Best Mix VS Standard Gasses (split from a GUE fundies course report)

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NC diving can be very frustrating. I have booked on a number of charters over the last few years and have been blown out every time. I have also booked hoping to get to a deep offshore wreck several weeks in a row, and dove the shallow inshore wrecks each time. It gets frustrating.

Now that I primarily dive CCR, there are a few charters I can not dive on. For gas planning on CCR I always use air dil in NC since we don't get deeper than 130' and I'm good to 160' or so before I feel like I need Tx. I also only need a 40 for bailout since we won't be doing 2 hour runtimes. For diving OC, you bring tanks filled to the deepest possible wreck you might hit and hope you get to see it.

I have never sipped to GUE kool-aid so far, but I'd like to take fundies at some point. I don't foresee me adopting a hardcore GUE way of diving or gas selection, but I have not had any serious OC training in a very long time and the GUE intrigues me.
 
My question still stays. For your charter with max depth of 125', what is your best mix in your single tank, what is the NDL? And I'd you see an anker at 135', will you go there?

In NC, if I were diving OC, I would do what everyone else does that goes there - take 2 tanks full of EAN30. And not lay on the bottom. And they don't take rec charters to anywhere with a bottom deeper than 125', so no anchor there at 135.

I asked specifically about going to do a NC dive. A GUE diver with no more than Fundies training, who is adhering to their training. I'm not getting dragged into what-ifs of other places. I only threw out a different location to illustrate that NC is not unique in the variability of what you have to plan for.

What I seem to have gathered so far is that this hypothetical GUE Fundies grad who wanted to dive NC (but adhere to his training) would:

- take their own tanks filled with TX30/30 - and possibly use them on 2 x 70 - 80 foot dives.

or

- take their own tanks filled with EAN32 and not dive deeper than 100'. If they end up on a site with nothing but blue water at 100', then they'd stay out, or jump in, see what's up, and get out. Fortunately, there aren't that many sites that are that deep and have that little relief.

If their only option for tanks was to rent what the dive shop there offers, they would just not dive - because the choices are Air or EAN30.

Have I captured all the options and accurately? Again, I'm asking what the official GUE training standards would say.

As @TrimixToo noted, Standard Gases are usually only thought of in the context of tech diving. But, my understanding is that GUE standards mandate use of Standard Gases on ALL dives - even purely recreational sport dives. So, how does that work out for recreational sport divers? Based on the number of divers I see diving the NC wrecks, going deeper than 100' and seemingly just fine with no helium - not to mention all the people I see who dive shallower than 100' using Air (instead of EAN32), it SEEMS to me like GUE Standard Gases are pretty limiting - not making "it easier" like the GUE people keep telling me. At least, for sport divers anyway.
 
NC diving can be very frustrating. I have booked on a number of charters over the last few years and have been blown out every time. I have also booked hoping to get to a deep offshore wreck several weeks in a row, and dove the shallow inshore wrecks each time. It gets frustrating.

Now that I primarily dive CCR, there are a few charters I can not dive on.

Just curious, what charters down there can you not dive on CCR?
 
In NC, if I were diving OC, I would do what everyone else does that goes there - take 2 tanks full of EAN30. And not lay on the bottom. And they don't take rec charters to anywhere with a bottom deeper than 125', so no anchor there at 135.

I asked specifically about going to do a NC dive. A GUE diver with no more than Fundies training, who is adhering to their training. I'm not getting dragged into what-ifs of other places. I only threw out a different location to illustrate that NC is not unique in the variability of what you have to plan for.

What I seem to have gathered so far is that this hypothetical GUE Fundies grad who wanted to dive NC (but adhere to his training) would:

- take their own tanks filled with TX30/30 - and possibly use them on 2 x 70 - 80 foot dives.

or

- take their own tanks filled with EAN32 and not dive deeper than 100'. If they end up on a site with nothing but blue water at 100', then they'd stay out, or jump in, see what's up, and get out. Fortunately, there aren't that many sites that are that deep and have that little relief.

If their only option for tanks was to rent what the dive shop there offers, they would just not dive - because the choices are Air or EAN30.

Have I captured all the options and accurately? Again, I'm asking what the official GUE training standards would say.

As @TrimixToo noted, Standard Gases are usually only thought of in the context of tech diving. But, my understanding is that GUE standards mandate use of Standard Gases on ALL dives - even purely recreational sport dives. So, how does that work out for recreational sport divers? Based on the number of divers I see diving the NC wrecks, going deeper than 100' and seemingly just fine with no helium - not to mention all the people I see who dive shallower than 100' using Air (instead of EAN32), it SEEMS to me like GUE Standard Gases are pretty limiting - not making "it easier" like the GUE people keep telling me. At least, for sport divers anyway.

Fundies only certifies you to dive 32%, and to a max depth of 100 feet. GUE divers adhering strictly to protocol, would need a Rec 3 cert (certifies you to use 30/30 and to go to 130 feet), or a Tech cert.

