"re-assessing deco profiles and deep stops", plus other bits..

[rossh]

Ross, I chaired the consensus discussion that modified the draft statements.

I took the sentence from your UHMS proceedings report. It was given as the opening position on item two in the consensus section. The passage is spoken by you Simon. It does not mention a draft. However If that's in error, or you were reading from another's draft, then I'm sorry to have offended you.

Of course you are, but your criticisms need to be accurate. In putting two of your key criticisms (bubbles don't matter and the trial was about to invalidate itself) all you have succeeded in doing is showing that you are happy to speak authoritatively about things you dont understand. But if I was not here to point it out everyone would just believe you.

I didn't say "bubbles don't matter" How dare you! Now you owe me an apology.

I wrote: It might be a small distinction, but its an important one. High bubbles grades are associated with higher decompression STRESS. Not to be confused with (risk of) DCS [opinion Rossh]. You can have high decompression stress, in a stabilized condition, without the occurrence of DCS [opinion Rossh]. For this to progress into DCS, takes some additional conditions (which no one really knows what).

I believe that is what we see in the Blatteau studies, and numerous others. Normal decompression in progress. I believe microbubbles have been a normal part of normal successful diving since man first started [opinion Rossh]. There have been very few studies that show conditions in normal successful dives, or comparative testing of different successful ascent concepts, relative to deep stop techniques used today.

Yes, the NEDU study (or part of it) was about to be invalidated if it continued. As set out in the studies own limiting criteria. The lower test limit was about to be breached in a few dives. Wayne Gerth "So we also wanted to reject low, if any of the profiles got to less than 3%."

I have, in fact, agreed with all the commentary from Neal Pollack that you cited....

That was my mistake. I'm sorry, I misread your reply - the double negative.

Finally, the consensus statement. Yes, it says "conflicting evidence". That was a charitable acknowledgement of the anecdote you have already mentioned in this thread (your "database"). This is evidence, but it is weak, and it is not comparative evidence where one method has been formally tested against another in some way. There is none of this latter type of evidence in favour of deep stops for decompression diving. In contrast, there are the NEDU and Blatteau studies that are comparative and indicated a possible disadvantage for deep stops. You don't like NEDU. Fine, forget it. There is still Blatteau. But the truth is neither "side" has definitive evidence either way as I have said many times. Thus, there is "conflicting evidence".

More argument left in this yet.

My database was started some time after your 2008 conference. No "charitable acknowledgement" in that.

Reading your UHMS conference report, I see presentations from Doctors and Scientists. I see evidence supporting the positive side too. I have re-read the 10 pages of discussion that lead to this "conflicting evidence" consensus, but I do not see a suggestion of a "charitable acknowledgement" there.

You must remember that this statement was released at a time when deep stops mania was gripping the tech diving world and its purpose was to signal to divers that the matter was not as clear cut are people like you, Ross, would have them believe. And the key point remains the same: you have no basis for claiming superiority for a deep stop approach to decompression.

So the purpose of the consensus statement was social engineer? I hope not. Yes I do have a basis for my claims, but you do want to accept this. You choose to ignore the anecdotal data that is all around us.

I am not the deep-stop antichrist so stop trying to portray me as such. I have modified the deep stop aspects of my diving in the light of available evidence, but I have not abandoned them wholesale. I have been very neutral about the conclusions that can and can't be drawn on this matter. The trouble is, your entrepreneurial implication that deep stops are "more successful" (your words) forces me to take issue with you.

If you were more open to anecdotal data, then your issue with me would be solved, and we could all be happy.

You can't lump all this disagreement onto me. There are entire training organizations, with thousands of very capable an disciplined tech divers. They also include deep stops in a similar fashion to VPM. They also claim a better result. Why are you not actively hounding them?
.

 

[Simon Mitchell]

The passage is spoken by you Simon.

It is difficult to chair a discussion of a statement without reading it out Ross. The fact that the statements were not drafted by me is revealed on page 313.

