VR3 BUH or VPM

zabierek · 25th April 2008, 12:08

Hi Guys,

Decompression profiles is just nothing more than profiles. Some kind of mathematics that works: one best for one, second best for others.

I was dive technicaly form about 10 years, and as all we know, profiles we use 10 years ago was slightly different. But it also works... I have never serious DCS hit (diving commonly 4C temp. water) on Buhlman profiles, on GF profiles, on VPM profiles, but sometimes I feel terrible after a dive - doesnt matter what kind of profile I used. Sometimes also after this same profile my buddy feel terrible or was bent when I feel beautiful... So - it means - this is just depended of many, many more factors than just priofile.

Just to put something from my side to this discussion lets compare models we discuss to AB2 (COMEX one).... This will be very, very interesting

**aainslie** · 25th April 2008, 17:19

Just to be clear - the dive mentioned above was using VPM before the implementation of B. Profiles on VPM-B are more conservative than under pure VPM. And just as no-one dives the original Haldane or even Buhlmann, no one dives VPM.

So please let's compare apples to apples. Either one decides that for some strange purist reason one can ONLY consider the original version of models, in which case one should compare pure Buhlmann or even better, Haldane (NO GF's allowed) to the original VPM, OR one should compare VPM B to Buhlmann GF. Picking one's battles by comparing the original VPM to GF-modified Buhlmann makes no sense.

And on that point - so what if someone got bent on VPM? We all know that. We also know that Haldane and original Buhlmann have pretty high risk. That's why none of us use any of them.

On the issue of whether the change was justified empirically or theoretically - in most cases, science advances by using each to inform one's application and usage of the other. IMHO it's silly to argue whether B was modified for theoretic or empirical reasons.

Serge · 27th April 2008, 01:06

Quote: (Originally Posted by tecdivertraining)

... I respect all the opinions in this thread and only agree with a handfull, but remember this what works works, and when training new students in deeper diving techniques its essential to build confidence in procedures, threads like this with overloaded post from the software author create lots of confusion, already this week the chap taking his class with me is unsure he wants to dive using V-planner having read all this, totaly his call, as an educated diver...

The software author is hardly responsible for this. This is a direct result of a "vast ani-VPM-wing conspiracy"

peppered with an ample dose of unsubstantiated fear tactics. You should ask the student, where in this thread is the question raised about how many divers were bent on Buhlmann? I think that's only fair. Surely, anyone can clearly see through this charade for what it's worth - mere speculation. Hardly a solid platform to base an opinion on a such important topic as this outside of the classroom. Don't you agree?

tecdivertraining · 27th April 2008, 01:49

Quote: (Originally Posted by Serge)

The software author is hardly responsible for this. This is a direct result of a "vast ani-VPM-wing conspiracy"

peppered with an ample dose of unsubstantiated fear tactics. You should ask the student, where in this thread is the question raised about how many divers were bent on Buhlmann? I think that's only fair. Surely, anyone can clearly see through this charade for what it's worth - mere speculation. Hardly a solid platform to base an opinion on a such important topic as this outside of the classroom. Don't you agree?

The point I was trying to make was directed at the author and his need to continually keep posting to aid his product and that it may not be doing anyone any favors, I have yet to read a post were kevin G, the Dive rite boys, or any other computer software guru has responded so many times on the internet to promote and defend thier product to issues surrounding the program if he didnt post their would be little or no amunition for the Vast anti-VPM wing as you so put it to jump all over his comments.

As for the students/class it just provokes unnecessary debates when theirs already a lot to get your head around. And i do agree that the need to highlight the risks of several platforms used for dive planning is essential in teaching a well rounded diver but the questions raised were directly referencing this thread and V-planner.

Drmike · 27th April 2008, 02:44

Quote: (Originally Posted by Serge)

peppered with an ample dose of unsubstantiated fear tactics.

Can you point to these as I cant find them.

**DeepBlueInnovation** · 27th April 2008, 02:57

Irrespective of whether I agree with a manufacturer's argument, I am grateful that they participate in these forums. I am also happier that they passionately support their product and would be more worried about the manufacturer who doesn't!

