OC has less deco than CCR below 200'?

[Grateful Diver]

can i play?
i spent the last few years being the oc token
with many ccr partners on some pretty nice dives
nothing legendary

but the admiral sampson was pretty cool

not once, EVER (as in never) did the ccr buddies clear before me
oddly, not once, EVER (as in never) did i (on oc) clear before my team
all in together
all out together
every time

maybe my numbers were a few shorter
maybe the ccr dude was a few shorter
but if your deco comes down to a 4 minute difference
and you actually believe it makes a difference
i got this bridge i have been trying to sell.......

Thank you ...

I know that on the dive we did on Monday, three of us got in the water together and three of us got out together. Two were on OC and one on CCR. Didn't seem to make a whole lot of difference.

Then again, we only went to 207 ... wussie dive.

... Bob (Grateful Diver)

[mz53480]

....And anyone who feels like puking in the chamber has my permission to do so, whether or not it' an officially recognized "symptom" of DCS, CNS toxicity, or chlamydia.

[LCF]

Thanks for the info -- You can sure tell I don't know much about CCRs! I didn't realize you couldn't push the ppO2s up in the shallows. Learn something every day.

[loanwolf]

Greg: Look, man- you're in a class by yourself. You recently declared, on this site, that dives above 300 fsw "weren't really tech dives."

You also shared with us, on this site, that you spent ~650 hrs underwater last year.

ON TOP OF WHICH, you shared with us the fact that you were working with DARPA, and did 600 and 800' dives with them.


WOW.


Look, seriously- the rest of us cannot begin to compete with that kind of stuff. Who knew, when you were still diving OC, when you were DMing my CCR trimix class, that you would get a revo, a year later, and push the limits of diving so far, in such a short time? I, for one, am very impressed.

But- please don't try and raise the bar. Newbies are still newbies: and I would really hate to see anyone hurt trying to follow your example. The vast majority of human beings are not capable of doing even half of what you can do- summitting Everest without 02? Scootering from cove 1 to the fishing reef and back without surfacing? Amazing accomplishments, to be sure. But maybe, just maybe, you could be encouraging one of us "mere mortals" to push things too far.

Josh you have lost me I do not see were I am talking about pushing things here. These are two dive profiles for a 200' dive witch is what this thread is all about. A CCR diver is going to get out of the water faster than OC almost 99% of the time. The only time that is not going to happen is when you do say 10 min at 200' as we saturate He faster. But the longer you stay the more that get pronounced. I am not trashing on anyone or anything like that. As I was reading this thread I was reading it as OC is going to get out faster and that is not true. So that is why I responded on it and posted up actual numbers head to head on the 200' dive that was being asked about. If you run the numbers, CCR is going to get out much faster than OC is going to. Now run the numbers with a 30min@200' dive and see what you get, it is about a 17 min difference. On the last dive of the day the CCR divers are usually on our second beer by the time the OC guys get out of the water.

I am not trying to raise the bar and you confuse me their. You were taught in your class to do a O2 flush it is a safety thing to check the cells, yes you do wast O2 but it is cheap who cares. And you are emptying the loop so you can offgass He faster as well that is a side benefit. It will not get you out of the water much faster unless you are really diving a long dive and have saturated with He. You were also taught to crank up your PO2 when doing deco is okay. Josh you and I have a benefit as we are also getting a live reading on our CNS levels it is on your integrated computer so you can fly your CNS as well, if your CNS is only at 35%, hell run your PO2 up and get out of the water a few minutes faster. On even long 130' or less multi day dives the CNS number can be the number you may have to use and not your deco on when to turn a dive on CCR.

As I said I am confused.

[rjw]

[BDub]

As I said I am confused.

