Deep-stops vs shallow-stops: an interesting read.

[rob.mwpropane]

This thread has brought back memories...

Regardless, MultiDeco is fine decompression planning software. Like many, I use it with Buhlmann ZH-L16C with GF. It was fun being able to look at VPM calculations during all the past discussions about deep stops.

I like MD. As far as I know it's the only software that works on Android that can plan 2 dives?

iphone has ideco which is nice. (edit: I don't own an iphone.. so I really don't know)

 

[boulderjohn]

Ross had a particular affinity for protecting his revenue stream.

That has been discussed, but the problem is he makes the same money either way. He makes money if you buy V-Planner, sure, but you are more likely to buy his Multi-deco, which includes V-Planner and Buhlmann with GFs. During the deep stop wars, Simon Mitchell said he uses Multi-deco.

 

[L13]

Marroni's work is highly regarded by DAN Europe, but not by DAN America. DAN Europe supports deep stops in recreational diving; DAN America does not.

After I wrote the article about deep stops in decompression diving with Simon Mitchell, I asked him to help with a similar article on deep stops in recreational diving. He declined, saying that there was no research on it that was strong enough to draw a conclusion. That includes Marroni's research, which has been cited in the past for methodological flaws.

In Marroni's presentation in the video above:

• He gives evidence that peak bubbles correlates to surfacing GF
• He gives evidence that DCS correlates to surfacing GF
• He implies that therefore peak bubbles correlates with DCS
• He gives evidence that comparing a deep stop and no deep stop profiles with the same deco time:
  • deep stops reduce peak bubbles immediately after surfacing a little
  • no deep stops, using time for longer shallow stops reduced total bubbles over time (after the initial peak)
    • He doesn't follow through on the implications of this:
      • no deep stops had a lower surfacing GF --> should correlate with lower DCS
      • no deep stops had less bubbles over time and not much higher peak bubbles --> no deep stops may even be better with regard to bubbles over time

I agree with Simon Mitchell that overall the data/research is to weak to draw conclusions to strongly.

 

[dmaziuk]

In Marroni's presentation in the video above:

• He gives evidence that peak bubbles correlates to surfacing GF
• He gives evidence that DCS correlates to surfacing GF
• He implies that therefore peak bubbles correlates with DCS

... because before surfacing GF we had no idea that lots and lots of big bubbles correlate to clinical DCS.

 

[nadwidny]

That has been discussed, but the problem is he makes the same money either way. He makes money if you buy V-Planner, sure, but you are more likely to buy his Multi-deco, which includes V-Planner and Buhlmann with GFs. During the deep stop wars, Simon Mitchell said he uses Multi-deco.

Never bought Multi-Deco since I knew where the money was going and there were better alternatives.

 

[Seameadow]

For deep CCR divers, I would suggest to wait for the latest RF4.0 videos to come out. Some more interesting developments on Deco theory presented by Doolette particularly for dives deeper than 120m, that suggests GFs is not the best way to go.

Actually the navy developed Thalmann algorithm works better for deep CCR. So for a dive to 250ft the algorithm is the same as a 50/85 GF but when you compare it to a dive to 400ft there is a marked difference. The stops don't start deeper but there are longer stops overall and including longer deeper stops.

There were also interesting points on risks related to SPs and hyperoxia etc

 

[rob.mwpropane]

Never bought Multi-Deco since I knew where the money was going and there were better alternatives.

Like what? Please share what's better for an android phone (serious, I'd like to try something new).

Personally I use Subsurface on a PC or Multi Deco on my phone. I don't care about all the crap that the developer has done... I bet some people use McAffee and that guy was a nut!

 

[BoltSnap]

I don't care about all the crap that the developer has done..

What did he do that is so terrible, other than advocating a model you don't like?

 

[Wibble]

I like MD. As far as I know it's the only software that works on Android that can plan 2 dives?

iphone has ideco which is nice. (edit: I don't own an iphone.. so I really don't know)

MultiDeco works on Macs, IPhones, iPads, Ann Droid, and Win-Dos.

IMHO MultiDeco is the best of the bunch although the user interface can be quirky. Comes with a bunch of useful tools such as gas mixing.

V-planner is the old software with the VPM (Variable Permeability Model) algorithm which we've all moved away from to Buhlmann +GF.


We're all still arguing about different gradient factors to use. Something around 50:80 or 50:70 seems to be commonly used nowadays.

 

[rob.mwpropane]

What did he do that is so terrible, other than advocating a model you don't like?

Don't know, just murmurs on here. Idc.. I bought it and use it. I like it a lot, but I'm not opposed to trying something new.