In as much as it relates to teaching, in my opinion it is the role of a teacher to focus a course in its necessary direction during the time available and to provide students with requisite information. As I see it if a student is distracting the class with topics that are not part of a course then you can ask them to discuss it with you outside class hours or refer them to a more appropriate venue for their discussion. I can see no more appropriate place to hold this discussion than Rebreather World.

Cheers,

Ben.

Quote: (Originally Posted by tecdivertraining)

The point I was trying to make was directed at the author and his need to continually keep posting to aid his product and that it may not be doing anyone any favors, I have yet to read a post were kevin G, the Dive rite boys, or any other computer software guru has responded so many times on the internet to promote and defend thier product to issues surrounding the program if he didnt post their would be little or no amunition for the Vast anti-VPM wing as you so put it to jump all over his comments.

As for the students/class it just provokes unnecessary debates when theirs already a lot to get your head around. And i do agree that the need to highlight the risks of several platforms used for dive planning is essential in teaching a well rounded diver but the questions raised were directly referencing this thread and V-planner.

tecdivertraining · 27th April 2008, 03:30

Quote: (Originally Posted by DeepBlueInnovation)

Irrespective of whether I agree with a manufacturer's argument, I am grateful that they participate in these forums. I am also happier that they passionately support their product and would be more worried about the manufacturer who doesn't!

theirs participation in a professional manner and theirs slagging with a well respected hyperbaric doc, no need to be done in public.

Quote: (Originally Posted by DeepBlueInnovation)

In as much as it relates to teaching, in my opinion it is the role of a teacher to focus a course in its necessary direction during the time available and to provide students with requisite information. As I see it if a student is distracting the class with topics that are not part of a course then you can ask them to discuss it with you outside class hours or refer them to a more appropriate venue for their discussion. I can see no more appropriate place to hold this discussion than Rebreather World.

Cheers,

Ben.

I kinda agree, Thanks for you comments.

Mike · 27th April 2008, 09:54

Quote: (Originally Posted by rossh)

.
WTF is this?? At the recent DAN conference you told some of your peers, that you *did* pass these incidents onto me. So which is it Andrew.. you contacted me or you didn't?

Andrew just said that he was sure that not everyone who he treated that was bent while diving V-Planner reported it to you, not that no incidents were ever reported.
And he's right.
Dr Fock treated me for a mild bend (couple of dips, but I refused the third when my lungs were more annoying than my shoulders) after I'd done 5 dives using VPMB over a weekend.
As it happened, I carried a sensus pro for the dives, so as part of the treatment Andrew compared my profiles to a couple of models to see if there was any gross stupidity on my behalf (there wasn't, but the profiles were slightly on the aggressive side of 'normal' - I think I'd planned at VPMB +1).

I can't actually recall as to whether I said how I planned the dives, or whether I just handed over the graphs.There was certainly no professional advice given to say the model was wrong, just a suggestion to compare different models, and perhaps increase the level of conservation, especially for multiple dives in series.

Only one data point, and from a few years ago, but it does support Gasman's assertion that not all incidences of DCS on VPMB are reported back to Ross.

Mike

**UWSojourner** · 27th April 2008, 15:18

Quote: (Originally Posted by Mike)

Dr Fock treated me for a mild bend (couple of dips, but I refused the third when my lungs were more annoying than my shoulders) after I'd done 5 dives using VPMB over a weekend. ... I think I'd planned at VPMB +1.

VPM has limited adjustment for repetitive diving which does add additional risk. Scaling up conservatism over a busy weekend of diving might be appropriate, especially if you're repetitively doing those dives that take VPM into that "no mans land" well above Buhlmann's gradients.

I'm not saying anything was your fault; this is solely a comment on VPM and what it does and doesn't do for you. [and before any VPM aficionados show up, yes I am well aquainted with the VPM "repetitive dive adjustment"

].

Simon Mitchell · 11th July 2008, 09:45

Hello,

I completely missed this, and have no interest in reigniting it now!

