DIR- Generic Tdi Normoxic trimix or CCR?

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SDI/TDI standards are tried and tested by technical divers around the world.
Just like the mainstream dive algorithms.
True enough. But they are not the DiR standards. Which is what this forum is for. So move along please.
 
What if your local helium supplier said they were no longer going to fill OC cylinders and would only fill for CCR? That’s the reality with some shops here in the US. In other places, there isn’t any helium to be had.

The reason GUE advocates helium sooner rather than later is because they feel that for dives in challenging conditions, helium makes the dive safer. The standard gas for dives between 30-45metrs is 21/35. The assessment of whether it is safer to dive with helium in those depth ranges is agnostic of cost. They believe it is safer. Full stop.

The ever increasing cost of helium or the lack of availability of helium doesn’t change the fact that GUE think that 21/35 is the preferred gas for those ranges. Whether or not it is realistic or feasible to use 21/35 depending on your location is a different discussion altogether.
 
$100 vs $10 and I'm the zealot?

Pragmatism has to make an appearance at some point. Or when you simply won't be able to get an open circuit fill -- unless it's for bailout use.
This is the pragmatic approach for me right now. I'm not limited by availability and, for $100 more, I can do dives to 170ft using the exact same techniques I've been using for the last 7 years and have built up experience and muscle memory with. This is a cost increase that is acceptable to me considering the level of confidence and comfort it gives me on my dives.

What is not pragmatic for me is spending $10-15k on rebreather equipment and training and going through the entire process of building experience and confidence on the unit before I can do those dives.
This is ignoring my risk aversion that makes CCR a non-starter now - likely even more so in the future as my family grows.
 
The reason GUE advocates helium sooner rather than later is because they feel that for dives in challenging conditions, helium makes the dive safer. The standard gas for dives between 30-45metrs is 21/35. The assessment of whether it is safer to dive with helium in those depth ranges is agnostic of cost. They believe it is safer. Full stop.
And the science backs them on this (interestingly they had enough experience to figure this out prior to the scientific studies coming out).
The ever increasing cost of helium or the lack of availability of helium doesn’t change the fact that GUE think that 21/35 is the preferred gas for those ranges. Whether or not it is realistic or feasible to use 21/35 depending on your location is a different discussion altogether.
I don't think it can be separated all together. Ideally, GUE training would be ubiquitous. Obviously, GUE would never have the same number of instructors as say SSI or PADI (the QC would be difficult to manage). However, for someone to follow the GUE path in parts of the world where there are GUE instructors, the availability and cost of helium is an issue. And it is only getting worse.

Just as T2 is no longer a requirement for CCR1, T1 may need to follow by the way side as well, but something needs to be put in its place. To go straight from a fundies tech pass to CCR without any bottle handling isn't something that I certainly wouldn't recommend.

Only time will tell. Hopefully a new source of cheap helium would be found and you can thumb your nose at us. I'd like that as that means I've got cheaper and more readily available helium. I just don't expect it.
 
Whether or not it is realistic or feasible to use 21/35 depending on your location is a different discussion altogether.
Other posters have brought that up. Will they grant dispensations to use other mixes if enough helium can’t be had? That will be interesting to see if they unbend a bit due to circumstances or not.
 
Zealotry is never a good method of persuasion.

I'm confused who you think GUE is trying to persuade.

What if your local helium supplier said they were no longer going to fill OC cylinders and would only fill for CCR? That’s the reality with some shops here in the US. In other places, there isn’t any helium to be had.

Get your own tank own he.

Other posters have brought that up. Will they grant dispensations to use other mixes if enough helium can’t be had? That will be interesting to see if they unbend a bit due to circumstances or not.

Why would you alter the standards to do a dive if you don't have the gas required to do the dive safely. If you don't have the gases to do it safely, either figure out the logistics or don't do the dive.
 
Why would you alter the standards to do a dive if you don't have the gas required to do the dive safely. If you don't have the gases to do it safely, either figure out the logistics or don't do the dive.
So this appears to be the crux of what this thread has turned into- either spend the money on the scarce helium to do it the DIR/ GUE way or figure out other logistics if you want to dive and therefore probably step outside the bounds of what is considered "correct". As @Wibble said, GUE has done much for safety and standards in our sport but needs to be able to adapt to changing variables such as access to/ availability of helium.
 
Get your own tank own he.
Getting your own He doesn’t help if none is available.
Why would you alter the standards to do a dive if you don't have the gas required to do the dive safely. If you don't have the gases to do it safely, either figure out the logistics or don't do the dive.

OC Trimix is going the way of the dodo.

Is it pearl-clutching time for GUE divers if they only have enough helium to do 25%-30% instead of 35% for a shallower dive, say 130ft?

“Figure out the logistics” doesn’t do a damned thing if you can’t get any helium at all or not quite enough. That’s what we’re trying to convey. Is GUE going to keep beating the drum of standard mixes *at all costs* if divers can’t get enough helium? You want to do a 110ft dive. There’s no helium. Do you do it on nitrox or not at all?
 
Getting your own He doesn’t help if none is available.


OC Trimix is going the way of the dodo.

Is it pearl-clutching time for GUE divers if they only have enough helium to do 25%-30% instead of 35% for a shallower dive, say 130ft?

“Figure out the logistics” doesn’t do a damned thing if you can’t get any helium at all or not quite enough. That’s what we’re trying to convey. Is GUE going to keep beating the drum of standard mixes *at all costs* if divers can’t get enough helium? You want to do a 110ft dive. There’s no helium. Do you do it on nitrox or not at all?
What other component of scuba should you forgo if it’s not available?

Getting Sensors was a problem not too long ago. Push em anyways? Reg parts occasionally become unavailable. Just dive with small leaks? Issues with finding aluminum tanks. Steel stages? Sorb can be a logistical problem. Push the scrubbers?

Technical diving requires certain equipment. If you can’t get it, just…. Don’t? It’s scuba diving, it’s not like some ultra critical thing that HAS to be done. Sheesh.
 
I wish we could go back to having to admit people into the DIR forums. It's becoming people that hate GUE and DIR commenting on sh-t they don't actually know about or have experience with. Or the bot boy from Alaska that thankfully everyone's figured out to just ignore.
I'm Heltirox certified for many years and pretty much dive helium every dive, I dive CCR mostly (not even a GUE approved one), yet I take Tech 1 in Mexico in about 4 weeks. Maybe I'm a fu--tard that likes to spend too much money on helium. Or maybe my goal is to be as proficient as possible diving OC trimix so that when my rebreather sh-ts the bed and I'm suddenly an OC trimix diver, I'm not stressed out sucking down gas or screw up a gas switch and start doing the convulsion dance at 150 feet.
And even nuttier, I have no plan in ever taking any CCR trimix classes.
 
https://www.shearwater.com/products/perdix-ai/
http://cavediveflorida.com/Rum_House.htm

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