On 06 Oct 2014, at 11:13, Willem Ferguson <[email protected]> wrote:
Willem, > The current position of the black line suggest that it perhaps indicates the > equilibrium partial pressure for all inert gases (He + N2) combined?? > Similarly, the dark green portion of the bar graph seems to indicate the > present combined partial pressures for He + N2. Indeed, everything is for N2 and He combined. > But the bar graph surely only pertains to the nitrogen fraction because > offgassing for nitrogen and for He follow different patterns, He requiring > much longer offgassing times?? Still, it shows N2 plus He as this is what is relevant for Buehlmann-like algorithms. > I suspect the gradient factors apply only to the nitrogen partial pressure? Again, they apply for the sum. To compute the M-values, you are supposed to take the (weighted by the percentage of the gases) average of the a- and b-parameters. Have a look at the code in deco.c which I hope explains it, see the function tissue_tolerance_calc specifically. Best Robert
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