I just wish to point out that Peter Bennett and Bruce Wienke and I co-chaired a UHMS workshop entitled "Decompression and the Deep Stop" which took place in Salt Lake City over two days immediately prior to the UHMS Annual Scientific Meeting in June. This was attended by most of those with a research interest in this field including Hamilton, Brubakk, Gerth, Doolette, Blatteau, Jablonski, Neuman, Gutvik, Gault, Marroni and many others in addition to the chairs listed above. The participants debated many of the issues aired in this thread at an expert level, including the recent US, French and Norwegian research, the utility of anecdote as "evidence" in support of decompression algorithm validity, and how to move forward from here. There will be one or two statements expressing the workshop's consensus on the current situation that may be surprising to some. If you have been interested in this thread, you will find the proceedings fascinating when they become available. I will keep you posted on that as things progress (we have a lot of discussion to edit). Later this year is about all I can say right now.

Warm regards,

Simon M.

25th April 2008, 12:08	#181 (permalink)
zabierek New Member Current Rebreather/s: Inspiration Classic Megalodon Classic Kiss Other CCR Dolphin Other Rebreather/s: Other CCR Dolphin Join Date: Feb 2006 Location: Warsaw, Poland Posts: 40	Re: VR3 BUH or VPM Hi Guys, Decompression profiles is just nothing more than profiles. Some kind of mathematics that works: one best for one, second best for others. I was dive technicaly form about 10 years, and as all we know, profiles we use 10 years ago was slightly different. But it also works... I have never serious DCS hit (diving commonly 4C temp. water) on Buhlman profiles, on GF profiles, on VPM profiles, but sometimes I feel terrible after a dive - doesnt matter what kind of profile I used. Sometimes also after this same profile my buddy feel terrible or was bent when I feel beautiful... So - it means - this is just depended of many, many more factors than just priofile. Just to put something from my side to this discussion lets compare models we discuss to AB2 (COMEX one).... This will be very, very interesting __________________ ___ Tomasz Żabierek IANTD Trimix OC/CCR IT CCR Training all levels on HammerHead CCR, Megalodon, COPIS Meg, Inspiration/Evolution, KISS Rebreather, Dreager SCR Training worldwide in polish, english or russian language, website: www.hogarthian.pl
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25th April 2008, 17:19	#182 (permalink)
aainslie So Cal Tech Diver Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Apr 2006 Location: LA Posts: 197	Re: VR3 BUH or VPM Just to be clear - the dive mentioned above was using VPM before the implementation of B. Profiles on VPM-B are more conservative than under pure VPM. And just as no-one dives the original Haldane or even Buhlmann, no one dives VPM. So please let's compare apples to apples. Either one decides that for some strange purist reason one can ONLY consider the original version of models, in which case one should compare pure Buhlmann or even better, Haldane (NO GF's allowed) to the original VPM, OR one should compare VPM B to Buhlmann GF. Picking one's battles by comparing the original VPM to GF-modified Buhlmann makes no sense. And on that point - so what if someone got bent on VPM? We all know that. We also know that Haldane and original Buhlmann have pretty high risk. That's why none of us use any of them. On the issue of whether the change was justified empirically or theoretically - in most cases, science advances by using each to inform one's application and usage of the other. IMHO it's silly to argue whether B was modified for theoretic or empirical reasons. __________________ Andrew Ainslie
(Online)