I didn't say "bubbles don't matter" How dare you! Now you owe me an apology.

I wrote: It might be a small distinction, but its an important one. High bubbles grades are associated with higher decompression STRESS. Not to be confused with (risk of) DCS [opinion Rossh]. You can have high decompression stress, in a stabilized condition, without the occurrence of DCS [opinion Rossh]. For this to progress into DCS, takes some additional conditions (which no one really knows what).

You said that AFTER I challenged you. Your original statement (Post 89) was:

More microbubbles does NOT mean higher risk! Research in this area has failed to find any correlation between microbubble volumes and DCS risk! Despite the obvious desire to link DCS to Spencer count, no researcher has ever been able to connect this.

I think “bubbles don’t matter” is a reasonable summary of your apparent intent here. You actually say it 3 times in the one statement. I do accept that you have modified / clarified this stance. But this is a good example of the sort of incorrect statement you make and get away with in the absence of someone to moderate your commentary.

Yes, the NEDU study (or part of it) was about to be invalidated if it continued.

I cannot get this through to you, but one indisputable fact is that there was a significant difference between the groups before the lower sequential rule would have forced an analysis. The difference demonstrated is therefore perfectly valid.

My database was started some time after your 2008 conference.

Sorry, it was Bruce’s (similar) RGBM database I was referring to.

So the purpose of the consensus statement was social engineer?

Informing divers of the scientific community’s view of the state of the evidence is not social engineering. It is education.

I hope not. Yes I do have a basis for my claims, but you do want to accept this. You choose to ignore the anecdotal data that is all around us.

What your anecdotal data shows is that your decompression methods work most of the time. I have never disputed this. What they don’t show is that these methods are any better (or worse) than anything else.

If you were more open to anecdotal data, then your issue with me would be solved, and we could all be happy.

I am happy with anecdotal data for the purposes described in my above statement, but not as a basis for claims of superiority.

You can't lump all this disagreement onto me. There are entire training organizations, with thousands of very capable an disciplined tech divers. They also include deep stops in a similar fashion to VPM. They also claim a better result. Why are you not actively hounding them?

I have not seen any of them doing it on an internet forum recently.

 

[emmbee]

Noone dives scedules similar or like BVM3 profile.

Just to clarify (I dug up a print of the paper last night while looking for something else), profile A1 is VVAL18 (aka the exponential-linear model), profile A2 is ad-hoc.

BVM3 is a probabilistic bubble volume model that can predict (err, supposedly predict ) the incidence of DCS for a given profile. It estimated the risk of A1 at 6.2% and A2 at 3.7% (I'd imagine that's where the 3%/7% criteria come from). Note that it predicted the deeper profile to be safer.

The idea was to see if that was indeed the case. It was not. Quite the opposite, in fact (regardless of the reject criteria).

So how can someone compare those results to scedules/profiles we dive?

What I make of it:

It does not mean that "deep stops" are Bad. It does not mean that VPM or GFs are crap, never mind that we should all use straight 100/100. It does not mean that people who changed their setup and felt better for it are in fact mistaken and actually feel worse. It does not mean that divers who have profiles they're happy with and that don't get them bent have to go and change things and experiment with their own bodies (more than they already are, anyway ).

It does mean that "deep stops" aren't Good either (they will not necessarily reduce your DCS risk). And it does mean that the general approach that when you get bent the only way forward is to lower your deep GF is incorrect (higher may work, too).

I say "deep stops" because the idea is lacking in the definition department, and I'm thinking that's part of the problem.

Cheers,

Matthieu

 

[gianaameri]

What it means is in the opening part of the study (read the "Abstract"):

http://jap.physiology.org/content/early/2010/09/02/japplphysiol.01369.2009.full.pdf

It is also unmissable from the title of the study:

"High incidence of venous and arterial gas emboli at rest after trimix diving without protocol violations."

That is where the concern is or ought to be (at least that is where my concern is as a diver after seeing the study for the first time, and thanks to Ross for posting the link on CCRX).

