Huw Porter wrote"
> For single square(ish) profile dives, my tables (Buhlmann with GF 20/90)
> give more deco than my Suunto Stinger.
> 27 minutes at average depth about 33m on nitrox 32. (ran on the schedule
> for 25 at 35 fudged slightly)
>
> Table deco:
> 2 @ 24
> 1 @ 15
> 1 @ 12
> 1 @ 9
> 5 @ 6
>
> Stinger ceiling cleared during the 9m stop.
There's something odd about what you wrote, or at least what I think you
wrote. If I read you correctly, you used your tables to set the profile for
a 25 minute dive at 35 meters, about 115 feet, on nitrox 32, which yielded a
deco schedule totalling 10 minutes with the first stop at 24 meters.
First, I do deep stops beginning at about half my maximum depth. In this
case, I would not have done any stops until somewhere around 15 meters,
about 50 feet. Interestingly, this was the perfect profile to demonstrate
why. During my 30 foot per minute ascent, some compartments continued to
load and just before I hit 50 feet, I got an extra minute of deco. In other
words, one or more critical compartments were still loading at depths below
50 feet. Further, when I ran a 25 minutes dive to 115 feet on 32% on my
computer, it reported only 3 minutes of deco at 10 feet, added a minute
before I hit 50 feet and dropped back to 3 minutes before I got to the
mandatory 10 foot stop. When I ran this dive the way I actually would have
done it, with 2 minutes stops every 10 feet beginning at 50 feet with a 3
minute safety stop at 15 feet, my computer cleared deco during the 30 foot
stop and was nearly out of the caution zone by the time I hit the surface.
I suspect we're talking apples and oranges here. I find it hard to believe
that your tables and/or computer are that much more conservative than my
Oceanic and Genisis computers (which both use the same algorithm).
If you'd like to test the issues I have with the Suunto, do a couple of
dives on nitrox at a ppo2 OF 1.4 and 1.5 and compare them to the same dives
one on tables. If you decide to do this, please let us know how it turns
out.
Lee
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