Basically, the only "standard gas" you are qualified to use after Fundies is 32%. That makes the choice very easy since you use it for everything. :)
 
Is helium even available in NC? I've never heard of anyone getting any down there?

As shocking as it might seem, most fundies graduates know there's no accessible helium in NC. So if they booked a trip there despite that fact, I suspect they're prepared to fall back onto their original training and use EAN30 with a max of about 120ft.
 
Is helium even available in NC? I've never heard of anyone getting any down there?

As shocking as it might seem, most fundies graduates know there's no accessible helium in NC. So if they booked a trip there despite that fact, I suspect they're prepared to fall back onto their original training and use EAN30 with a max of about 120ft.

It is basically "available upon request". At least, at Olympus Dive Center it is. I.e. call well ahead to request it. Also, there is a shop in Wilmington (the name is escaping me right now, but I got TX fills there in March without doing any pre-arranging) that has it all the time, if you're diving out of there. If you're going out of Hatteras, you better bring everything you need.

So, GUE offers OW training, but the reality is that nobody really does that? Everybody starts with PADI/SDI/SSI/NAUI/ABC/XYZ and then starts with GUE with Fundies?
 
A local dive shop owner told me I should be grateful for the GUE divers because the main users of He are GUE and CCR divers. The CCR divers don't buy enough for the the shop to bother with it but the GUE guys do. Thanks guys,
 
...So, GUE offers OW training, but the reality is that nobody really does that? Everybody starts with PADI/SDI/SSI/NAUI/ABC/XYZ and then starts with GUE with Fundies?

GUE Fundamentals is for already certified divers.
GUE Rec 1 is an O/W certification course, which has only existed for 6 or 7 years or so.
Most people start GUE training at Fundies. When you're looking for o/w training, you don't know what you don't know.
 
A local dive shop owner told me I should be grateful for the GUE divers because the main users of He are GUE and CCR divers. The CCR divers don't buy enough for the the shop to bother with it but the GUE guys do. Thanks guys,

That was exactly the problem I had last week in NC with trying to get He. Several of us were diving CCRs and the quantities needed were so small it just seemed like it wasn't worth the shop's time to get the He bottle and then do our tiny little fills.
 
In NC, if I were diving OC, I would do what everyone else does that goes there - take 2 tanks full of EAN30. And not lay on the bottom. And they don't take rec charters to anywhere with a bottom deeper than 125', so no anchor there at 135.

I asked specifically about going to do a NC dive. A GUE diver with no more than Fundies training, who is adhering to their training. I'm not getting dragged into what-ifs of other places. I only threw out a different location to illustrate that NC is not unique in the variability of what you have to plan for.

What I seem to have gathered so far is that this hypothetical GUE Fundies grad who wanted to dive NC (but adhere to his training) would:

- take their own tanks filled with TX30/30 - and possibly use them on 2 x 70 - 80 foot dives.

or

- take their own tanks filled with EAN32 and not dive deeper than 100'. If they end up on a site with nothing but blue water at 100', then they'd stay out, or jump in, see what's up, and get out. Fortunately, there aren't that many sites that are that deep and have that little relief.

If their only option for tanks was to rent what the dive shop there offers, they would just not dive - because the choices are Air or EAN30.

Have I captured all the options and accurately? Again, I'm asking what the official GUE training standards would say.

As @TrimixToo noted, Standard Gases are usually only thought of in the context of tech diving. But, my understanding is that GUE standards mandate use of Standard Gases on ALL dives - even purely recreational sport dives. So, how does that work out for recreational sport divers? Based on the number of divers I see diving the NC wrecks, going deeper than 100' and seemingly just fine with no helium - not to mention all the people I see who dive shallower than 100' using Air (instead of EAN32), it SEEMS to me like GUE Standard Gases are pretty limiting - not making "it easier" like the GUE people keep telling me. At least, for sport divers anyway.


Hi Stuart,

Let’s break this down a little. Fundamentals, on the certification side of things, is (on plastic) an OW Nitrox Class, with heavy emphasis on PPB/Intro to tech.

Having said that, if an OW/AOW diver took any nitrox class, and you put them in that scenario, what would they do?

Take some EAN3x and respect the MOD of the prescribed system they were taught (1.2-1.4)?

Take a weaker EAN2x and do the dive ‘best mix’ (since with AOW, it gets you to 40m/130ft)?

Or just take air?


What other training would your proposed GUE diver have?

Not all dives are GUE dives, and just having Fubdamentals doesn’t make one a GUE diver ....

To answer your direct question, at the fundamentals level, strictly following the rules of EAN32 at 1.2x is 32% at 30m.


I have a few questions for you,

You know that answer, why keep trying to hammer it down every time this comes up?

Why are you not happy with that answer?

If you were to come up with your own (it seems that you have) standard gases (GUE ‘standard gases’ aren’t a standard for other organizations. There may be similarities). What would they be, what would the reasoning for them, and when/where you you use them?

The only weird one that GUE uses is 30/30.

It doesn’t mix down with banked 32% (like every other bottom gas they use)

_R
 
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