Accelerated decompression on an argon mix?

[PfcAJ]

I know it was, and so were better practices

Like proper markings of bottles, 100% as a deco gas, extended time on helium gasses, etc etc.

 

[Slamfire]

I know it was, and so were better practices

Like proper markings of bottles, 100% as a deco gas, extended time on helium gasses, etc etc.

The thread is about deco on Ar mix. It's not about debating what are the best practices for cylinder markings. Cylinder markings are inconsequential to human metabolism. Best practices according to GUE, at least when referring to cylinder markings, are not the same as best practices according to the rest of the world. Let's keep the discussion on topic and avoid bringing in inconsequential biased pseudo proofs.

 

[rjack321]

Best practices according to GUE, at least when referring to cylinder markings, are not the same as best practices according to the rest of the world.

Actually they pretty much are. Feel free at ask how 90%+ of the technical divers mark their gas on any of the actual deco diving boards (sorry SB doesn't count unless your in T2T).

MOD numbers in either ft or m on the side
analysis tape on the crown

no more "cylinder wraps", "decompression mix" etc

The fact that the book was written almost 10 years ago and ultizes a variety of practices which have since fallen out of favor as either, ineffective, inefficient, or even actually dangerous is telling. If the actual diving practices are that far out of date, the credibility of the physiology discussed therein is comparatively dubious. And surprise surprise, AJ was able to easily demonstrate that in Buhlmann decoplanner. Its not so easy to demonstrate in the V-planner software. Of course both of those models are "wrong" too, but they are widely accepted as not uselessly wrong like a reg cover, color coded deco cylinders, or that all the helium is already offgassed by 30ft.

 

[SuPrBuGmAn]

My 20ft bottle just says...

FUMYO2

I LOL everytime I get back to it. :/

 

[H2O 70]

I've been reading Deco for Divers by Mark Powell. I finished the Trimix chapter last night and that got me thinking. Helium on gasses faster and off gasses faster than Nitrogen. So a Trimix dive profile needs to take into consideration two inert gasses. If you dive profile has some deeper stops where it makes sense to switch to EAN50, why not do a 50% Heliox?

 

[Slamfire]

If the actual diving practices are that far out of date, the credibility of the physiology discussed therein is comparatively dubious.

No, sir, you cannot make that connection. It is possible to have solid science behind a statement while at the same time have sloppy or even deplorable diving practices. I am not defending the guy's claim that you're He free by the time you hit 30'. But saying that he's a sloppy diver does not disprove his science.

AJ proved it easily in a more direct and valid way. Great. Why not start there and avoid comments on regulator colors? You guys are superbly trained. You have the tools and the knowledge. Can't you use all that training to first focus on addressing the issue directly? Why create noise on contentious debatable points that don't add anything useful to the discussion? You have the potential to add so much to the board. If you keep it positive instead of pointing fingers and having a chuckle every time you spot a stroke, you're going to help the DIR cause in a far more efficient way instead of hurting it.

 

[ucfdiver]

I've been reading Deco for Divers by Mark Powell. I finished the Trimix chapter last night and that got me thinking. Helium on gasses faster and off gasses faster than Nitrogen. So a Trimix dive profile needs to take into consideration two inert gasses. If you dive profile has some deeper stops where it makes sense to switch to EAN50, why not do a 50% Heliox?

Keep in mind, there's no sudden point where off gassing starts and on gassing stops. ZHL16B is easiest to explain because it has table values for He/N2, and you use proportions of the breathing mix to figure out how fast the tissue off gasses overall. If you get on a heavy He mix, you might be saturating slow tissues that were not previously saturated, even though it might speed up the off gassing of faster tissues.

That being said, there's clear benefit to using helium deco mixes, it's just not the end-all.

 

[roakey]

Over a decade ago Hamilton came to speak at the first &#8211; and only &#8211; DAN conference in Colorado Springs. He was asked about Argon mixtures and, while looking at someone in the audience who he obviously knew well and for quite some time (I don&#8217;t remember his name), he asked rhetorically &#8220;<name>, how often did we get bent when we were trying Argox? <long pause for effect> Oh, that&#8217;s right, 100% of the time!&#8221;

Just an interesting story&#8230;

Roak