,     5,    54
    18,  50/ 0,     4,    48
    21,  50/ 0,     3,    44
    24,  15/55,     5,    41
    27,  15/55,     2,    35
    30,  15/55,     1,    33
    33,  15/55,     1,    32
    40,  15/55,     1,    30
    50,  15/55,     1,    28

At the END what I got was DIR 129 runtime as opposed to 'normal' of 112min which is 17min more. Also DIR CNS is 110% as opposed to 49% which is 61% CNS difference, which is quite a lot. As nearly everywhere a rule of thumb is to use wright tool for the wright job, which is best gas. Why only deco gasses we have to use best mix and in bottom no? Have I screwd the DIR gasses? Have I calculated something wrong?
 

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Discussion Starter · #16 ·
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<font color='#0000FF'>Hello WT,

[b said:
Quote[/b] ]Although there is no real option for the slightly deeper plan so I hope you are sure about the depth
What did you mean with the attached quote, I didn't understand  


WT I am not saying that 'mine' is better, just remember that here in Malta technical diving is at it's start and here there aren't so many divers to ask to or compare with! Also I always used Prodive Planner as I was teached this way by my both TDI inst. So you think my profile is very agressive? Can anyone here, especially Mark (as he uses Proplanner) compare this dive with his software. Me and my friends did a lot of dives with such programms without any incident and feeling well after the dive.
 

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Actualy I use Decoplanner rather than Proplanner as I find the interface much easier to work with. The results are very similar.

I dont think the profiles are agresive and I also know that in Malta 60% for max 02 deco is normal so there is no point mentioning an improvement there

Obviously it is pointless using 50% and 60 % for deco so the maximun benifit for your plan would be a mid range gas around the 30%mark

In all this talk of profiles dont loose sight of the other benifits of low 02 deco gas, like bail out and spike.

GI3 comments in the artical Andy put forward are his normal Black and white agresive aproach but if your looking at a pure deco profile obviously something like 30% 50% and 100% would be ideal. The only answer is to use a CCR and maintain a constant PP02 of 1.4 through the dive and deco up to a switch to 1.6 at the shallow stops.

It is a compromise using 32%. I havent been able to enter 80% into the argument because it is so anti DIR but on my choice of profile I have 32% and 80% so I get to do the longer 10m stops and up on a high PP02 where as on 100% I am doing long stops at 9m on 32% which is obviously not ideal.

My last stop on 32% would normaly be 15m with a PP02 0f 0.8 I would then go to 10m and switch to a pp02 od 1.6 on the 80% so out of 69mins of deco I would spend a total of 62mins above 1.0 pp02 and my lowest pp would be 0.8

It has made the argument a bit more complicated running the 32% up to 6m.

ATB

Mark Chase
 

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I could be wrong, but I believe DecoWeenie runs with "Helium is your friend" and therefore you're better off telling it you're using Helium to get shorter deco.
I can't test that at the moment tho as my Palm is buggered..
 

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[b said:
Quote[/b] ]I also don't think the profiles are aggressive although I thought it best to point out why the profile was shorter and also to point out the GF's which match your proplanner settings. Mark, in the past has said that a GF of 100 was aggressive but now it isn't. Ah well.

I cant see where he is using 100% GF it didnt look like 100% on my Decoplanner table when I did a comparison. He was using a 10% safety and 20% microbubble profile which give a 20% GF on the deeper stops but I couldent see the 100GF bit.

Yes I would consider a 100% GF agresive for a 70m dive and I havent changed my view. If Perre's profile is 20/100 it has been modified by the softwhere due to the safety factors he has put in back down to about 70% Hi by my comparason.

On profile 1

To get the deep stop I had to set the GF low to 10% and to get the 6m stop to 47mins (His was 53)I had to set the high to 70%.

Deco planner total deco time was 82min running 10/70GF
Running 20/100 it was 54mins. So I realy dont think it is a 100GF profile he posted. His run time was 88mins.

I dont have Proplanner on the desk top PC as I dont use it much and I cant be assed to run it through the VR3


ATB

Mark Chase
 

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[b said:
Quote[/b] (wetlettuce @ Sep. 25 2003,15:56)]Georges comment was about spikes at depth and tox's at depth. For his dives I am sure 36 mtrs is shallow but the trend is still the same and given the choice I choose dive no2 on my earlier post. I've never been shocked by Georges stuff and there really isn't a lot of JJ's stuff which covers this. Mistaken and biased? What could that be about? An inspiration article which was true when he wrote it but is paraded out every time someone wants a pop at him? And of course he's biased, we all are, including you.



PS and someone at least did see the answer in my PS earlier and sent me a PM. Remaining nameless
[b said:
Quote[/b] ]"I wait with baited breath" is a way round the hypoxic mix argument.  You just breath surface air and hold your breath until you get to a depth that your gas is safe at.
I dug out JJ's books this morning.

Getting Clear on the Basics (The fundimentals of technical diving)

Has 9 chapters on this subject covering Decompresion Mechanics, Ox Tox, Alternitive breathing gasses and the Logistics of diving Mix other than Air.

The book is an excelent training manual for technical diving and is available to down load off of the GUE web site.

Well worth a read

It would be easier to list the non controvirsial articals that GIT has written. His 80/20 artical has been ripped apart his CCR artical is famousley inacurate and he says things like cave diving is proper diving, and OW diveing is all bounce dives.  Comments made slagging off some of the worlds best divers dont help with his image much. He obviously loves his caves and has a low reguard for OW diving but his inflamitory comments and hyper agresive aproach is always going to have him slagged off.

ATB

Mark Chase

No comment on the 100% GF factor yet? Your not becoming a bit GI3 are you? Slag people off without reserching the data first puerley on the basis you consider them lesser divers as they are not DIR ?

ATB

Mark Chase
 
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