Nitrox and titanium

[Bigd2722]

Met an instructor today who insists that nitrox is not allowable for titanium regs. Hell, when I had a titanium reg, I never dove anything except nitrox. You?

 

[diversteve]

It's the percentage. Atomic's Ti models for example are certified to 40%. So most conventional mixes are fine.

Show him this: http://www.atomicaquatics.com/nitrox.html

 

[NAM001]

From what i have read itis my opinion that that is garbage. I read and article about o2 and titanium and the hazzard existed with o2 at 40k psi and above. I imagine if you had fine titanium shavings in the reg that would significantly lower that number. Its like steel,,,, it does not burn,,,, but you can light it right up with a match if its steel wool. Lots of mixed opinion on this topic. of course you have to have fuel o2 and HEAT to get a fire. There are the threads with posters that are very much anti nitrox because "no scuba regulator is designed for O2 use" The position is understandable because of the contorted air paths through the reg and the posisbility of anabolic heating. I think that is the right word. Even that is a very small issue with the minimal gas flow needed to equalize the reg with tank pressure. I am more from the camp of not worrying about the 1 in ten million regs with titanium shavings in them being hit with 4500 ppsi O2 while supporting a 20 ft secondary hose. Those in the rec world will never have to be concerned with this and the tekies just know how to deal with O2 and have dedicated regs for O2 use. If anything it would be PURE O2 in a titanium reg and that only applied to regs certain parts of titanium.

 

[WarrenZ]

At recreational level mixes some manufactures say it is ok however I have seen an demonstration of a titanium reg sparking during disassembly that made me think twice about having a titanium reg for any raised O2 gases.

 

[BoltSnap]

The Titanium regulator manufacturers I know (Atomic, SP) say that their Ti regs are good up to 40% Nitrox mix no problem. I vaguely remember an issue with an Atomic Ti regulator in the late 90's when it was exposed to circa 100% O2 but I can't remember the details.

 

[eelnoraa]

Not technical answer but my own experience. I have been using Atomic Ti first stage with 32% for 3 years, hundreds of dives an without any issues. This Ti reg is before the latest Atomic upgrade for recreation O2 compatibility.

 

[laurin]

According to this article:
http://c.ymcdn.com/sites/membership.../safety_docs/titanium_hbo_fire_risk_(hink.pdf

..."It has been reported that an oxygen partial pressure of 25 ATA (2514 kPa) was required to ignite and burn a fresh titanium surface at room temperature during static conditions (1)." You get way past that ppO2 even with air in a 200 bar tank, so pressurizing a reg (not a static condition!) on a hot day you're essentially relying on the titanium oxide layer inside the reg being unscratched.

This is probably not a huge concern, so it boils down to making a judgment call between the high impact / low probability risk of oxygen fire and the rather meager benefits of titanium regs.

 

[BoltSnap]

This is probably not a huge concern, so it boils down to making a judgment call between the high impact / low probability risk of oxygen fire and the rather meager benefits of titanium regs.

And how many times has this ignition take place in the field again???