Free VPM Deco Software

[Lost Yooper]

Just as a matter of comparison for anyone else lurking, my Z Planner spit the following out with zero conservatism:

150', 45mins, 21/35, 50% @ 70', O2 @ 20'

120ft for 1:15
110ft for 1:15
100ft for 1:15
90ft for 1:15
80ft for 1:15
70ft for 1:15 Nitrox 50.0
60ft for 1:15 Nitrox 50.0
40ft for 2:00 Nitrox 50.0
30ft for 8:00 Nitrox 50.0
20ft for 10:00 100% Oxygen
10ft for 18:00 100% Oxygen

TOTAL DECO TIME: 47 minutes.

A lot more conservative. Just for the record, I don't use 10' as my last stop. I set the program to use 20' as the last stop so we're on the high PPO2 longer (i.e. to keep the O2 window open longer so to get the most out of the high PPO2). None of these programs give you credit for the longer duration at 20' or 70' (on 50%), but I guess they can't take everything into consideration.

Mike

 

[blacknet]

Hello,

With everything turned off GAP will get you out in 35 mins.

Ed

 

[blacknet]

Hello,

It's my understanding that the longer stop at 20' and 70' would 'break' the assumptions for the traditional algorithms and I see no need to switch to the last stop at 20' but that gets into an area I would rather not see brough up on this list.

Ed

 

[Lost Yooper]

Ok. I sure like how the VPM starts deeper though. That is really important for mix since it likes to come out faster.

Later.

Mike

 

[blacknet]

Hello,

Pure speculation as i've not seen the code/algorithm they are factoring in some deep stops and less conservatism than the classical programs do. Now as for being correct in stating the deep stops will help get you out faster is abit beyond my level, would have to pass that one along to the dr's and rainreg for discussion, then read the conclusion at the end

Ed

 

[Lost Yooper]

Yes, it certainly does break the assumptions of the traditional stuff. At 1.6, you are offgassing at the greatest (and safest) rate.
I agree with you, and I warn everybody that doing this stuff wrong will kill you. There can be a lot more involved including back gas breaks from O2 and other things that can be critically important not being discussed here.

Mike

 

[blacknet]

Hello,

Interesting to note, I ran the same profile with decoplanner this is the results

feet/stops/mix
70/1/50%
40/4/50%
30/6/50%
20/24/100%
That was all things turned off, last stop at 20' and computer algorithm.

Ed

 

[Lost Yooper]

Hmmm. Deco Planner gets you out in 35 mins too. So, DP, ZP, and VP are all getting you out pretty close to the same time, but with V Planner starting just a bit deeper than Deco Planner. The rule of thumb for beginning deep stops is 80% of the profile in ATA (in this case about 110' or so). It's not that critical so long as you are ascending less than 30FPM.

That's fine with me.

Mike

 

[blacknet]

Hello,

And USN is 45 mins (5+7+33).

This type of profile is a standard classical profile. Where you get into the differences is looking at the extended times and other factors. One thing I did like about the abyss software; you could add your WORK LOAD, water/air temp and other similar variables. No place do I see that option in the above mentioned packages.

If you ran the same mix at the same depth for say 120 min or more then you'd probably see some vastly different figures and seriously confuse most people.


Ed

 

[Lost Yooper]

I wouldn't doubt it, but I ain't into that stuff up here. You'd die of hypothermia before you got done with deco. :cold: We add a few things, both into our deco profiles as well as the dive, to combat against detrimental factors such as cold and exertion.
We plan for the deepest depth attainable, but only stay at that depth for a minute or two (to see the rudder of a wreck or something), and we spend 5 mins at 70' instead of the 1-2 mins the program tells us. We don't exert (purposely) and, of course, stay well hydrated. We might stay in the water at the surface for a bit after a dive and avoid post dive exertion for 20-30 mins. There's a lot of tricks you can do to beat DCS and sub DCS so long as you don't have any unidentified preconditions.

Jeeze, it's 1:30am. I'm going to bed.

Later.

Mike