Nitrox above 40%

[Peter M]

most manufactures tell you not to use your regulator above 40% nitrox, so do you just clean one or do you buy one for this purpose when using say 50%?
Not wanting to spontaneously combust on deco!

[Reikimaster]

either or, depends whch regs you have.

Apeks to O2 compatible service kits for most of their regs so a service stating you want them O2 clean is an option.

not sure about other makes

[Sean]

Maybe a dumb question but what would happen if you used normal regs IE not O2 clean.

[GLOC]

Anything upto this...

http://www.yorkshire-divers.com/foru...318-post1.html

[Sean]

Originally Posted by GLOC

Anything Upton this...

http://www.yorkshire-divers.com/foru...318-post1.html

OK I understand why tanks should be O2 clean with the risk's involved when filling but when its in the tanks what's the issue breathing it from any reg when on deco stops. I'm sure the mask's used in hospital and on ambulances are not O2 clean

Sean

[NeilP]

As far as I understand, you CAN use out of the box regs for higher percentage o2.

EDIT: NOt the Titanium jobbies though.

[nigelH]

Originally Posted by Sean

I'm sure the mask's used in hospital and on ambulances are not O2 clean

Correct. But it's not the mask bit you clean. Its the bit under pressure. High pressure oxygen, or just rich mix, even at the 10bar interstage pressure can be nasty as most things burn well in O2.

The best example is taking a rich source of oxygen (Saltpetre) and adding a catalyst to get the oxygen out fast (sulphur).
This is what converts those charcoal things you can never get to light on your barbie into the gunpowder Guy Fawkes tried to blow up Parliament with.

Oxygen is not your friend.

[Sean]

Just to summaries for me then, providing your tanks are O2 clean as mine are there are no requirements for a certain or even O2 reg when using a mix over 40% or am I still being thick

[nickb]

For equipment to be in 'Oxygen Service', you need to satisfy 2 criteria.

All parts that come into contact with the gas need to be 'Oxygen Compatible' AND 'Oxygen Clean'.

The first of those means that the materials used need to be stable in an oxygen-rich environment.

The second bit means that all the components are cleaned to a standard that reduces any hydrocarbon impurites to a negligible level.

AFAIK, all the parts in an Apeks first-stage service kit are 'Oxygen Compatible' with the exception of the little disc-shaped filter that goes into the A-clamp (but none of us are using those are we?). I'm pretty sure that they're also 'Oxygen Clean' as supplied, but unless your hands, work-surfaces and tools are also meticulously clean, they won't stay that way whilst you install them.

Some regs cannot be put into oxygen-service e.g. fancy titanium regs. So, no matter how oxygen-clean these things might be, they should never be used with high nitrox mixes.

[Lou]

The bit wot always confoozes me....is that little o-ring and greasy finger-print bit between your tank and your reg. Maybe even a bit of sandwich in there Why is that bit not important?