I won't speak for Josh, and I'm never one to tell others how to dive, but this is what I find disturbing:

Dec to 200ft (3) Trimix 17/35 60ft/min descent.
Level 200ft 16:40 (20) Trimix 17/35 1.20 ppO2, 109ft ead, 118ft end
Asc to 120ft (22) Trimix 17/35 -30ft/min ascent.
Stop at 120ft 0:20 (23) Trimix 17/35 0.79 ppO2, 60ft ead, 66ft end
Stop at 110ft 1:00 (24) Trimix 17/35 0.74 ppO2, 54ft ead, 60ft end
Stop at 100ft 1:00 (25) Trimix 17/35 0.68 ppO2, 48ft ead, 53ft end
Stop at 90ft 1:00 (26) Trimix 17/35 0.63 ppO2, 42ft ead, 47ft end
Stop at 80ft 2:00 (28) Trimix 17/35 0.58 ppO2, 36ft ead, 40ft end
Stop at 70ft 2:00 (30) Nitrox 50 1.56 ppO2, 32ft ead
Stop at 60ft 1:00 (31) Nitrox 50 1.41 ppO2, 26ft ead
Stop at 50ft 2:00 (33) Nitrox 50 1.26 ppO2, 20ft ead
Stop at 40ft 3:00 (36) Nitrox 50 1.10 ppO2, 13ft ead
Stop at 30ft 4:00 (40) Nitrox 50 0.95 ppO2, 7ft ead
Stop at 20ft 14:00 (54) Oxygen 1.60 ppO2, 0ft ead
Surface (54) Oxygen -30ft/min ascent.

Off gassing starts at 151.2ft

OTU's this dive: 72
CNS Total: 47.5%

117.7 cu ft Trimix 17/35
19.7 cu ft Nitrox 50
16.0 cu ft Oxygen
153.4 cu ft TOTAL

Some people read this stuff to learn.

I'll be the first to admit that I haven't done the dives you have, but I've also done enough to know how I'd feel after looking at a particular profile and I can say that I'd feel pretty damn sore after being knotted up in a pretzel like that. That would bend the crap out of me, and I tend to deco pretty efficiently.

In short, on a 200' dive for :20, you're advocating only :24 of deco, with abbreviated deep stops as well.

To put things in perspective, for that profile, from 150' (my first stop) to the surface using 18/45, EAN50 and O2, my ascent would take ~:51. Yours is :32. HUGE difference, even with the difference in bottom gas.

I firmly believe that deco isn't an exact science, by any stretch, and a few minutes here or there isn't a big deal in the grand scheme. I also think people should dive the profiles that work for them, and this may work for you, but this kind of profile could get someone in a lot of trouble, OC or CCR.

[CaptnJack]

Despite my suggestion earlier, its probably best not to use v-planner profiles as "evidence". You can put in just about anything to "prove a point" but its apples & oranges in the end.

[loanwolf]

Some people read this stuff to learn.

I'll be the first to admit that I haven't done the dives you have, but I've also done enough to know how I'd feel after looking at a particular profile and I can say that I'd feel pretty damn sore after being knotted up in a pretzel like that. That would bend the crap out of me, and I tend to deco pretty efficiently.

In short, on a 200' dive for :20, you're advocating only :24 of deco, with abbreviated deep stops as well.

To put things in perspective, for that profile, from 150' (my first stop) to the surface using 18/45, EAN50 and O2, my ascent would take ~:51. Yours is :32. HUGE difference.

I firmly believe that deco isn't an exact science, by any stretch, and a few minutes here or there isn't a big deal in the grand scheme. I also think people should dive the profiles that work for them, and this may work for you, but this kind of profile could get someone in a lot of trouble, OC or CCR.

I agree with you everyone is going to be different so you have to cut your own tables. This is a standard V-Planner profile. It depends on what your conservatism is set at and personal variables. for the comparison I put it at nominal as this was a comparison of two different profiles talking about getting out of the water the fastest.

I use nominal when I cut my tables for any dive anyways, as they are for emergency use to get me out of the water safely as fast as possible as I have lost both my primary and backup computers that are being flown live. I do the same thing on OC the cut tables are only for emergency use. I fly the live computers which are adjusting my deco as the dive is going along. If i am a good dive I get credited with less deco if I am a bad diver or working too had I get penalized with more deco.

Running live computers on your dive you will probably be out of the water before even this table. As you will probably not be doing a square profile. So your computers are going to credit you for the shallower time and the cut table is out out of prospective now buy maybe up to a few minutes or more depending on your profile. At that point you are getting into semantics over conservatism factors that I was trying to stay away from on this thread as that is a whole different can of worms.

[loanwolf]

Despite my suggestion earlier, its probably best not to use v-planner profiles as "evidence". You can put in just about anything to "prove a point" but its apples & oranges in the end.

