Oxigen Concentrator to a tank

[Andrius Be]

Anyone using oxigen concentrators commercialy available to fill O² tanks with oxigen?

 

[Tracy]

You need some guide definitions before embarking down this route. The main route path is
Medical Oxygen, Aviators Oxygen and Divers Oxygen the three distinct classifications for Breathing Oxygen.

There are also other sub classifications of Breathing Oxygen by application such as for Medical Hyperbaric Chambers. Diving Chambers under PVHO for example Pressure Vessel Human Occupancy and for Saturation Chambers and Diving Bells with specifications that come under a number of classification authorities sure as Lloyds Rules and Regulations for Submersibles and Diving Systems Det Norsk Veritas DNV etc

Now by contrast the off the scale suggestion here in the forum is way under the standards required and the suggestion of using what is basically an ambulatory oxygen generator that at best (when new) will provide around 90% to 93% Oxygen in Argon and that will over time degrade further down to the 80% range is IMHO frankly ill advised..

You can also see the consideration suggested earlier that in a closed loop when 20% by volume of the breathing bag would be by definition become hypoxic in closed circuit and frankly foolish in open circuit.

Breathing Ambulatory Oxygen sitting in bed at a ripe old age while waiting to meet your maker is one thing.

Hooking it up to a scuba tank for a cheap fill on the side for you and your mates is by contrast Darwinian.

Others my disagree.

Or, when new they generate around 95% o2 and when they get below 90%, the booster sensors won't allow it to turn on and fill a tank.
ASo not perfect at all, but 90% is a lot different than 80% and for oc deco will certainly work as not everywhere has o2 readily available.

 

[grantmac]

Can you not just get them serviced once the oxygen content drops below whichever level you determine is appropriate for your use? It seems like there is a pretty good infrastructure in place for these things at least in areas with an aging population.

 

[iain/hsm]

Or, when new they generate around 95% o2 and when they get below 90%, the booster sensors won't allow it to turn on and fill a tank.

That's reassuring, Not.
Except first you need to define the accuracy of your statement for this 90% cut out figure you claim.

I don’t want to get into a great fight here as I really don’t care but you have assumed as others that this 90% figure is accurate and correct however the means of verification needs to be understood fully first and in much greater detail before you can assume that this shut off devise is suitable for a divers application.
Look some old grannie out back on the porch breathing it up a through a nasal cannula is not going to be affected in any way as supplemental oxygen in practice is well below the level of oxygen your quoting.

In practice application wise the delivery of so called oxygen is 28 to 45%
But the devil is in the detail and the method of analysis for these generators is by zirconia sensors an odd choice to make for the application but a cheap one.

Zirconia signal resolution for oxygen concentrations or accuracy is hugely reduced above that of 21% Air. Albeit in the 1ppm to 10ppm they work fine with sensor signal of around 100 to 200 mV but with higher oxygen concentrations it drops off a cliff with a wild ass guess of zero to Minus -50mV for the standard NATO mixes range of 60/40, 40/60 and 32.5% making it as suitable as using a canary bird in a cage.

In order to make these generators as a cheap disposable product for granny then you need to use a cheap zirconia sensor I get it.

But for diving do you really want to advocate the " Do what like and feel lucky" approach as long as it’s within your financial budget I guess. Just a thought. Iain

 

[iain/hsm]

Can you not just get them serviced once the oxygen content drops below whichever level you determine is appropriate for your use? It seems like there is a pretty good infrastructure in place for these things at least in areas with an aging population.

Another difficult assumption.
And with respect on par with misappropriating Chinese two stage air gun compressors for scuba tank breathing air filling or the safety of using a full face mask with snorkel attached and no oral nasal protection or one way exhalation device.

Now while it may help in terminating an aging diving population and the beach snorkeler's.
As for servicing you need also to define servicing and the details required to make an informed choice you clearly don’t yet understand.

The assumption that the Chinese synthetic zeolite chemical generators used for these products can be serviced is one thing however being suitable for a diving application is quite another.

Ambulatory oxygen by generator is just a point of use product for a marginal elevated oxygen concentration in ambient air atmospheric conditions. Ask grannie if they are any good as I will only make it worse.

 

[Tracy]

That's reassuring, Not.
Except first you need to define the accuracy of your statement for this 90% cut out figure you claim.

I don’t want to get into a great fight here as I really don’t care but you have assumed as others that this 90% figure is accurate and correct however the means of verification needs to be understood fully first and in much greater detail before you can assume that this shut off devise is suitable for a divers application.
Look some old grannie out back on the porch breathing it up a through a nasal cannula is not going to be affected in any way as supplemental oxygen in practice is well below the level of oxygen your quoting.

