DIR- Generic DIR Standard Gases Logistics

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CAPTAIN SINBAD

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Greetings everyone. Id like to know that in your journey as DIR centric divers, how hard has it been to arrange for standard gases at various dive locations? I ask because I see a lot of tech-trips and destinations being advertised but when you reach out to them, the boats are often loaded with air compressors and banking O2 for repetitive diving. If you are TDI or mainstream certified, then you can adjust to the dive with whatever logistics the situation throws at you. If you are GUE or UTD then I would like to know how one would go about it. Any stories or true accounts would be greatly appreciated.
 
the point of standard gases was quite literally for logistics of mixing and that ended up making for convenient ratios to use for decompression. You bank EAN32 and the balance is helium. It essentially fixes your ppO2 and ppN2 at a limit that you're OK with and you don't have to pp blend O2 which is super annoying. You bank EAN32 and EAN32 only, and you only have to boost a little bit of O2 for your EAN50 bottle and O2. Super convenient.

So, what do you do when you don't have standard gases? You have three choices
  1. Dive a close ish ratio based on ppN2, ppHe, and depth, then pray. This is probably what UTD would tell you to do since you're supposed to blindly follow the almighty AG with whatever his god-like ability to decompress is feeling these days
  2. Accept that you'll have to dive a computer with whatever algorithm closely mimics whatever version of ratio deco that AG is selling as snake oil these days and get over it since you believe in whatever nonsense that deco strategy is, which is in direct opposition to the state of the art in decompression research.
  3. Don't dive

Don't like it? tough sh!t, that's the consequence of pigeon holing yourself to something that isn't adaptable.
The irony with UTD's ratio deco is they want you to be a thinking diver that can adapt with the dive profile, the problem is you can't do anything if the mix is wrong because the ratio's don't work. You obviously have room with a point or two in either direction which isn't really going to make much of a difference, but if they're diving something like 14/33 *air over 33% helium*, then you really don't have anything that you can do if you're going to dive RD.

Your fourth choice is turn your brain on and realize that there is nothing wrong with diving a computer. The anti-computer thing is based on a time when computers were both unreliable, and didn't have any control over your ascent profile. If you want to or have to stay at some depth for extra time, the computer doesn't care, it will adapt and keep on calculating for you.
 
the point of standard gases was quite literally for logistics of mixing and that ended up making for convenient ratios to use for decompression. You bank EAN32 and the balance is helium. It essentially fixes your ppO2 and ppN2 at a limit that you're OK with and you don't have to pp blend O2 which is super annoying. You bank EAN32 and EAN32 only, and you only have to boost a little bit of O2 for your EAN50 bottle and O2. Super convenient.

So, what do you do when you don't have standard gases? You have three choices
  1. Dive a close ish ratio based on ppN2, ppHe, and depth, then pray. This is probably what UTD would tell you to do since you're supposed to blindly follow the almighty AG with whatever his god-like ability to decompress is feeling these days
  2. Accept that you'll have to dive a computer with whatever algorithm closely mimics whatever version of ratio deco that AG is selling as snake oil these days and get over it since you believe in whatever nonsense that deco strategy is, which is in direct opposition to the state of the art in decompression research.
  3. Don't dive

Don't like it? tough sh!t, that's the consequence of pigeon holing yourself to something that isn't adaptable.
The irony with UTD's ratio deco is they want you to be a thinking diver that can adapt with the dive profile, the problem is you can't do anything if the mix is wrong because the ratio's don't work. You obviously have room with a point or two in either direction which isn't really going to make much of a difference, but if they're diving something like 14/33 *air over 33% helium*, then you really don't have anything that you can do if you're going to dive RD.

Your fourth choice is turn your brain on and realize that there is nothing wrong with diving a computer. The anti-computer thing is based on a time when computers were both unreliable, and didn't have any control over your ascent profile. If you want to or have to stay at some depth for extra time, the computer doesn't care, it will adapt and keep on calculating for you.

:facepalm::facepalm::facepalm::facepalm:

You have assumed a lot in the above post. The only crime I hold UTD accountable for is that they have allowed such bizarre misconceptions to go unaddressed on various internet forums. They actually sit back read this particular forum and laugh at such posts instead of coming out and addressing them. I myself have been a victim of a lot of this mind boggling BS and that is something I will be addressing in my other blog, "My Journey into UTD Ratio Deco."

For example, I went into my UTD course thinking that my instructor will give me a lecture on how evil dive computers are. Instead my instructor told me that he is totally fine with me using a computer even during UTD training dives. WHOAAA!!! There are some mainstream PSAI and TDI instructors who would not let you use a dive computer in class and if I remember correctly, Steve Lewis is one of them and he is quite far removed from GUE/UTD. My UTD instructor is saying, "ya go ahead and wear one!"

Even while using a computer, some folks may prefer standard gases over best mixes. Just sayin.
 
@tbone1004

Ratio Deco is not a requirement in UTD courses. It IS taught, along with the limitations (standard gases being one of those) but so is using a computer and software for cutting tables based on a team decided ascent profile (ie GF or VPM or whatever is deemed suitable)

NO UTD diver that I know uses only RD for their diving, I am sure they exist but EVERY dive I have been on with UTD divers there has been a SW on the wrist.

Whether or not there is any value in using RD in any context has been hashed out in multiple threads but as far as a non-standard gas dive (the OP of this thread) goes, nobody would be using it.
 
I think you caught Tom in a bad mood......and not suprising John is there whenever the 3 letters are mentioned. I have no stories or anidotes as my remote travel destinations either aren’t very remote or I dive what they have. There are usually lots of dive options if the “standard” gases aren’t available. Fiscally, with helium, I really appreciate diving what I have in my tanks and heaven forbid, seeing how close my shearwater follows my dive plan......
 
Don't assume that just because you're a "UTD diver" you can't dive non-standard gases. You're a diver first, apply your knowledge of decompression accordingly. Dive your desired PPO2 at the target average depth and keep your equivalent narcotic depth to 100’/30m or less. Don't ever dive deep air.

If you'e taking a UTD class, you're going to be diving standard gases.
 
To word it better, I am more concerned about places where Helium is not available and you end up doing air or Nitrox to 160. It won’t be the minor deviation from standard gases that is mentioned above. Of course you can manage the dive and compromise brain function like every one else but GUE and UTD have been diving in previously unexplored places and due to some magic they always have standard mixes (i.e Helium) at those locations.
 
Hmm, if you can’t keep END less than 100’ and cant keep an average PPO2 less than or equal 1.2, maximum 1.4 (deco 1.6), then I wouldn’t do the dive and I would never advocate doing so. Go reef diving, plenty to see :)
 
To word it better, I am more concerned about places where Helium is not available and you end up doing air or Nitrox to 160. It won’t be the minor deviation from standard gases that is mentioned above. Of course you can manage the dive and compromise brain function like every one else but GUE and UTD have been diving in previously unexplored places and due to some magic they always have standard mixes (i.e Helium) at those locations.
That magic is called planning and networking. It takes money to get helium to remote places, but it can be done.

Otherwise, option #1 is in effect: Don’t dive.
 
@CAPTAIN SINBAD would it not be better for them as an agency to come out and correct the information that is taken from their leaders youtube channel to correct any errors? He seemed very clear that RD was how UTD trained their divers.

Either way, what @PfcAJ said is best, figure it out if you believe in why standard gases are used and the benefit that they have for you, or don't dive.
 
https://www.shearwater.com/products/swift/
http://cavediveflorida.com/Rum_House.htm

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