What can the experts tell us that we should do to avoid gas bubbles on the arterial side (at least), given the the specific findings of this study?

 

[Igor P]

What it means is in the opening part of the study (read the "Abstract"):

http://jap.physiology.org/content/early/2010/09/02/japplphysiol.01369.2009.full.pdf

It is also unmissable from the title of the study:

"High incidence of venous and arterial gas emboli at rest after trimix diving without protocol violations."

That is where the concern is or ought to be (at least that is where my concern is as a diver after seeing the study for the first time, and thanks to Ross for posting the link on CCRX).

What can the experts tell us that we should do to avoid gas bubbles on the arterial side (at least), given the the specific findings of this study?

My opignion and speculation, the bubbles were of dimensions in which they are stable and not harmful any more. So there is no problem with them. The resurchers that expected no bubbles at all probably did not know how to explain their presence otherways than in a way they did. If the model accounts for those bubbles to be stable and not harmful it will leave you to procede with ascent and if it accounted that when exiting they will be of such dimensions it let divers to ascent to surface and ofgas further there. This is how I see the results of the study.

 

[gianaameri]

My opignion and speculation, the bubbles were of dimensions in which they are stable and not harmful any more. So there is no problem with them. The resurchers that expected no bubbles at all probably did not know how to explain their presence otherways than in a way they did. If the model accounts for those bubbles to be stable and not harmful it will leave you to procede with ascent and if it accounted that when exiting they will be of such dimensions it let divers to ascent to surface and ofgas further there. This is how I see the results of the study.

John Lippmann in his book "Deeper into Diving" says (so I recall, I do not have it handy) that he performed an autopsy on a diver who had performed several deep dives and never reported any problems and he found 40% of the spinal chord damaged.

Is there a hyperbaric specialist doctor prepared to assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers?

 

[Mr fish]

[$QUOTE=gianaameri;134831]John Lippmann in his book "Deeper into Diving" says (so I recall, I do not have it handy) that he performed an autopsy on a diver who had performed several deep dives and never reported any problems and he found 40% of the spinal chord damaged.

Is there a hyperbaric specialist doctor prepared to assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers?[/QUOTE]

Sounds more like Dr Maurice cross

 

[rossh]

I think “bubbles don’t matter” is a reasonable summary of your apparent intent here.

Wrong Simon. You have summarized it poorly. The original statement was brief, but it cannot be condensed into your interpretations. You fail to appreciate the distinctions that I have postulated about DCS and Non DCS conditions that the original statement was referring - also supported in the literature.

Your intentions are becoming too obvious.

I cannot get this through to you, but one indisputable fact is that there was a significant difference between the groups before the lower sequential rule would have forced an analysis. The difference demonstrated is therefore perfectly valid.

Sure, but the test did not go to full length, so it was terminated early - indisputable fact.

The two test profiles were 3.5 hours long, but any normal planning tool has the same dive completed in under 2 hours. The test divers were without any thermal protections, and got very cold after 3.5 hours submerged - indisputable fact.

The test profiles are too long, they don't represent normal use, they do not include any deep stops that represent common use, the test profiles were based on different risk factors so a direct comparison of results is not correct. The results show us more about effects from loss of body heat than deco - opinion.
.

 

[Simon Mitchell]

Wrong Simon. You have summarized it poorly.

I'm happy to let the other readers on here interpret what you said about bubbles (see my immediately previous post).

Your intentions are becoming too obvious.

My intentions are to ensure that the diving community receives objective and accurate information by people who know what they are talking about.

Sure, but the test did not go to full length, so it was terminated early - indisputable fact.

Yes, because the difference between the profiles reached statistical significance and it would have been unethical to continue bending humans to test a question that had already been answered.

Ross, you don't believe there is any value in the NEDU trial at all. Fine. I'm happy to stop talking about it. Even if we pretend it never existed it does not change the fundamental point I have been trying to make all along: there is insufficient comparative evidence to support a claim that one of the debated approaches is better than the other.

