Pure O2 Handling?

[KentCe]

Now that I carry an O2 bottle on my back I would like to understand everything about handling/filling pure O2. I ordered the Oxygen Hacker and Booster books from AirSpeed Press. Any other good books to read? Classes to take? Useful websites?

Thanks, Kent

 

[canuckdiver]

I'm far from an expert, but I would think that a blending course from a tech agency would be a good start on getting practical experience with dealing with O2.

 

[caveseeker7]

Certainly the handling part should have been ... :upset:

One good thing to do with O2 other than using it in your rebreather is providing it. Take the DAN O2 Provider course http://www.diversalertnetwork.org/ The safe handling of O2 is part of it, as well as the medical aspects etc. . Training is usually done on an DAN O2 rig, but the RB will do in an emergency, or an O2 clean 2nd stage. Or better yet, OMS' O2 kit. just grab your tank and switch regs.
For a while they actually taught REMO (rebreather emergency medical oxygen) classes. Mini RB to extend the supply, but those are currently out of production. Takes the better part of a day, and should cost less than $100. Worth it.

 

[caveseeker7]

 

[padiscubapro]

KentCe once bubbled...
Now that I carry an O2 bottle on my back I would like to understand everything about handling/filling pure O2. I ordered the Oxygen Hacker and Booster books from AirSpeed Press. Any other good books to read? Classes to take? Useful websites?

Thanks, Kent

kent
Who are you taking your class with?? O2 handling should have been part of it.. (or at least a prerequisite)

I don't want to make this sound like an ANDI plug, but if you do have an ANDI facility near you I would look into their oxygen provider class, its considerable more involved than the Dan program, although the Dan program is much easier to find an instructor...

The typical ANDI oxygen provider clas takes 6-8 hrs of lecture and a few hours of hands on (as long as it takes to run the scenarios)... When I run the oxp class I charge $125 for 6 students, more if a smaller class... The typical dan class is 4 hours total (1 hour lecture 3, hours skills).. although I hear people do it shorter...

 

[KentCe]

To reply to the last two messages.

Filling O2 bottles was not part of my Inspiration class, nor my Nitrox class, nor Adv Nitrox class or even my DAN O2 class. I believe the only comment was "turn the valve sloooowwwwly" and not the low details why this is important.

Of course after posting my question my copy of "OXYGEN HACKER'S COMPANION" arrive which was exactly what I was looking for (including the reason for slow valve movement).

 

[padiscubapro]

KentCe once bubbled...
To reply to the last two messages.

Filling O2 bottles was not part of my Inspiration class, nor my Nitrox class, nor Adv Nitrox class or even my DAN O2 class. I believe the only comment was "turn the valve sloooowwwwly" and not the low details why this is important.

Of course after posting my question my copy of "OXYGEN HACKER'S COMPANION" arrive which was exactly what I was looking for (including the reason for slow valve movement).

WOW!

depending on the persons prior training determines how much time I spend on oxygen handling, but even the most knowledgeable person gets at least 30 minutes of review of basic handling principals...

The most important rule to remember is don't forget about adiabatic compression.. Oxygen being pressurised generates an incredible amount of heat as opposed to air. The heat generated along with any particulate matter can easily cause any fuel available to combust...

If you are going to do any cross filling make sure you use an oxygen compatible needle valve... and fill slooooooooooooooowly.

60psi per minute is a pretty acceptable rate.. If you are going to fill faster you must keep the gas cold....

 

[DrySuitDave]

Ok, allow this newbie to play the village idiot for a moment, and allow me to ask the question, where are all the injured and dead oxygen handlers?

I have an oygen clean whip to decant from a huge aviation grade low pressure cylinder and it takes about a minute to fill from 500 psi to 2000 psi. That is with the valve cracked open slightly. I let it set for 5 minutes or so to allow the cylinder to cool in case I can squeeze out a little bit more 02 before I disconnect it. I never touch the end pieces, and I always put the cpas on both ends right back on after use, and I never touch the insides of those.

At my LDS, they fill my 02 cylinder to about 2000 psi in about the same time, but when they boost it, they give me another 1000 psi in about 15 seconds. Why is their rig not blown to smithereens?

Lastly, I have heard all this technical sounding stuff about how oxygen in cylinders above 2500 psi is very dangerous, so where are the reports of all the injured Inspiration users who had problems with filling the AP 02 cylinder rated to 3000 psi to 3000psi?