27th April 2008, 01:06	#183 (permalink)
Serge New Member Current Rebreather/s: Evolution Other Rebreather/s: Join Date: Dec 2007 Location: NY Posts: 94	Re: VR3 BUH or VPM Quote: (Originally Posted by tecdivertraining) ... I respect all the opinions in this thread and only agree with a handfull, but remember this what works works, and when training new students in deeper diving techniques its essential to build confidence in procedures, threads like this with overloaded post from the software author create lots of confusion, already this week the chap taking his class with me is unsure he wants to dive using V-planner having read all this, totaly his call, as an educated diver... The software author is hardly responsible for this. This is a direct result of a "vast ani-VPM-wing conspiracy" peppered with an ample dose of unsubstantiated fear tactics. You should ask the student, where in this thread is the question raised about how many divers were bent on Buhlmann? I think that's only fair. Surely, anyone can clearly see through this charade for what it's worth - mere speculation. Hardly a solid platform to base an opinion on a such important topic as this outside of the classroom. Don't you agree?
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27th April 2008, 01:49	#184 (permalink)
tecdivertraining RebreatherWorld Sponsor Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Megalodon Ouroboros Dolphin Other Rebreather/s: Not Bought Yet Dolphin Join Date: May 2005 Location: Phuket, Thailand Posts: 462	Re: VR3 BUH or VPM Quote: (Originally Posted by Serge) The software author is hardly responsible for this. This is a direct result of a "vast ani-VPM-wing conspiracy" peppered with an ample dose of unsubstantiated fear tactics. You should ask the student, where in this thread is the question raised about how many divers were bent on Buhlmann? I think that's only fair. Surely, anyone can clearly see through this charade for what it's worth - mere speculation. Hardly a solid platform to base an opinion on a such important topic as this outside of the classroom. Don't you agree? The point I was trying to make was directed at the author and his need to continually keep posting to aid his product and that it may not be doing anyone any favors, I have yet to read a post were kevin G, the Dive rite boys, or any other computer software guru has responded so many times on the internet to promote and defend thier product to issues surrounding the program if he didnt post their would be little or no amunition for the Vast anti-VPM wing as you so put it to jump all over his comments. As for the students/class it just provokes unnecessary debates when theirs already a lot to get your head around. And i do agree that the need to highlight the risks of several platforms used for dive planning is essential in teaching a well rounded diver but the questions raised were directly referencing this thread and V-planner. __________________ Mathew Partridge Technical Director Pro-Tech Dive College www.protechdivers.com www.tech-ccr.com
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27th April 2008, 02:44	#185 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,325	Re: VR3 BUH or VPM Quote: (Originally Posted by Serge) peppered with an ample dose of unsubstantiated fear tactics. Can you point to these as I cant find them. __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
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27th April 2008, 02:57	#186 (permalink)
DeepBlueInnovation Learning to Kiss Current Rebreather/s: Not Bought Yet Other Rebreather/s: Prism Topaz Not Bought Yet Join Date: Sep 2005 Location: Perth, Western Australia Posts: 358	Re: VR3 BUH or VPM Irrespective of whether I agree with a manufacturer's argument, I am grateful that they participate in these forums. I am also happier that they passionately support their product and would be more worried about the manufacturer who doesn't! In as much as it relates to teaching, in my opinion it is the role of a teacher to focus a course in its necessary direction during the time available and to provide students with requisite information. As I see it if a student is distracting the class with topics that are not part of a course then you can ask them to discuss it with you outside class hours or refer them to a more appropriate venue for their discussion. I can see no more appropriate place to hold this discussion than Rebreather World. Cheers, Ben. Quote: (Originally Posted by tecdivertraining) The point I was trying to make was directed at the author and his need to continually keep posting to aid his product and that it may not be doing anyone any favors, I have yet to read a post were kevin G, the Dive rite boys, or any other computer software guru has responded so many times on the internet to promote and defend thier product to issues surrounding the program if he didnt post their would be little or no amunition for the Vast anti-VPM wing as you so put it to jump all over his comments. As for the students/class it just provokes unnecessary debates when theirs already a lot to get your head around. And i do agree that the need to highlight the risks of several platforms used for dive planning is essential in teaching a well rounded diver but the questions raised were directly referencing this thread and V-planner.
(Offline)