I do not get your statement here as they are not apples to oranges. these were nominal profiles as baseline as can be done no changes for conservatism or personal variables (nominal). Their is no number tweaking going on their it is baseline.

[Sounder]

...and anyone who feels like puking in the chamber has my permission to do so, whether or not it' an officially recognized "symptom" of DCS, CNS toxicity, or chlamydia.

I'm not sure whatch'all are talkin' bout, but I done got myself a new siggie!

[CaptnJack]

Despite my suggestion earlier, its probably best not to use v-planner profiles as "evidence". You can put in just about anything to "prove a point" but its apples & oranges in the end.

I do not get your statement here as they are not apples to oranges. these were nominal profiles as baseline as can be done no changes for conservatism or personal variables (nominal). Their is no number tweaking going on their it is baseline.

As long as you are running the same conservatism setting for both CCR and OC, nominal has no bearing on "faster". Conservatism setting is independent of breathing mode. However OC (or bailout) mix choices do have a significant influence, as well as BT, what setpoint you allow the CCR diver to run, and to what extent you allow someone to violate CNS limits. All things better learned in a class than playing with vplanner profiles.

[Joshua Smith]

Like I said earlier in this thread- OC's advantage over CCR becomes apparent on dives deeper than 200'. Here's vplanner on a 300' dive. I probably used the wrong deco gasses, but I'm probably not too far off, either:


Dec to 200ft (4) Trimix 10/70 50ft/min descent.
Dec to 300ft (5) Trimix 10/70 60ft/min descent.
Level 300ft 14:20 (20) Trimix 10/70 1.01 ppO2, 51ft ead, 67ft end
Asc to 230ft (22) Trimix 10/70 -30ft/min ascent.
Stop at 230ft 0:40 (23) Trimix 10/70 0.80 ppO2, 34ft ead, 46ft end
Stop at 220ft 1:00 (24) Trimix 10/70 0.77 ppO2, 31ft ead, 43ft end
Stop at 210ft 1:00 (25) Trimix 10/70 0.74 ppO2, 28ft ead, 40ft end
Stop at 200ft 1:00 (26) Trimix 10/70 0.70 ppO2, 26ft ead, 37ft end
Stop at 190ft 1:00 (27) Trimix 20/25 1.35 ppO2, 122ft ead, 134ft end
Stop at 180ft 1:00 (28) Trimix 20/25 1.29 ppO2, 115ft ead, 127ft end
Stop at 170ft 1:00 (29) Trimix 20/25 1.23 ppO2, 108ft ead, 119ft end
Stop at 160ft 1:00 (30) Trimix 20/25 1.17 ppO2, 101ft ead, 112ft end
Stop at 150ft 1:00 (31) Trimix 20/25 1.11 ppO2, 94ft ead, 104ft end
Stop at 140ft 1:00 (32) Trimix 20/25 1.05 ppO2, 87ft ead, 97ft end
Stop at 130ft 1:00 (33) Trimix 20/25 0.99 ppO2, 80ft ead, 89ft end
Stop at 120ft 1:00 (34) Trimix 20/25 0.93 ppO2, 73ft ead, 82ft end
Stop at 110ft 2:00 (36) Trimix 20/25 0.87 ppO2, 67ft ead, 74ft end
Stop at 100ft 3:00 (39) Trimix 20/25 0.80 ppO2, 60ft ead, 67ft end
Stop at 90ft 2:00 (41) Nitrox 40 1.49 ppO2, 60ft ead
Stop at 80ft 3:00 (44) Nitrox 40 1.37 ppO2, 53ft ead
Stop at 70ft 3:00 (47) Nitrox 40 1.25 ppO2, 45ft ead
Stop at 60ft 4:00 (51) Nitrox 40 1.13 ppO2, 38ft ead
Stop at 50ft 6:00 (57) Nitrox 40 1.00 ppO2, 30ft ead
Stop at 40ft 7:00 (64) Nitrox 40 0.88 ppO2, 22ft ead
Stop at 30ft 11:00 (75) Nitrox 40 0.76 ppO2, 15ft ead
Stop at 20ft 35:00 (110) Oxygen 1.60 ppO2, 0ft ead
Surface (110) Oxygen -30ft/min ascent.