Simon M

 

[Mark Chase]

Does either Simon or Ross have any opinion on whether or not adding Helium to the test data will have any impact on the results?

I fully appreciate any answer would be totally theoretical

Id also appreciate any comment on the long held belief that Buhlman overcompensated for the helium. I have for a long time believed that the calculations for the off gassing time of He were overly conservative and that the shallow stops were too long as a result.

Is there any basis for this belief, or its it pure myth.

ATB

Mark

 

[gianaameri]

John Lippmann in his book "Deeper into Diving" says (so I recall, I do not have it handy) that he performed an autopsy on a diver who had performed several deep dives and never reported any problems and he found 40% of the spinal chord damaged.

Is there a hyperbaric specialist doctor prepared to assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers?

Sounds more like Dr Maurice cross

Dr. Maurice Cross of the Diving Diseases Research Centre in Plymouth (or are you making a joke)?

Are you saying he may assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers (or that he "sounds" more like what John Lippmann would say)?

 

[anarchista]

I fully appreciate any answer would be totally theoretical

Lead discussion in most people who are unable to calculate the decompression profile Buhlmann model. It is a simple model does not reflect the body and is quite a good use of statistics.
To pursue such discussions need a doctor who also knows how to do the calculation model, on the other hand technocrat who understands physiology.
Rather than discredit it quickly and knows how to create a mathematical model. Which shows something new.

Now we discuss Simon and Ross speak English but looks completely different, do not come to any specifics.

Who has access to:
Hills B.A., A thermodynamic and kinetic approach to decompression sicknes. Thesis. Libraries Board of South Australia, Adelaide 1966.
Hills B.A., Butler B.D., Size distribution of intravasculat air embolism produced by decompression. Undersea Biomed Res, 1981, 8: 163-170.
Sought information about Jones decompression model 1950, results of Kety 1949, Copperman 1950, Jones 1951, Riggs 1963.

rc greet

 

[gianaameri]

Now we discuss Simon and Ross speak English but looks completely different, do not come to any specifics.

Simply brilliant!

:trophy:

 

[Mark Chase]

Lead discussion in most people who are unable to calculate the decompression profile Buhlmann model. It is a simple model does not reflect the body and is quite a good use of statistics.
To pursue such discussions need a doctor who also knows how to do the calculation model, on the other hand technocrat who understands physiology.
Rather than discredit it quickly and knows how to create a mathematical model. Which shows something new.

Now we discuss Simon and Ross speak English but looks completely different, do not come to any specifics.

Who has access to:
Hills B.A., A thermodynamic and kinetic approach to decompression sicknes. Thesis. Libraries Board of South Australia, Adelaide 1966.
Hills B.A., Butler B.D., Size distribution of intravasculat air embolism produced by decompression. Undersea Biomed Res, 1981, 8: 163-170.
Sought information about Jones decompression model 1950, results of Kety 1949, Copperman 1950, Jones 1951, Riggs 1963.

rc greet

Fine, but bassed on your knowladge do you have an opinion?

I can calculate deco using Buhlman modle its not particularly hard to do but to understand the results? thats something totaly diferent.


I had always beleived that Buhlmans calcualtion for the off gassing of helium was very conservitive. This is a widly held beleife which has been discussed many times in my diving circle.

In the old days of VR3s where we couldent mess with GFs we reduced the HE in the mix to cut back on deco to what was beleived to be more acceptable levels.

So wed dive 16/60 but tell the VR3 we were diving 16/45.

And we didnt get bent.

I do know DrJ Meer was doing this on a massive 180m+ cave dive and got bent, but we considered that dive to be so extreem that any one could have got bent diving just about any profile. depending on what you ate for breakfast.

ATB

Mark

 

[gianaameri]

John Lippmann in his book "Deeper into Diving" says (so I recall, I do not have it handy) that he performed an autopsy on a diver who had performed several deep dives and never reported any problems and he found 40% of the spinal chord damaged.

