Are analog gauges nitrox compatible?

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Skinsfan1311

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This is probably a silly question. Obviously, I'm not nitrox-certified and I understand that people dive Nitrox, with computers. It's my understanding that many divers utilize an analog SPG, along with a wrist computer, and the computer must be Nitrox-compatible. What about an analog SPG? Thanks!
 
SPG measures pressure in the tank. It doesn't matter whether it is air or Nitrox. I guess that would make all SPG Nitrox compatible.

Maybe the reason you asked the question is that you are not clear on what it means when a computer is Nitrox compatible. I am not Nitrox certified so I will leave that explanation to some with more knowledge than I.
 
Here's the thing on that . . .

When you attach your 1st stage to the tank, air (21%) is occupying the interior volume of your hose.

When you open the valve, all you're doing is compressing the gas already in the hose.
The gas doesn't flow through on a continuous basis like it does your regulators.

Should be no issue.

the K
 
I just recently became Nitrox certified, so my explaination may be wrong.

But as far as I know, a nitrox compatible computer measures your ppO2, percent mix (i.e. 32% O2), along with some other factors.

The partial pressure is particularly important to monitor because as you go deeper you know that your ata increases. Well, with nitrox since there is a higher concentration of O2 you must be careful that the partial pressure does not exceed 1.4 (According to NAUI). If you exceed that partial pressure, you expose yourself to risks of oxygen toxicity which can lead to serve problems especially when you are relatively deep, lets say 80-100 fsw.

So having a computer that can accept a Nitrox mix will monitor your depth and ppO2 to ensure that you do not go too deep for your particular mixture of nitrox.

Hope this helps. If anyone who is more experienced in this realizes I have mistated please coorect me.

Rob
 
Skinsfan1311:
This is probably a silly question. Obviously, I'm not nitrox-certified and I understand that people dive Nitrox, with computers. It's my understanding that many divers utilize an analog SPG, along with a wrist computer, and the computer must be Nitrox-compatible. What about an analog SPG? Thanks!
When you hear about Nitrox compatible computers, this is refering to computers which can be set to various percentages of O2 and make bottom time calculations based on that, as well as tracking total O2 exposure. (You can actually use an air only computer to dive with Nitrox, but you don't get the benefit of additional bottom time that way.)
 
robbanks78:
I just recently became Nitrox certified, so my explaination may be wrong.

But as far as I know, a nitrox compatible computer measures your ppO2, percent mix (i.e. 32% O2), along with some other factors.

The partial pressure is particularly important to monitor because as you go deeper you know that your ata increases. Well, with nitrox since there is a higher concentration of O2 you must be careful that the partial pressure does not exceed 1.4 (According to NAUI). If you exceed that partial pressure, you expose yourself to risks of oxygen toxicity which can lead to serve problems especially when you are relatively deep, lets say 80-100 fsw.

So having a computer that can accept a Nitrox mix will monitor your depth and ppO2 to ensure that you do not go too deep for your particular mixture of nitrox.

Hope this helps. If anyone who is more experienced in this realizes I have mistated please coorect me.

Rob

Good that you did seem to get good training. I believe he is asking though as to whether the components of analog SPGs are compatible with the actual Nitrox mixes. He didn't know if they should be serviced to handle the higher oxygen content.

I for one agree that the hose is filled with normal air and you are just compressing the air column. There is going to be some mixing, but I can't see it being a problem nor have I heard of it being a problem. Nothing in the training, that I have had, talks to O2 cleaning your SPG setup or having a special one for any type of Nitrox diving. All it talks about is the actual regs.
 
Rob, your assessment is correct, with one exception.
The dive computer doesn't "monitor" the gas mix, it simply performs a programmed calculation based upon a nitrox percentage factor and a ppo2 factor input by the user.

Unless the computer is an air intergrated unit coupled to the 1st stage regulator by a hose, nitrox and higher O2 percentages are not factors.

Even if it were coupled by a hose, the passage of a higher percentage of O2 would be of a very little concern, if at all.

The same goes for the analog pressure gauge.

the K
 
Thanks everyone! I'm constantly amazed at the speed, and quality of the responses that I receive on this board. Thanks, again!
 
One last point, some old dive gear had gaskets and parts that would degrade or at least was design for air only and not tested with the newer Nitrox gasses when they came in. Most modern dive gear will specifically tell you in the specs if it is rated for oxygen rich Nitrox and if so to what percentage. Most modern gear can easily handle Nitrox up to 40% Oxygen

Some Scuba gear, regs, gauges etc. have special certifications for working with more than 50% Oxygen. Tech divers use pure Oxygen as a deco gas, and pure oxygen has applications in rebreathers (I think – not my certification or specialty). But pure oxygen requires very special gasket etc. and everything must be kept squeaky clean or it can catch fire That type of pure oxygen gear costs a bit more and is in another class by itself.
 

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