I just got in a new DOT approved spare Inspiration 02 cylinder, made by the same company which is Faber I believe, and all of a sudden thanks to the infinite wisdom of the US Government, I lost 600 psi....

Now let me preface all this by stating I have not taken a gas blending class (my rebreather blends my gas for me) nor an 02 class as mentioned, so if myself and my LDS and all the rest of us who fill our 02 cylinders much quicker and to 3000 psi are all just living on borrowed time till we join the rest of the dead rebreather cylinders users, well hey, I can just blame it on ignorance! lol

Thoughts?

 

[Se7en]

It's the combustion triangle thingy. You need fuel plus heat plus O2 to get combustion.
Now O2 you got lots of, so you need to reduce the other two.

If you are absoulutely, 100% sure that you have nothing that can combust coming in contact with the O2, then you could bounce it around all over the show, no problems. Ditto, if you do everything slowly and carefully so there is no heat, you can have your gear as mucky and horrible as you like.

However, most of us tend to assume that there is at least some fuel, so we try to keep gas speeds and heat down, just to be safe. If you are scrupiously clean, you may get away with a bit more heat... but remember what you are betting on it...
One time in 10 000 it may save someone when they pick up a cylinder which has some oil or grease in the valve.

Sure, I'm probably being way conservative, but it doesn't cost much to wait a little longer.

Se7en

 

[padiscubapro]

DrySuitDave once bubbled...
Ok, allow this newbie to play the village idiot for a moment, and allow me to ask the question, where are all the injured and dead oxygen handlers?

I have an oygen clean whip to decant from a huge aviation grade low pressure cylinder and it takes about a minute to fill from 500 psi to 2000 psi. That is with the valve cracked open slightly. I let it set for 5 minutes or so to allow the cylinder to cool in case I can squeeze out a little bit more 02 before I disconnect it. I never touch the end pieces, and I always put the cpas on both ends right back on after use, and I never touch the insides of those.

At my LDS, they fill my 02 cylinder to about 2000 psi in about the same time, but when they boost it, they give me another 1000 psi in about 15 seconds. Why is their rig not blown to smithereens?

Lastly, I have heard all this technical sounding stuff about how oxygen in cylinders above 2500 psi is very dangerous, so where are the reports of all the injured Inspiration users who had problems with filling the AP 02 cylinder rated to 3000 psi to 3000psi?

I just got in a new DOT approved spare Inspiration 02 cylinder, made by the same company which is Faber I believe, and all of a sudden thanks to the infinite wisdom of the US Government, I lost 600 psi....

Now let me preface all this by stating I have not taken a gas blending class (my rebreather blends my gas for me) nor an 02 class as mentioned, so if myself and my LDS and all the rest of us who fill our 02 cylinders much quicker and to 3000 psi are all just living on borrowed time till we join the rest of the dead rebreather cylinders users, well hey, I can just blame it on ignorance! lol

Thoughts?

The reason for slow filling is to keep risks down.. If EVERYTH(ING is CLEAN (no fuel) and no particles for impingement you could probably instantenously fill a cylinder. By keeping the fill rate low it allows a larger safety margin when filling..

The most dangerous time is when you are first starting the fill... if you use a needle valve and slowly start the pressurization process (adiabatic compression is reduced) and then you can increase the rate.. doing a fast fill just causes the gas to get very hot, and you have to let it cool anyway and retop off.. do a hot fast fill to 3000 psi and when it cools doen I bet you have less than 2500...

The fastest I fill an o2 tanks is about 250-300 psi a minute, and thats in a cold water bath on cylinders I know are clean... re:my personal cylinders...
and I start them off slow.....

An example of a potentially dangerous situation is when you HEAR squeeling when someone is starting the fill, if there is fuel available things can happen....

I can fill a dirty cylinder 10,000 times without incident, and the 10,001 fill blows up.. well I'm probably dead... I'll play it safe.. and fill slowly..

Another point of contention, the higher the pressure the more unstable oxygen becomes... the percentage of free oxygen atoms increases causing a jump back and forth between an o2 and o3 molecule which releases energy.. That why the highest you usually see oxygen cylinders rated is 2400 psi...

a free oxygen atom is HIGHLY reactive, it doesn't want to stay free in wants to bind to something..