As you can see, it's giving 110 minutes run time.

Here's the same dive on CCR:

Dec to 200ft (4) Diluent 10/70
Dec to 300ft (5) Diluent 10/70
Level 300ft 14:20 (20) Diluent 10/70
Asc to 230ft (22) Diluent 10/70
Stop at 230ft 0:40 (23) Diluent 10/70
Stop at 220ft 1:00 (24) Diluent 10/70
Stop at 210ft 1:00 (25) Diluent 10/70
Stop at 200ft 1:00 (26) Diluent 10/70
Stop at 190ft 1:00 (27) Diluent 10/70
Stop at 180ft 1:00 (28) Diluent 10/70
Stop at 170ft 1:00 (29) Diluent 10/70
Stop at 160ft 1:00 (30) Diluent 10/70
Stop at 150ft 1:00 (31) Diluent 10/70
Stop at 140ft 1:00 (32) Diluent 10/70
Stop at 130ft 2:00 (34) Diluent 10/70
Stop at 120ft 2:00 (36) Diluent 10/70
Stop at 110ft 2:00 (38) Diluent 10/70
Stop at 100ft 3:00 (41) Diluent 10/70
Stop at 90ft 3:00 (44) Diluent 10/70
Stop at 80ft 4:00 (48) Diluent 10/70
Stop at 70ft 4:00 (52) Diluent 10/70
Stop at 60ft 6:00 (58) Diluent 10/70
Stop at 50ft 6:00 (64) Diluent 10/70
Stop at 40ft 8:00 (72) Diluent 10/70
Stop at 30ft 11:00 (83) Diluent 10/70
Stop at 20ft 42:00 (125) Diluent 10/70
Surface (125) Diluent 10/70

125 minutes > 100 minutes.

[loanwolf]

Despite my suggestion earlier, its probably best not to use v-planner profiles as "evidence". You can put in just about anything to "prove a point" but its apples & oranges in the end.

I do not get your statement here as they are not apples to oranges. these were nominal profiles as baseline as can be done no changes for conservatism or personal variables (nominal). Their is no number tweaking going on their it is baseline.

As long as you are running the same conservatism setting for both CCR and OC, nominal has no bearing on "faster". Conservatism setting is independent of breathing mode. However OC (or bailout) mix choices do have a significant influence, as well as BT, what setpoint you allow the CCR diver to run, and to what extent you allow someone to violate CNS limits. All things better learned in a class than playing with vplanner profiles.

I agree with you, you can tweak things to do what ever you want to do with software. That is why i used nominal and put in standard gasses.

Their has been nothing here that violates standards everything I have talked about is well above the board. I did not come in with commercial standards or even mention anything that is non recreational. I put in standard mixes for both types. thanks for pointing out that the 20/40 was selected I missed that one, 20/40 is a standard BO gas I use but it did not change the time at all when it was thier.

CCR enables you to stay longer with less deco than OC. If you are running side by side with OC you are not really taking advantage of the CCR. You are diving as a group and you should all clear at about the same time depending on individual conservatisms. It is when you start pushing past the 20min bottom time that is when the CCR really starts to preform. And then again you are not even getting anywhere near your CNS limits. Not until you start to push out to hrs of bottom time or doing 3 or 4 200' dives a day over multiple days that CNS becomes a problem.

[Joshua Smith]

Take another look at my post above. Also, both of those profiles are approaching 100% of the CNS clock, by the way.

[loanwolf]

Like I said earlier in this thread- OC's advantage over CCR becomes apparent on dives deeper than 200'. Here's vplanner on a 300' dive. I probably used the wrong deco gasses, but I'm probably not too far off, either:


