Rec Trimix

[Ben_ca]

PADI would get you out quicker (sorry only have metric tables)

90 m - 20 mins
3 m - 3 mins

Flame on
:losecool:

 

[lamont]

PADI would get you out quicker (sorry only have metric tables)

90 m - 20 mins
3 m - 3 mins

Flame on
:losecool:

300 ft for 20 mins and you only do 3 mins of deco at 10 ft and hop out? you must have unreal vascularization.... =)

 

[Kevrumbo]

Either that or immediate access to a Recompression Chamber...

 

[Ben_ca]

300 ft for 20 mins and you only do 3 mins of deco at 10 ft and hop out? you must have unreal vascularization.... =)

oppsss 30 Meters... 90 FT My Bad

 

[smartecosse]

well just wasted half an hour reading all of these posts -

made a boring day at work pass much quicker so thanks to all..

can't really see the point myself of mix at shallow depths. as one poster pointed out do 20 odd dives at that depth and you start to become "more funtional" at that depth. (dont flame me cos of the bad wording!)
However if i had nice cheap access to helium then i really wouldnt mind diving a weak mix on 30m odd dives, after all its not going to hurt anything except the wallet
am pretty sure if i wrote a spec for PADI on "blowing the perfect donut bubbles" some muppet would take it. trimix rating is the latest card that people seem to want. deep air diving is for some and not for others.

personally i dive on both twins and a CCR. Am happy in the 60m range on air on both. But then i live & work in thailand, the water temp even at that depth is about 28 oC and its nice and light as well past the 70m mark and it would be mix... on either thetwins or the evo

my tuppence worth

 

[Soggy]

I think you need new deco software...holy moly that's a lot of pointless hanging around. I can do a 45 minute dive on your GAP schedule.

Here's V-planner:

Decompression model: VPM - B

DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0ft
Conservatism = + 1

Dec to 100ft (2) Nitrox 32 50ft/min descent.
Level 100ft 28:00 (30) Nitrox 32 1.29 ppO2, 81ft ead
Asc to 10ft (33) Nitrox 32 -30ft/min ascent.
Stop at 10ft 3:00 (36) Nitrox 32 0.42 ppO2, 4ft ead
Surface (36) Nitrox 32 -30ft/min ascent.

Off gassing starts at 57.1ft

OTU's this dive: 45
CNS Total: 16.6%

91.0 cu ft Nitrox 32
91 cu ft TOTAL

----

Decompression model: VPM - B

DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0ft
Conservatism = + 1

Dec to 100ft (2) Triox 30/30 50ft/min descent.
Level 100ft 28:00 (30) Triox 30/30 1.21 ppO2, 34ft ead, 60ft end
Asc to 10ft (33) Triox 30/30 -30ft/min ascent.
Stop at 10ft 3:00 (36) Triox 30/30 0.39 ppO2, 0ft ead, 0ft end
Surface (36) Triox 30/30 -30ft/min ascent.

Off gassing starts at 58.8ft

OTU's this dive: 41
CNS Total: 14.5%

91.0 cu ft Triox 30/30
91 cu ft TOTAL


Heck, the NDL tables give you 30 minutes if you use an EAD of 80 ft or 25 mins if you use an EAD of 90 ft...

RH, since you use the GAP Deco Program, here's the derived "RGBM On-the-Fly" algorithm alluded to earlier, for square profiles or depth averaged profiles in the 80-110fsw range:
http://www.dekodive.bloguje.cz/147339_item.php
Here is a dive I would do on 32% OR 30/30 Triox using the above:
100 - 30 mins
40 - 1 min
30 - 3 min
20 - 10 min

Compare to Soggy's (Minimum Deco as taught by GUE and 5thd-x):
http://www.scubaboard.com/showpost.php?p=1851083&postcount=160
32% OR 30/30:
100 - 30 mins
50 - 1 min
40 - 1 min
30 - 1 min
20 - 1 min
10 - 1 min

As you can see Minimum Deco will get you out of the water sooner (buoyancy and ascent control using this model is extremely critical), while RGBM in this instance seems to be more conservative and comparatively forgiving. Suggest you use whichever you feel comfortable with, while using your proprietary GAP Program as a sanity check.

 

[TheRedHead]

Thanks, Kevin, for the very interesting comparison.

 

[lamont]

can't really see the point myself of mix at shallow depths. as one poster pointed out do 20 odd dives at that depth and you start to become "more funtional" at that depth. (dont flame me cos of the bad wording!)

I've got a lot more than 20 dives to that depth. I understand becoming more functional at that depth. I've got it to the point now where mostly I just make sure to memorize whats on my SPG when I check it to work around the short-term memory loss. And a little narcosis at 100 fsw is kind of nice if a big shark shows up and checks you out... The point is, though, that I haven't stopped getting short term memory loss down there, I've just learned ways around it. I've got all kinds of other tactics for dealing with task loading and perceptual narrowing as well. I'd prefer to simply not experience that, though. If cost were not an object I'd dive 30/30 to 100 fsw all the time because the idea that you're a better diver if you can "hold your narcosis" is idiotic. Its exactly the same as people who brag about how drunk they were when they drove home. If you want to prove how much you can handle while you are altered, do it on dry land -- check out www.burningman.com -- its a nice safe place there with no water around it for miles where you can get as altered as you want.

 

[TheRedHead]

I think you need new deco software..

The deco would be substantially shortened with EAN50 or EAN80 for deco. I don't have the software on this computer to run it right now.

 

[Soggy]

The deco would be substantially shortened with EAN50 or EAN80 for deco. I don't have the software on this computer to run it right now.

Agggggg!!!!

There is no decompression obligation on that dive (100 ft, 30 mins, 32% or 30/30). What part of this do you not understand? It is an NDL dive. 3-5 minute safety stop, just like PADI says....that's it. Nothing more. This is basic Nitrox class kinda stuff. Stop thinking about the helium and pull out your tables. You don't need 50% on this dive (and you never need 80%...the most illogical mix ever). I even provided the vplanner profile a couple posts ago....on +1 conservatism even!