In practice application wise the delivery of so called oxygen is 28 to 45%
But the devil is in the detail and the method of analysis for these generators is by zirconia sensors an odd choice to make for the application but a cheap one.

Zirconia signal resolution for oxygen concentrations or accuracy is hugely reduced above that of 21% Air. Albeit in the 1ppm to 10ppm they work fine with sensor signal of around 100 to 200 mV but with higher oxygen concentrations it drops off a cliff with a wild ass guess of zero to Minus -50mV for the standard NATO mixes range of 60/40, 40/60 and 32.5% making it as suitable as using a canary bird in a cage.

In order to make these generators as a cheap disposable product for granny then you need to use a cheap zirconia sensor I get it.

But for diving do you really want to advocate the " Do what like and feel lucky" approach as long as it’s within your financial budget I guess. Just a thought. Iain

so, our regular old oxygen analyzers that we use every day to verify tank contents are fine to use. But because this oxygen came from a different source, we can't trust the accuracy anymore. That makes sense.
I understand that the internal sensor of the booster may be complete garbage, but the gas still gets analyzed in the tank prior to breathing it.
I have actually had the output analyzed. On my last sample, there was 95%oxygen, about 4.5% argon, and lots of trace gases making the last .5%.
I'm not saying that it is something everybody should do, or even anybody should do. My statement was that it can be done, I have done it, and it works. It isn't perfect, but in some places, it is a way to make something with nothing.

 

[iain/hsm]

so, our regular old oxygen analyzers that we use every day to verify tank contents are fine to use. But because this oxygen came from a different source, we can't trust the accuracy anymore. That makes sense.
I understand that the internal sensor of the booster may be complete garbage, but the gas still gets analyzed in the tank prior to breathing it.
I have actually had the output analyzed. On my last sample, there was 95%oxygen, about 4.5% argon, and lots of trace gases making the last .5%.
I'm not saying that it is something everybody should do, or even anybody should do. My statement was that it can be done, I have done it, and it works. It isn't perfect, but in some places, it is a way to make something with nothing.

No don't be misleading here.

"Our regular old oxygen analyser that we use every day are fine to use"

As you put it as old these I've assumed are basically a galvanic fuel cell. A chemical battery that runs down over time needing replacement.

This is no where near the same as the zirconia sensor used in these Chinese generators.
And again as you put it earlier

"When they get below 90%, the booster sensors won't allow it to turn on and fill a tank".

And we are back to the original problem of accuracy dependability and reliability against a wild ass guess with a poor choice of analysis component for the application together with an even poorer quality choice of generator chemical.

 

[Tracy]

No don't be misleading here.

"Our regular old oxygen analyser that we use every day are fine to use"

As you put it as old these I've assumed are basically a galvanic fuel cell. A chemical battery that runs down over time needing replacement.

This is no where near the same as the zirconia sensor used in these Chinese generators.
And again as you put it earlier

"When they get below 90%, the booster sensors won't allow it to turn on and fill a tank".

And we are back to the original problem of accuracy dependability and reliability against a wild ass guess with a poor choice of analysis component for the application together with an even poorer quality choice of generator chemical.

I didn't say they were the same, I said it gets analyzed by one of those prior to breathing. The one in the booster is just a failsafe built in to the booster. It's accuracy is of little concern as it is merely a go/no go switch to turn the booster on.

 

[TecSideMount0491]

Why do I get the feeling here that having a dense vocabulary equates to the facade of being the gift to mankind? There are those that talk about it and there are those that do it and live to tell the tale. Where would we be without experimentation? It’s important to note that those embarking on self experimentation often also take full responsibility of their own actions.

 

[GiraffeMarineSalvage]

so, our regular old oxygen analyzers that we use every day to verify tank contents are fine to use. But because this oxygen came from a different source, we can't trust the accuracy anymore. That makes sense.
I understand that the internal sensor of the booster may be complete garbage, but the gas still gets analyzed in the tank prior to breathing it.
I have actually had the output analyzed. On my last sample, there was 95%oxygen, about 4.5% argon, and lots of trace gases making the last .5%.
I'm not saying that it is something everybody should do, or even anybody should do. My statement was that it can be done, I have done it, and it works. It isn't perfect, but in some places, it is a way to make something with nothing.

Thank you very much Tracy,
I've spent a lot of time thinking through best options for EAN50+ and "pure-ish" O2 when my boat is in very remote locations and your detailed knowledge on how to practically navigate that is very helpful...