27th April 2008, 03:30	#187 (permalink)
tecdivertraining RebreatherWorld Sponsor Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Megalodon Ouroboros Dolphin Other Rebreather/s: Not Bought Yet Dolphin Join Date: May 2005 Location: Phuket, Thailand Posts: 462	Re: VR3 BUH or VPM Quote: (Originally Posted by DeepBlueInnovation) Irrespective of whether I agree with a manufacturer's argument, I am grateful that they participate in these forums. I am also happier that they passionately support their product and would be more worried about the manufacturer who doesn't! theirs participation in a professional manner and theirs slagging with a well respected hyperbaric doc, no need to be done in public. Quote: (Originally Posted by DeepBlueInnovation) In as much as it relates to teaching, in my opinion it is the role of a teacher to focus a course in its necessary direction during the time available and to provide students with requisite information. As I see it if a student is distracting the class with topics that are not part of a course then you can ask them to discuss it with you outside class hours or refer them to a more appropriate venue for their discussion. I can see no more appropriate place to hold this discussion than Rebreather World. Cheers, Ben. I kinda agree, Thanks for you comments. __________________ Mathew Partridge Technical Director Pro-Tech Dive College www.protechdivers.com www.tech-ccr.com
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27th April 2008, 09:54	#188 (permalink)
Mike Prism 'prentice Current Rebreather/s: Prism Topaz Other Rebreather/s: Inspiration Classic Evolution Join Date: Feb 2005 Location: Melbourne Posts: 329	Re: VR3 BUH or VPM Quote: (Originally Posted by rossh) . WTF is this?? At the recent DAN conference you told some of your peers, that you did pass these incidents onto me. So which is it Andrew.. you contacted me or you didn't? Andrew just said that he was sure that not everyone who he treated that was bent while diving V-Planner reported it to you, not that no incidents were ever reported. And he's right. Dr Fock treated me for a mild bend (couple of dips, but I refused the third when my lungs were more annoying than my shoulders) after I'd done 5 dives using VPMB over a weekend. As it happened, I carried a sensus pro for the dives, so as part of the treatment Andrew compared my profiles to a couple of models to see if there was any gross stupidity on my behalf (there wasn't, but the profiles were slightly on the aggressive side of 'normal' - I think I'd planned at VPMB +1). I can't actually recall as to whether I said how I planned the dives, or whether I just handed over the graphs.There was certainly no professional advice given to say the model was wrong, just a suggestion to compare different models, and perhaps increase the level of conservation, especially for multiple dives in series. Only one data point, and from a few years ago, but it does support Gasman's assertion that not all incidences of DCS on VPMB are reported back to Ross. Mike __________________ Open ....... Closed Mind ........ Loop
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27th April 2008, 15:18	#189 (permalink)
UWSojourner Pacific Northwest Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Feb 2005 Location: Portland Oregon Posts: 556	Re: VR3 BUH or VPM Quote: (Originally Posted by Mike) Dr Fock treated me for a mild bend (couple of dips, but I refused the third when my lungs were more annoying than my shoulders) after I'd done 5 dives using VPMB over a weekend. ... I think I'd planned at VPMB +1. VPM has limited adjustment for repetitive diving which does add additional risk. Scaling up conservatism over a busy weekend of diving might be appropriate, especially if you're repetitively doing those dives that take VPM into that "no mans land" well above Buhlmann's gradients. I'm not saying anything was your fault; this is solely a comment on VPM and what it does and doesn't do for you. [and before any VPM aficionados show up, yes I am well aquainted with the VPM "repetitive dive adjustment" ].
(Offline)

11th July 2008, 09:45	#190 (permalink)
Simon Mitchell New Member Current Rebreather/s: MK 15.X Other Rebreather/s: Join Date: May 2005 Location: New Zealand Posts: 177	Re: VR3 BUH or VPM Hello, I completely missed this, and have no interest in reigniting it now! I just wish to point out that Peter Bennett and Bruce Wienke and I co-chaired a UHMS workshop entitled "Decompression and the Deep Stop" which took place in Salt Lake City over two days immediately prior to the UHMS Annual Scientific Meeting in June. This was attended by most of those with a research interest in this field including Hamilton, Brubakk, Gerth, Doolette, Blatteau, Jablonski, Neuman, Gutvik, Gault, Marroni and many others in addition to the chairs listed above. The participants debated many of the issues aired in this thread at an expert level, including the recent US, French and Norwegian research, the utility of anecdote as "evidence" in support of decompression algorithm validity, and how to move forward from here. There will be one or two statements expressing the workshop's consensus on the current situation that may be surprising to some. If you have been interested in this thread, you will find the proceedings fascinating when they become available. I will keep you posted on that as things progress (we have a lot of discussion to edit). Later this year is about all I can say right now. Warm regards, Simon M.
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