Is there a hyperbaric specialist doctor prepared to assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers?

Sounds more like Dr Maurice cross

Dr. Maurice Cross of the Diving Diseases Research Centre in Plymouth (or are you making a joke)?

Are you saying he may assert that profiles producing ARTERIAL bubbles should be acceptable in recreational divers (or that he "sounds" more like what John Lippmann would say)?

All I could find linked to Dr. Maurice Cross is that he (or the studies he refers to) would associate arterial bubbles with spinal and cutaneous injury (and not regard arterial bubbles as insignificant):

See: http://www.ddrc.info/research/docs/wilmshurst_2000.pdf

and also see: http://www.ddrc.info/research/docs/wilmshurst_cutaneous_2001.pdf

The above is my personal understanding of objective data/information sourced from medical archives.

 

[anarchista]

I can calculate deco using Buhlman modle its not particularly hard to do but to understand the results? thats something totaly diferent.


I had always beleived that Buhlmans calcualtion for the off gassing of helium was very conservitive. This is a widly held beleife which has been discussed many times in my diving circle.

Check decompression heilox the U.S. Navy manual, yes it after riding a border but see profile (here we have a table in the pressure of the helium must be added to the oxygen pressure, to determine the depth, in the form of a table is more versatile).

http://rebreathers.pl/forum/download.php?id=43

rc greet

 

[gianaameri]

Comparison of saturation decompression model with other models is a strong argument to scale.
This type of decompression is actually one tissue model. Longest tissue controls virtually all poces decompression. All they manage to degas faster, with little saturation.

Empirical model of the U.S. Navy (Direction of Comander, Naval Sea Systems Command, 2008) is a surprisingly good correlation with the model Hempelman.
Hempelman model is a model of one tissue. In its structure there are no places where there may be problems with the formation of bubbles.

Heliox decompression of high ppO2 is already full field of problems, as well as TMX or Nitrox decompression. A wide range of tissues involved in decompression, it is necessary to remove the inert gas is released.

Comparisons of the problem, to the models one tissue, are not an argument.

greet rc

??? This one tissue model you refer to:

http://www.phr.net.pl/material/2011r/PHR2(35)2011/7_r.klos_PHR2(35)2011.pdf

 

[anarchista]

but RC has some substance, plus Poland is a repository of "know-how"

You wrote the post, usually I roasted on a spit author.
It just so happens that I have a lot of literature in this area, for the construction of research testing of prototypes. That's why I have so much information advantage. also find the list of copies of copyright in Ryszard Klos.
Additionally, as you know I am an active inventor, you know only a small part of what I do.

??? This one tissue model you refer to:

http://www.phr.net.pl/material/2011r/PHR2(35)2011/7_r.klos_PHR2(35)2011.pdf

Yes Hempelnan model is one example of one tissue with a finite capacity for dissolved inert gas.

But the model is to decompress one tissue saturated, the book "Opportunities Selection Decompression for Apparatus Diving type CRABE" Ryszard Klos 2011, comes this piece, that you found. There is a decompression Heliox. "The rate of decompression can be determined from equation (3.2), which was replaced by inert gas partial pressure Pi of the initial value of the tension in the tissue of theoretical Pio, which for diving saturowanych is fully justified (AR Behnke. 1975)
.....
Behnke postulate was based on the observation that the saturation decompression mechanism is different than the short-term dives and decompression is the preferred way of its continuous form, as opposed to short-term dives 88, continuous decompression rate can be so calculated by differentiating the model (3.19):
dP / dt = k (Pio) exp-kt "

With such a slow ascent all the bubbles arising in other tissues faster have plenty of time to disappear.

I wonder why I write. finally the basics, that every diver speaking English, knows. (joke)

greet rc

 

[rossh]

Does either Simon or Ross have any opinion on whether or not adding Helium to the test data will have any impact on the results?