Dec to 200ft (4) Trimix 10/70 50ft/min descent.
Dec to 300ft (5) Trimix 10/70 60ft/min descent.
Level 300ft 14:20 (20) Trimix 10/70 1.01 ppO2, 51ft ead, 67ft end
Asc to 230ft (22) Trimix 10/70 -30ft/min ascent.
Stop at 230ft 0:40 (23) Trimix 10/70 0.80 ppO2, 34ft ead, 46ft end
Stop at 220ft 1:00 (24) Trimix 10/70 0.77 ppO2, 31ft ead, 43ft end
Stop at 210ft 1:00 (25) Trimix 10/70 0.74 ppO2, 28ft ead, 40ft end
Stop at 200ft 1:00 (26) Trimix 10/70 0.70 ppO2, 26ft ead, 37ft end
Stop at 190ft 1:00 (27) Trimix 20/25 1.35 ppO2, 122ft ead, 134ft end
Stop at 180ft 1:00 (28) Trimix 20/25 1.29 ppO2, 115ft ead, 127ft end
Stop at 170ft 1:00 (29) Trimix 20/25 1.23 ppO2, 108ft ead, 119ft end
Stop at 160ft 1:00 (30) Trimix 20/25 1.17 ppO2, 101ft ead, 112ft end
Stop at 150ft 1:00 (31) Trimix 20/25 1.11 ppO2, 94ft ead, 104ft end
Stop at 140ft 1:00 (32) Trimix 20/25 1.05 ppO2, 87ft ead, 97ft end
Stop at 130ft 1:00 (33) Trimix 20/25 0.99 ppO2, 80ft ead, 89ft end
Stop at 120ft 1:00 (34) Trimix 20/25 0.93 ppO2, 73ft ead, 82ft end
Stop at 110ft 2:00 (36) Trimix 20/25 0.87 ppO2, 67ft ead, 74ft end
Stop at 100ft 3:00 (39) Trimix 20/25 0.80 ppO2, 60ft ead, 67ft end
Stop at 90ft 2:00 (41) Nitrox 40 1.49 ppO2, 60ft ead
Stop at 80ft 3:00 (44) Nitrox 40 1.37 ppO2, 53ft ead
Stop at 70ft 3:00 (47) Nitrox 40 1.25 ppO2, 45ft ead
Stop at 60ft 4:00 (51) Nitrox 40 1.13 ppO2, 38ft ead
Stop at 50ft 6:00 (57) Nitrox 40 1.00 ppO2, 30ft ead
Stop at 40ft 7:00 (64) Nitrox 40 0.88 ppO2, 22ft ead
Stop at 30ft 11:00 (75) Nitrox 40 0.76 ppO2, 15ft ead
Stop at 20ft 35:00 (110) Oxygen 1.60 ppO2, 0ft ead
Surface (110) Oxygen -30ft/min ascent.


As you can see, it's giving 110 minutes run time.

Here's the same dive on CCR:

Dec to 200ft (4) Diluent 10/70
Dec to 300ft (5) Diluent 10/70
Level 300ft 14:20 (20) Diluent 10/70
Asc to 230ft (22) Diluent 10/70
Stop at 230ft 0:40 (23) Diluent 10/70
Stop at 220ft 1:00 (24) Diluent 10/70
Stop at 210ft 1:00 (25) Diluent 10/70
Stop at 200ft 1:00 (26) Diluent 10/70
Stop at 190ft 1:00 (27) Diluent 10/70
Stop at 180ft 1:00 (28) Diluent 10/70
Stop at 170ft 1:00 (29) Diluent 10/70
Stop at 160ft 1:00 (30) Diluent 10/70
Stop at 150ft 1:00 (31) Diluent 10/70
Stop at 140ft 1:00 (32) Diluent 10/70
Stop at 130ft 2:00 (34) Diluent 10/70
Stop at 120ft 2:00 (36) Diluent 10/70
Stop at 110ft 2:00 (38) Diluent 10/70
Stop at 100ft 3:00 (41) Diluent 10/70
Stop at 90ft 3:00 (44) Diluent 10/70
Stop at 80ft 4:00 (48) Diluent 10/70
Stop at 70ft 4:00 (52) Diluent 10/70
Stop at 60ft 6:00 (58) Diluent 10/70
Stop at 50ft 6:00 (64) Diluent 10/70
Stop at 40ft 8:00 (72) Diluent 10/70
Stop at 30ft 11:00 (83) Diluent 10/70
Stop at 20ft 42:00 (125) Diluent 10/70
Surface (125) Diluent 10/70

125 minutes > 100 minutes.

Josh what is your setpoint? something does not look right if you are getting that. are booth on nominal?

I would run 10/50 for this as you END would be 140' on that dive. I get this with nominal numbers for CCR.

