Just Started Diving Again and Found out I'm an Idiot ?????? Need advice.....

[burjee1]

rusty bellies are old male gag's that hermaphrodite from male to female

 

[DevonDiver]

I've never seen it any other way than %O2/%He.

ANDI teach it the other way (i.e. 20TX26 = 20% Helium 26% O2). This follows the wider-used (outside of diving) convention to list the inert gas components first.

 

[Dsix36]

ANDI teach it the other way (i.e. 20TX26 = 20% Helium 26% O2). This follows the wider-used (outside of diving) convention to list the inert gas components first.

Oh crap, now Giani will start all over again with how dangerous it is to not have some CE approved method of listing the gas contents in a standard way all over the world. Probably with permanent tank markings and a MOD welded into the tank neck.

I should start my own agency just to fight the normal crowd.

 

[Wookie]

ANDI teach it the other way (i.e. 20TX26 = 20% Helium 26% O2). This follows the wider-used (outside of diving) convention to list the inert gas components first.

You are TecRec and ANDI. How do you teach it?

 

[dumpsterDiver]

Hey Everyone,

I just started diving again this year after some years off and need some advice.

I recently went on a spearing trip that would be 5 dives of 100-150 ft. I brought HP120's with 28 and 40's of 36 and 30's with 80/20 for deco.

I was promptly told that only Idiots dive 80/20 anymore and I might as well deco on air. I found that hard to believe but everyone on the boat was in agreement. The last time I dove - the 80/20 was said to be a good idea.

So, What is the 2013 Consensus - I want to be as safe as possible, the cost of the extra 20% of O2 is no object and I dont want to be the donkey on the boat next time.

Thanks!!!

Steve.

With all the variables and craziness of spearfishing, I don't think it matters too much if you are using 80 or 100%. I think I prefer 100%.

If you were diving with good spearfisherman, they would care what you shot and not give you crap about 80/20! Did you shoot more than them and that was their only recourse was to whine about deco gas?

 

[lindenbruce]

Hi,

Yes, I meant to say 80% O2 for Deco. The others were all on 50% or 100% and I guess I don't see the foul in being in between? It was all the talk on the boat for two days though. I guess I will keep quiet or go 100% next time.

Please don't be quiet. Your life is at stake here. Using a PPO2 of 1.6 for a non-working deco(Ie; none to minimal physical exertion) here are the MOD's for your O2 percentages.

50% O2 MOD is 72feet with a PPO2 of 1.6
80% O2 MOD is 33feet with a PPO2 of 1.6
100% O2 MOD is 19feet with a PPO2 of 1.6

So as you can see there is a difference of 53 feet of depth between a 50% mix and a 100%. So please don't be quiet and make sure of your MOD for the mix you are using. You don't want to be using 100% O2 for a deep deco. You will have oxygen toxicity in no time at all at those depths on 100% O2. So if you do use 100% O2 for deco make sure you are no deeper than 19 feet. That's why 50% is such a popular mix for deco. You can go on it at a much deeper depth. And if you do have a catastrophic back gas failure you can still hit the 50% at deeper depths. Just make sure you are making haste to reach the MOD. Don't loiter around, get your butt up to the MOD now. B.

 

[Instructor_Tom]

personally I would dive a 21% O2 / 40% he on my primary gas to deal with Narcossis, have a 50% O2 bottle to start my Deco at 70ft (PO2 at 1.6) and switch to 100% O2 at 20ft

I'd also run the dive on VPlanner to compute all my gas requirements and run times.

Sent from my iPad using Tapatalk HD

 

[DevonDiver]

You are TecRec and ANDI. How do you teach it?

On a given course, I teach as per that agency. I'd always explain the alternatives and realities though. When just diving, not teaching, I'd go with the methods of the team - more often than not, that'd be O2/He.

 

[Dr. Lecter]

You're not alone in choosing 80% over 100% for shallow deco stops; the difference in deco time between doing my last stop on 80% vs 100% is irrelevant, and 80% lets me drop as low as 30' should surface conditions require it. I also feel much better about cranking 80% all the way up to a tank's working pressure, and there's no need for my blender to have a booster. Not to mention that O2 gives me the willies and the lower the O2 % the safer I feel, though I recognize that 80% needs to be treated exactly like it's 100% in terms of handling.

 

[dumpsterDiver]

personally I would dive a 21% O2 / 40% he on my primary gas to deal with Narcossis, have a 50% O2 bottle to start my Deco at 70ft (PO2 at 1.6) and switch to 100% O2 at 20ft

I'd also run the dive on VPlanner to compute all my gas requirements and run times.

Sent from my iPad using Tapatalk HD

Really, you do all that (3 tanks) for a spearfishing dive in 135 ft? Seriously... for spearfishing?