Deco for Divers: RGBM vs other algorithims

[filmguy123]

Wanted to get a discussion started on this after browsing through Mark Powell's "Deco for Divers" and how RGBM is one of the newest deco algorithms... it seems to have its merits, even though I've also heard and read that it doesn't seem to have any PROVEN benefits over other models...

What is your preferred algorithm and why? RGBM - too conservative, or the latest in study?

 

[tbone1004]

buhlmann with gradient factors due to being able to adjust conservatism to avoid favoritism for deep stops

 

[Scott]

Bühlmann ZHL-16C with Gradient Factors for a few reasons tbone already mentioned.

 

[Chris H]

I use the Buhlmann ZHL-16 as well. I don't have a hose in the race, but this presentation is worth a watch.

 

[filmguy123]

Interesting!

What about for more intermediate diving? (Advanced rec diving)?

 

[Freewillow]

Bühlmann with GF (70/80) for air or Nitrox. If you have any doubd left after viewing Dr Mitchell presentation...............well, replay it again

 

[KenGordon]

It does not really matter. For stuff in the 'recreational' range the different algorithms will mostly agree if you choose what conservatism you use carefully. It all comes down to choosing who to trust, then maybe deciding how long you are prepared to spend on deco stops.

Other features such as multiple gases, helium etc are much more important.

Today I will be diving a Buhlmann primary and a (supposedly) RGBM backup.

 

[Patoux01]

What about for more intermediate diving? (Advanced rec diving)?

Why would Buhlmann not be appropriate for those dives?

 

[Centrals]

I don't care what others are using but I will just stick with Buhlmann for rec or tec dives.

 

[scubadada]

That is a really great presentation, I enjoyed it very much, thanks for posting.

"Recreational" (no stop) diving does not require decompression stops, the safety stop is an elective, conservative addition to the profile. For no stop diving, the various decompression algorithms will simply give you varying lengths of NDL. All have proven to be "safe", I know of no evidence to the contrary. There are unexplained episodes of DCS using all decompression algorithms.

The decompression part of the decompression algorithm comes into play when the NDL is exceeded. The excellent presentation by Simon Mitchell pertains to this topic.

Dr Mitchell's conclusions appear to be well supported. It is interesting that he shared his personal decompression algorithm choice during the presentation and puts his beliefs into practice, Buhlmann ZHL-16C 50/70-75. This GF lo is higher than is often mentioned. As an example, the Shearwater Petrel/Perdix default is 30/70, a relatively common choice for technical divers.

I would be very interested if others would share their choice and reasoning of their GFs used for decompression diving.