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

Dec to 200ft (3) Diluent 10/50 0.70 SetPoint, 60ft/min descent.
Dec to 300ft (4) Diluent 10/50 0.70 SetPoint, 80ft/min descent.
Level 300ft 15:25 (20) Diluent 10/50 1.30 SetPoint, 130ft ead, 139ft end
Asc to 220ft (22) Diluent 10/50 1.50 SetPoint, -30ft/min ascent.
Stop at 220ft 0:20 (23) Diluent 10/50 1.50 SetPoint, 82ft ead, 107ft end
Stop at 210ft 1:00 (24) Diluent 10/50 1.50 SetPoint, 76ft ead, 102ft end
Stop at 200ft 1:00 (25) Diluent 10/50 1.50 SetPoint, 71ft ead, 98ft end
Stop at 190ft 1:00 (26) Diluent 10/50 1.50 SetPoint, 65ft ead, 93ft end
Stop at 180ft 1:00 (27) Diluent 10/50 1.50 SetPoint, 59ft ead, 89ft end
Stop at 170ft 1:00 (28) Diluent 10/50 1.50 SetPoint, 54ft ead, 84ft end
Stop at 160ft 1:00 (29) Diluent 10/50 1.50 SetPoint, 48ft ead, 80ft end
Stop at 150ft 1:00 (30) Diluent 10/50 1.50 SetPoint, 42ft ead, 75ft end
Stop at 140ft 1:00 (31) Diluent 10/50 1.50 SetPoint, 37ft ead, 71ft end
Stop at 130ft 1:00 (32) Diluent 10/50 1.50 SetPoint, 31ft ead, 67ft end
Stop at 120ft 1:00 (33) Diluent 10/50 1.50 SetPoint, 26ft ead, 62ft end
Stop at 110ft 2:00 (35) Diluent 10/50 1.50 SetPoint, 20ft ead, 58ft end
Stop at 100ft 2:00 (37) Diluent 10/50 1.50 SetPoint, 14ft ead, 53ft end
Stop at 90ft 2:00 (39) Diluent 10/50 1.50 SetPoint, 9ft ead, 49ft end
Stop at 80ft 3:00 (42) Diluent 10/50 1.50 SetPoint, 3ft ead, 44ft end
Stop at 70ft 3:00 (45) Diluent 10/50 1.50 SetPoint, 0ft ead, 40ft end
Stop at 60ft 4:00 (49) Diluent 10/50 1.50 SetPoint, 0ft ead, 35ft end
Stop at 50ft 4:00 (53) Diluent 10/50 1.50 SetPoint, 0ft ead, 31ft end
Stop at 40ft 6:00 (59) Diluent 10/50 1.50 SetPoint, 0ft ead, 27ft end
Stop at 30ft 7:00 (66) Diluent 10/50 1.50 SetPoint, 0ft ead, 22ft end
Stop at 20ft 28:00 (94) Diluent 10/50 1.50 SetPoint, 0ft ead, 18ft end
Surface (94) Diluent 10/50 -30ft/min ascent.

Off gassing starts at 235.5ft

OTU's this dive: 158
CNS Total: 71.3%

----------------------

10/70 will give you about 103 min of run time at a 1.3 and a 1.5 for deco.