I fully appreciate any answer would be totally theoretical

Id also appreciate any comment on the long held belief that Buhlman overcompensated for the helium. I have for a long time believed that the calculations for the off gassing time of He were overly conservative and that the shallow stops were too long as a result.

Is there any basis for this belief, or its it pure myth.

ATB

Mark

Hi Mark,

My opinion - its hard to tell which way a similar test might go. The bulk of the dive profile consists of cold divers in a shallow profile, doing far too much time in the water. 174 min ascent for a 30 min bottom (6:1). Would you want to repeat that profile, or use a deco time that was realistic. If total time was lowered, then the cold diver factor would be less.

I guess it depends on what is used for deco mix. Is it back gas helium or shift to EAN? If they ran helium all the way, then it might give less issues, but stronger VGE. What mix helium would you choose for a proper 1 to 1 comparison?

If they used EAN for deco, or particularly air deco, they might be back with the same issue, or IBCD issues too. There is a great deal of on gassing in the almost 3 hours needed to ascend that profile.

There is no easy answer to this one.


On the Buhlmann helium question. On one hand we have the suggestions you made, that the last portions were overly conservative. Then we have the every day implementation of his model. The trend is for divers adding extra to his times with GF x/70. That loosely translates to a 30% safety factor added.

Less or more or just right?

 

[gianaameri]

I am confused so maybe others are confused. I think that maybe there is more than one study being discussed and there is some flipping back and forth in the thread (reason of my confusion).

The study which gives rise to concerns (arterial bubbles using VPM model) and which I cross-checked on CDM-18 (representing man-tested models Buhlmann, COMEX, DCAP, USM-Workman) is this one:

http://jap.physiology.org/content/early/2010/09/02/japplphysiol.01369.2009.full.pdf

and the 3 dive schedules I was given for the above linked study are these ones (none are long dives, divers not cold either, only 1 of 7 divers with PFO):

Decompression model: VPM - B

DIVE PLAN #1
Surface interval = 1 day 0 hr 0 min.
Elevation = 0m
Conservatism = Nominal

Dec to 60m (4) Trimix 16/45 15m/min descent.
Dec to 63m (4) Trimix 16/45 18m/min descent.
Level 63m 15:50 (20) Trimix 16/45 1.16 ppO2, 26m ead,
30m end
Asc to 39m (22) Trimix 16/45 -9m/min ascent.
Stop at 39m 0:20 (23) Trimix 16/45 0.78 ppO2, 14m
ead, 17m end
Stop at 36m 1:00 (24) Trimix 16/45 0.73 ppO2, 13m
ead, 15m end
Stop at 33m 1:00 (25) Trimix 16/45 0.68 ppO2, 11m
ead, 14m end
Stop at 30m 1:00 (26) Trimix 16/45 0.64 ppO2, 10m
ead, 12m end
Stop at 27m 2:00 (28) Trimix 16/45 0.59 ppO2, 8m
ead, 10m end
Stop at 24m 2:00 (30) Trimix 16/45 0.54 ppO2, 7m
ead, 9m end
Stop at 21m 2:00 (32) Nitrox 50 1.54 ppO2, 10m ead
Stop at 18m 2:00 (34) Nitrox 50 1.39 ppO2, 8m ead
Stop at 15m 2:00 (36) Nitrox 50 1.24 ppO2, 6m ead
Stop at 12m 3:00 (39) Nitrox 50 1.10 ppO2, 4m ead
Stop at 9m 5:00 (44) Nitrox 50 0.95 ppO2, 2m ead
Stop at 6m 22:00 (66) Nitrox 50 0.80 ppO2, 0m ead
Surface (66) Nitrox 50 -9m/min ascent.

