Posted by MHK on October 30, 2000 at 10:06:01:
In Reply to: Re: Half as bad posted by Ken Kurtis on October 29, 2000 at 23:40:27:
Posted by Ken Kurtis on October 29, 2000 at 23:40:27:
To compute the actual theoretical safety margin, you'll have to figure it based on controlling tissue, tissue half-time, M-values, etc., etc. etc. And you'll also have to cover the debate on whether or not a diver at an NDL at 100' is at the same DCS risk as a diver at an NDL limit at 75'. Is saturated saturated and the risk the same?
Ken,
I've been trying hard not to get into too much of our private conversations to spill into this thread, but this one I needed to address.
You have the majority of the proper issued defined but my sense is you aren't understanding, or willing to accept, the conclusions. For example you are asking for * actual theoretical*, the oxymoron notwithstanding, you and I both know that ALL tables and computers are statistical probabilities of the Buhlman algorithm. And if memory serves me you even cover this in your dive briefing ( or atleast words to that effect ) and suggest that since they are probabilities your suggest conservatisim. ( FTR, I agree with the conservation recomendation ), but where I'm confused is if you acknowledge the statistical variance with respect to air tables, why are you asking us to prove with certainty the Nitrox model. I have no problem if you want to create a hypothetical dive profile and I'll compute all the M-values of each of the tissue compartments.. But you know as well as I do that there are other factors that are contributory for a bends hit, physical fitness, dehydration, obessity, exercision just to name a few..
But if you are willing to stipulate to all other factors being equal than it's clear the M-values will favor Nitrox and even more clear to teh extent that any of the above factors come into play.. Accordingly, if you take Oxygen Toxicity out of the equation ( which is mitigated substantially with respect to the Yukon ) there simply is NO arguement ( statistical or otherwise ) that you can credibliy advance and if you want you and I can do the numbers together and post the results..
Ken was a math major in college and is very good with numbers and should have no problem computing the algorithms..
I'm trying to stay out of this one, but I can't let statements like this go unchallenged..
Later