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

Dec to 200ft (3) Diluent 10/70 0.70 SetPoint, 60ft/min descent.
Dec to 300ft (4) Diluent 10/70 0.70 SetPoint, 80ft/min descent.
Level 300ft 15:25 (20) Diluent 10/70 1.30 SetPoint, 49ft ead, 74ft end
Asc to 220ft (22) Diluent 10/70 1.50 SetPoint, -30ft/min ascent.
Stop at 220ft 0:20 (23) Diluent 10/70 1.50 SetPoint, 24ft ead, 61ft end
Stop at 210ft 1:00 (24) Diluent 10/70 1.50 SetPoint, 22ft ead, 59ft end
Stop at 200ft 1:00 (25) Diluent 10/70 1.50 SetPoint, 19ft ead, 57ft end
Stop at 190ft 1:00 (26) Diluent 10/70 1.50 SetPoint, 16ft ead, 55ft end
Stop at 180ft 1:00 (27) Diluent 10/70 1.50 SetPoint, 13ft ead, 52ft end
Stop at 170ft 1:00 (28) Diluent 10/70 1.50 SetPoint, 10ft ead, 50ft end
Stop at 160ft 1:00 (29) Diluent 10/70 1.50 SetPoint, 7ft ead, 48ft end
Stop at 150ft 1:00 (30) Diluent 10/70 1.50 SetPoint, 5ft ead, 46ft end
Stop at 140ft 1:00 (31) Diluent 10/70 1.50 SetPoint, 2ft ead, 43ft end
Stop at 130ft 1:00 (32) Diluent 10/70 1.50 SetPoint, 0ft ead, 41ft end
Stop at 120ft 2:00 (34) Diluent 10/70 1.50 SetPoint, 0ft ead, 39ft end
Stop at 110ft 2:00 (36) Diluent 10/70 1.50 SetPoint, 0ft ead, 37ft end
Stop at 100ft 2:00 (38) Diluent 10/70 1.50 SetPoint, 0ft ead, 35ft end
Stop at 90ft 3:00 (41) Diluent 10/70 1.50 SetPoint, 0ft ead, 32ft end
Stop at 80ft 3:00 (44) Diluent 10/70 1.50 SetPoint, 0ft ead, 30ft end
Stop at 70ft 3:00 (47) Diluent 10/70 1.50 SetPoint, 0ft ead, 28ft end
Stop at 60ft 4:00 (51) Diluent 10/70 1.50 SetPoint, 0ft ead, 26ft end
Stop at 50ft 6:00 (57) Diluent 10/70 1.50 SetPoint, 0ft ead, 23ft end
Stop at 40ft 6:00 (63) Diluent 10/70 1.50 SetPoint, 0ft ead, 21ft end
Stop at 30ft 9:00 (72) Diluent 10/70 1.50 SetPoint, 0ft ead, 19ft end
Stop at 20ft 31:00 (103) Diluent 10/70 1.50 SetPoint, 0ft ead, 17ft end
Surface (103) Diluent 10/70 -30ft/min ascent.

Off gassing starts at 237.8ft

OTU's this dive: 174
CNS Total: 78.7%

[Joshua Smith]

Conservatism= +2, setpoint 1.3. I see you're running 1.5. Do you actually dive 1.5?

[Joshua Smith]

I love you, man!

can i play?
i spent the last few years being the oc token
with many ccr partners on some pretty nice dives
nothing legendary

but the admiral sampson was pretty cool

not once, EVER (as in never) did the ccr buddies clear before me
oddly, not once, EVER (as in never) did i (on oc) clear before my team
all in together
all out together
every time

maybe my numbers were a few shorter
maybe the ccr dude was a few shorter
but if your deco comes down to a 4 minute difference
and you actually believe it makes a difference
i got this bridge i have been trying to sell.......

[CaptnJack]

Greg, really, please just stop. 10/50 at 300ft? setpoint of 1.5 for 80mins of deco? If both your computers crap out I'd think that maybe today's not the day to push the deco with nominal tables. But to each his own, I'm not using a computer anyway.

[loanwolf]

Greg, really, please just stop. 10/50 at 300ft? setpoint of 1.5 for 80mins of deco? If both your computers crap out I'd think that maybe today's not the day to push the deco with nominal tables. But to each his own, I'm not using a computer anyway.

10/50 at 300' is a standard CCR mix a 1.0 PO2@300' with a END of 140'. What is wrong with that?

If you read the set point is 1.3 for the dive and 1.5 for deco. that is only for deco. Not the bottom time. you start up and have to start adding O2 as you PO2 fall's off as you are going up then stabilize it at your first long stop and run a 1.5 or their abouts the rest of the way up. all within recreational limits.

[loanwolf]

Conservatism= +2, setpoint 1.3. I see you're running 1.5. Do you actually dive 1.5?

josh I do run a 1.5 for deco sometimes higher as does eveyone I know we all crank up the PO2 on deco. it will get you out of the water a little faster CNS loading is pretty much the same as if you do the PO2 spikes with OC. You will get out about 7 min faster on a 300' dive.

[Joshua Smith]

10/50 at 300' is a standard CCR mix a 1.0 PO2@300' with a END of 140'. What is wrong with that?

If you read the set point is 1.3 for the dive and 1.5 for deco. that is only for deco. Not the bottom time. you start up and have to start adding O2 as you PO2 fall's off as you are going up then stabilize it at your first long stop and run a 1.5 or their abouts the rest of the way up. all within recreational limits.