Off gassing starts at 48.6m

OTU's this dive: 59
CNS Total: 21.7%

121.7 cu ft Trimix 16/45
40.8 cu ft Nitrox 50
162.5 cu ft TOTAL


DIVE PLAN #2
Surface interval = 1 day 0 hr 0 min.
Elevation = 0m
Conservatism = Nominal

Dec to 60m (4) Trimix 17/47 15m/min descent.
Dec to 66m (4) Trimix 17/47 18m/min descent.
Level 66m 15:40 (20) Trimix 17/47 1.28 ppO2, 25m ead,
30m end
Asc to 42m (22) Trimix 17/47 -9m/min ascent.
Stop at 42m 0:20 (23) Trimix 17/47 0.88 ppO2, 14m
ead, 18m end
Stop at 39m 1:00 (24) Trimix 17/47 0.83 ppO2, 12m
ead, 16m end
Stop at 36m 1:00 (25) Trimix 17/47 0.78 ppO2, 11m
ead, 14m end
Stop at 33m 1:00 (26) Trimix 17/47 0.73 ppO2, 10m
ead, 13m end
Stop at 30m 1:00 (27) Trimix 17/47 0.68 ppO2, 8m
ead, 11m end
Stop at 27m 2:00 (29) Trimix 17/47 0.63 ppO2, 7m
ead, 10m end
Stop at 24m 2:00 (31) Trimix 17/47 0.57 ppO2, 5m
ead, 8m end
Stop at 21m 2:00 (33) Nitrox 50 1.54 ppO2, 10m ead
Stop at 18m 2:00 (35) Nitrox 50 1.39 ppO2, 8m ead
Stop at 15m 2:00 (37) Nitrox 50 1.24 ppO2, 6m ead
Stop at 12m 4:00 (41) Nitrox 50 1.10 ppO2, 4m ead
Stop at 9m 5:00 (46) Nitrox 50 0.95 ppO2, 2m ead
Stop at 6m 23:00 (69) Nitrox 50 0.80 ppO2, 0m ead
Surface (69) Nitrox 50 -9m/min ascent.

Off gassing starts at 49.9m

OTU's this dive: 66
CNS Total: 24.4%

128.6 cu ft Trimix 17/47
43.0 cu ft Nitrox 50
171.6 cu ft TOTAL


DIVE PLAN #3
Surface interval = 1 day 0 hr 0 min.
Elevation = 0m
Conservatism = Nominal

Dec to 60m (4) Trimix 17/49 15m/min descent.
Dec to 64m (4) Trimix 17/49 18m/min descent.
Level 64m 14:47 (19) Trimix 17/49 1.25 ppO2, 22m ead,
28m end
Asc to 39m (21) Trimix 17/49 -9m/min ascent.
Stop at 39m 0:13 (22) Trimix 17/49 0.83 ppO2, 11m
ead, 15m end
Stop at 36m 1:00 (23) Trimix 17/49 0.78 ppO2, 10m
ead, 13m end
Stop at 33m 1:00 (24) Trimix 17/49 0.73 ppO2, 8m
ead, 12m end
Stop at 30m 1:00 (25) Trimix 17/49 0.68 ppO2, 7m
ead, 10m end
Stop at 27m 2:00 (27) Trimix 17/49 0.63 ppO2, 6m
ead, 9m end
Stop at 24m 2:00 (29) Trimix 17/49 0.57 ppO2, 5m
ead, 7m end
Stop at 21m 2:00 (31) Nitrox 50 1.54 ppO2, 10m ead
Stop at 18m 1:00 (32) Nitrox 50 1.39 ppO2, 8m ead
Stop at 15m 2:00 (34) Nitrox 50 1.24 ppO2, 6m ead
Stop at 12m 4:00 (38) Nitrox 50 1.10 ppO2, 4m ead
Stop at 9m 4:00 (42) Nitrox 50 0.95 ppO2, 2m ead
Stop at 6m 21:00 (63) Nitrox 50 0.80 ppO2, 0m ead
Surface (63) Nitrox 50 -9m/min ascent.

Off gassing starts at 48.3m

OTU's this dive: 59
CNS Total: 21.8%

117.9 cu ft Trimix 17/49
38.3 cu ft Nitrox 50
156.2 cu ft TOTAL


DIVE PLAN COMPLETE