Quote: (Originally Posted by
Janos)
I don't like GUE Ratio deco as comparing the profiles I find it scarily aggressive. It's generally a few more minutes less than VPM-B set to nominal conservatism.
Ratio deco is just pattern matching. I was asked by Woz to knock up some "rules" for OC air/Nitrox diving with 50% as a decompression gas. I called it "deco on the pie" because of my love of pork products. It produces results that are similar to 20/80 Bulhman
Link:
Deco on the Pie (DOTP) - YD Dive Forums & Scuba Community
I'm sure it's easy enough to do something similar for deep CCR dives, but what do you standardise on? What setpoint, diluent do you use? Is the setpoint steady or falling? What deco algorithmn do you use? what conservatism?
Janos
GUE type ratio deco is not very aggressive, as far as I'm aware. Perhaps you are talking about AG's ratio deco article? The deco described there can be a bit agressive in fringe cases, but in the vast majority of cases you'd still be in water about as long as with standard VPM/RGBM deco calculation, especially since you are well advised to round absolutely everything up by a healthy margin.
The whole point of DOTF, though, is that you don't need to do it exactly as the doctor prescribes. Nobody says you have to go out of the water when the calculated time is up, or that you can't bring O2 but deco out on a 50% schedule. The DIR-police also won't lynch you for doing another 10 minutes on 50/25% or 15 minutes on oxygen :-)