First off, 140' END is a bit much, especially on a rebreather, where mix is so cheap. I like to keep mine < 100.

Secondly- your dive plan calls for 80 minutes at 1.5 p02. That's not taught, or recomended, by anyone. Yes, Mel taught me to do the reverse 02 flush @ 20fsw, and I do like to bump my P02 up on deco. But Mel also taught me NOT to account for that in the dive plan, to build in conservatism. If you're exposing yourself to those P02's on a regular basis, you're playing chicken with ox tox. I would go so far as to say that I find it reckless.

[CaptnJack]

As Josh said, 140ft END on the CCR diver is silly. Then compared with 10/70 for the OC diver along with 20/25 and 40% intermediate deco gases (which look more like possible bailout gases to me than prudent OC choices). 20% more He on a 20min BT profile is for sure apples to oranges. Nevermind running a setpoint of 1.5 for way over an hour continuous. You don't need to prove anything and all these vplanner profiles aren't proving anything anyway. I suppose if nothing else this thread is a way to appreciate good training in lieu of the internet.

[loanwolf]

10/50 at 300' is a standard CCR mix a 1.0 PO2@300' with a END of 140'. What is wrong with that?

If you read the set point is 1.3 for the dive and 1.5 for deco. that is only for deco. Not the bottom time. you start up and have to start adding O2 as you PO2 fall's off as you are going up then stabilize it at your first long stop and run a 1.5 or their abouts the rest of the way up. all within recreational limits.

First off, 140' END is a bit much, especially on a rebreather, where mix is so cheap. I like to keep mine < 100.

Secondly- your dive plan calls for 80 minutes at 1.5 p02. That's not taught, or recomended, by anyone. Yes, Mel taught me to do the reverse 02 flush @ 20fsw, and I do like to bump my P02 up on deco. But Mel also taught me NOT to account for that in the dive plan, to build in conservatism. If you're exposing yourself to those P02's on a regular basis, you're playing chicken with ox tox. I would go so far as to say that I find it reckless.

the dive plan for a 300' dive is only 70 min of deco' not 80 and half of that is at 20' which you will be either on OC or CCR running a 1.6. So the only difference is less on the bottom 1.3 CCR / 1.4 OC and more on the first 30 min of deco but you do not have a 1.6 spike at 80' as OC does. So if you average that out you will see that most of the time the CCR diver even running a 1.5 on deco is getting hit with the same or less O2 during the dive. It is just at a flatter rate. still well within limits for both.

Running your PO2 up on deco is not a problem as long as you keep you CNS clock in check. the difference on a 300' dive for 10/50 to 10/70 is 10 minutes of deco longer for the 10/70. You saturate with He much faster and pay for it. 140' end is not for all yes, but will you run air on a 140' dive on OC? when you really push deep your end will get much deeper than that.

[ljjames]

There are different methods out there.

WHY run it at high set point for these big dives that you know you are gonna be hammering on your lungs?

why not run a low setpoint... say... .7 and then deco with high setpoint? Full toggle for Deco. Reverse flush for Highs at 20', then Nitrox Dil or breath it down with BOV flush for 'breaks'. Run it essentially just like an OC dive with regards to PPO2...

The guys in FL doing 400's are in warmer water and yes, some have habitats, but thats how some of them are doing it. the O2 clock stuff you guys are talking about is nothing compared to what they are doing. We're talking 375%... not something we can really do here in our cold water. We're just not in the water as long as they are. (8-12hrs - i'm talking full CCR guys here not the WKPP)

There is no need for the hight setpoint on these dives. You pay for it at the beginning or you pay for it at the end.

The benefit for deco is marginal either way. The benefits of CCR is not in the deco, it's in gas management

[CaptnJack]

(8-12hrs - i'm talking full CCR guys here not the WKPP)

<snip snip>

The benefit for deco is marginal either way. The benefits of CCR is not in the deco, it's in gas management

WKPP guys are in the water a reaaaaaly long time, like full liquid diet for days beforehand durations. But otherwise agree a few mins difference on deco isn't particularly relevant, even 15mins is trivial compared to what people are doing in much warmer water.