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on 13/2/02 1:28 PM, David Burnworth at xlh883@ea*.ne* wrote: > In short, can a software program like DecoPlanner benefit the every day > recreational diver that occasionally goes deeper than say 60 feet for example. Hi David, here's my .02, (corrections invited + encouraged) Even on (supposedly) no deco dives, I think it's still instructive to see info like: Where the deco zone starts for a given profile. At what depth a deep stop is going to help (not hurt) you How are the tissue compartments doing at certain times in the profile What sort of overpressure gradients am I generating, and do I need to adjust them ? Particularly as regards to depth of first stop on traditional tables/wrist computers. Combine the above with some of George's other advice on things like ascent rates, particularly from 6m to the surface and I think there's a lot you can do to better shape your ascent curve (as in a better deco shape) even for these ND dives. George, is it too embarrassing to work through an example for a weenie dive like this ? ;-) For instance take an NDL dive (according to an air table for simplicity) of 30M for 20min, though 32% would be better and 30/30 even better. D RT 30m 15 4.5m 21 Assumes 10m/min asc rate and a 3 min ss at 4.5m DecoPlanner gives you: D RT ST 30m 15 15m 22 1 12m 23 1 09m 24 1 06m 25 1 03m 27 2 (GFs 15/85) David, you can vary the Gradient Factors in DecoPlanner to get different run times depending on your own response to the deco. If you were to graphically plot the ascent (say on your Vyper PC kit) with one versus the other you will see a much more natural curve with the DecoPlanner profile. The deep stops (starting at 15m) are allowing more time for the N2 to get out in solution rather than bubble out at 4.5m. You are definitely going to come out of the water cleaner on the DecoPlanner type profile. Common sense would tell you that blowing up from 4 Ata straight to 1.45Ata can not possibly be as good for you as staging the ascent with the 1 minute mini stops. Since you are Nitrox rated, you may as well use that for a slightly shorter RT and less accumulated N2. Or just dive it on air tables for extra safety if you think you need it (age, weight, general fitness, multiple dives, cold etc). DecoPlanner also automatically tracks your CNS and OTUs if you are rep diving Nitrox. Comments anyone ? George you have said that your deco is longer than most people's for shorter dives, would you be recommending even more than this ? (Note I mean for the diver of "average" dive fitness, weight, perfusion etc) For instance would you still do a slow ascent from the 3m stop to the surface (1m/min maybe ?) Or perhaps roll both of the 6 and 3m stops into a single slow ascent to the surface ? (Maybe 6 minutes total from 6m to the surface) Or is all of this unnecessary for a nothing dive ? Would you take more time on air vs 30/30 even though they plan out pretty much the same on DecoPlanner ? TIA regards dean laffan real world productions melbourne, australia ph +613-9419-3966 Mobile 0418-525-315 -- 'The Internet is a fad ... it's not part of our core business' - Bill Gates 1997 -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
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