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View Full Version : Why are titanium 1st stages and Nitrox a no no?



Paco II
07-10-2007, 13:59
So my title is not entirely accurate, I know. However I have read how some titanium 1st stages are not recommended for use with Nitrox, or for Nitrox only and not switching it up with air. Can someone point me to a site with some good info on that, or post that info here?

Wolfie2012
07-10-2007, 14:50
The reason that the titanium and nitrox incompatibility issues came into place is because titanium as a metal is highly flamable (think similar to those magnesium camping firestarters, moreso in powdered form). As the oxygen content of the gas is increased, it increases the chance for fire.
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<DIV>The reality is that most titanium regulators are rated for recreational nitrox (up to 40%). The manufacturer will label those regulators as such.</DIV>
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<DIV>Titanium is not recommended for nitrox mixes higher than that, as simply a safety issue.</DIV>

Paco II
07-10-2007, 14:57
Cool. So in regards to something like the Atomic T1, where they recommend using it for air only or nitrox only, what's that about?

Wolfie2012
07-10-2007, 15:27
In my opinion they're being overly cautious, and it is a decision you as a responsible diver should be able to make. For recreational nitrox (up to 40%)it shouldn't be an issue. Others may feel differently.Of course you should always pay attention to how well a shop maintains their compressor to be sure you're not getting bad air anyway. To be fair, this is what their FAQ says off their website:
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Can I switch back and forth between air and Nitrox?
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No, we do not recommend it. There are different cleaning and purity standards for air and Nitrox. Using standard compressed air with your regulator could introduce dirt or hydrocarbon contaminants into your regulator that could possibly initiate an ignition (fire) in your system. Oxygen enriched mixes can be highly combustible under the right conditions. It is always better to be safe then sorry.[/list]</DIV>

Dustinh
07-10-2007, 15:57
From what I understand, as long as you're getting your reg serviced at regular intervals, and get your air (and nitrox) fills from reputable places, contamination should not be too big an issue, especially if it's occasional nitrox use, say for a day or two on a multi-dive day vacation.

bobbin-along
07-10-2007, 20:00
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In reference to the Gas switching comment on their site:
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Can I switch back and forth between air and Nitrox</DIV>
<DIV>No, we do not recommend it. There are different cleaning and purity standards for air and Nitrox. Using standard compressed air with your regulator could introduce dirt or hydrocarbon contaminants into your regulator that could possibly initiate an ignition (fire) in your system. Oxygen enriched mixes can be highly combustible under the right conditions. It is always better to be safe then sorry. </DIV>
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<DIV>Wow, that's a bit picky for recreational nitrox and a regulator. If they are worried about over 40% O2 compliant reg, they should stipulate that, not just the generic term "nitrox". While I understand the argument for nitrox that is partial pressure blended within a CYLINDER, there really shouldn't be any problem with swapping 21% nitrox or 36% nitrox through a regulator.Obviously lawyers must have had some input in this FAQ.</DIV>
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<DIV>Does anyone have any solid fact about the dangers of sub 40% O2 gas switching in a regulator to back up the "better safe than sorry" comment?</DIV></DIV>

Wolfie2012
07-10-2007, 23:48
Obviously lawyers must have had some input in this FAQ.
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<DIV>Does anyone have any solid fact about the dangers of sub 40% O2 gas switching in a regulator to back up the "better safe than sorry" comment?</DIV></DIV>
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<DIV>I agree, that FAQ definitely smells of lawyer. I can't find any evidence of statistical research into the dangers of &lt;40% gas switching. Until I do, I don't put any stock into their statement, and I can't possibly see how anyone can back that statement up. To me it's like somebody saying "Don't dive because you'll be swallowed wholeby a blue whale. Better safe than sorry." In my opinion, it's ridiculous. ;)</DIV>

Dive-aholic
07-11-2007, 02:11
I heard that what happened was in a laboratory setting under perfect conditions while applying pressurized oxygen to a titanium regulator there was an explosion. I've never heard of this happening in a regular day to day setting.
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<DIV>As for switching back and forth between nitrox and air - there's not problem that I've ever heard or read with this in regards to regulators. With cylinders it is a problem. Regulators will not see a greater than 40% mix are okay. The issue of hydrocarbons building up on the reg isn't going to affect the reg because it won't ever see a higher mix of oxygen. Hydrocarbons are only an issue with high percentages of oxygen.</DIV>

Blindref757
07-11-2007, 07:53
My Mares BC recommends an O2 scrub if used with recreational nitrox! You guys are correct...this is just lawyer terrorization!!!

CompuDude
07-11-2007, 19:57
Yup, don't sweat it. There would be actual reports of explosions if this was a problem, as people have been using regs with 40% for a while now without worrying about anything. Anything higher, and it's time for different regs.