Oxygen generator - generating higher PSI for storage.

[NAM001]

My o2 meter shows 96%. accuracy is always at ??? on te extreem ends of any meter. the concentrator sould be putting out 22 parts of the 100 of air. 21 o2 and <1 argon. which is 95.5 02 and tha ballence if argon wouls be 4.5%.

Is itt safe to assume that we can deal with ppn2 of about 4.0 pretty well and that if argon is 2.33 times as narcotic as n2 then we should be able to handle argon at ppar of 1.7 and that 1.7/.04 ahould give us the mod for argon of 38 atm one being surfce and the other 37 being 37*33 or over 1000 ft depth. With all the talk in other threads and some concern for the argon issue my mod argon guess has to be wrong, or a non issue. I ahve been using concentrator o2 in blending nitrox nearly forever. Using to 130 ft , mostly < 80 though. I have notived no issues but will admit the user is usually that last to know when narcosis is involved.

 

[lonebrave]

Note: I'm not a rebreather diver. I have not had any formal rebreather training. I have read some information online and am reading through Mastering Rebreathers, 2nd ed, by Bozanic. I don't claim to know everything.

Ian, I wasn't referring to you, sorry you got that impression. Again as I'm primarily a RB diver (99%) I tend to look at things a bit more critically.

More critically than what? than you did before you were a RB diver? Not really sure what difference that makes. I would have thought that actually calculating out the PPAr math would be considered a detailed look at the situation.

I actually looked into a concentrator years ago but found the best would only produce about 93% O2 with the balance being Ar. ( actually a quick look today and the vast majority still only claim 93%......so 96% maybe a bit.........optimistic).

Or it might be completely accurate. I haven't, and am assuming you haven't as well, tested particular system.

As you know using a gas that has any type of "contamination" in it in a rebreather is a death wish.
To explain for those that don't know much about rebreathers:
Once a RB diver reaches the depth they want, no further dilutent is added, more or less stays constant (except what is entering the "tissue compartments". The only thing that gets added is O2. Now if your O2 is contaminated, that also gets added. So the average O2 consumption is about 1L/min (actually a bit less, but this makes the math a bit easier). So if you have 4% of a contaminent you have 960 ml O2 and 40 ml of contaminent added. Now you metabloize the O2 but leave the contaminate, so the next minute you've added the mext 960 ml and the 40 ml, but now there is 80 ml of the contaminate in the loop. Now this happens every minute.
It's not uncommon to do 2-4+ dives on a RB, so I'll let someone else finish that math. Figure a loop volume of 10L.

Doesn't the loop get flushed between dives? I would think that multiple dives on a single fill in this situation would actually be cause for less Ar buildup in the loop.

Now there are ways that it can be done, freq. dilutent flushes, but that's not the point of a RB.
And yes it's probably ok to breathe some, I'm sure people do it all the time, but it's not for me. Maybe my personal standards are a bit strict, but they work for me.
Later,
John

I always thought it was 'diluent', not 'dilutent', but I'm not a RB diver.

 

[manni-yunk]

Ian, I wasn't referring to you, sorry you got that impression. Again as I'm primarily a RB diver (99%) I tend to look at things a bit more critically. I actually looked into a concentrator years ago but found the best would only produce about 93% O2 with the balance being Ar. ( actually a quick look today and the vast majority still only claim 93%......so 96% maybe a bit.........optimistic).
As you know using a gas that has any type of "contamination" in it in a rebreather is a death wish.
To explain for those that don't know much about rebreathers:
Once a RB diver reaches the depth they want, no further dilutent is added, more or less stays constant (except what is entering the "tissue compartments". The only thing that gets added is O2. Now if your O2 is contaminated, that also gets added. So the average O2 consumption is about 1L/min (actually a bit less, but this makes the math a bit easier). So if you have 4% of a contaminent you have 960 ml O2 and 40 ml of contaminent added. Now you metabloize the O2 but leave the contaminate, so the next minute you've added the mext 960 ml and the 40 ml, but now there is 80 ml of the contaminate in the loop. Now this happens every minute.
It's not uncommon to do 2-4+ dives on a RB, so I'll let someone else finish that math. Figure a loop volume of 10L.
Now there are ways that it can be done, freq. dilutent flushes, but that's not the point of a RB.
And yes it's probably ok to breathe some, I'm sure people do it all the time, but it's not for me. Maybe my personal standards are a bit strict, but they work for me.
Later,
John

Perhaps there is more risk involved with a small percentage of argon for a RB diver vs OC..I realy dont know. I know rebreather divers fill their dilluent tanks from a compressor and most compressors regularly fill tanks with 1% argon, and Ive never heard of a problem. But - thats not what you incinuated in your first post in this thread. You clearly said - look up the effects of argon in "diving situations". Which, as we have appropriately pointed out - are negligible in small concentrations for most divers since most divers in diving situations are on open circuit.