This is one hell of a discussion and one that really needs addressing. But unfortunatly I really dont know which ears it should be aimed at. because we are all talking the same language of ludicracy when it comes to this topic of "which tank is OK for O2 use!"
Here is the low down on how things got to this. Back in 95 when PADI introduced their Nitrox course there was a need to get things underway with Nitrox in NZ. A meeting was set up with PADI, NZU, OSH and dangerous goods. (now it is important to understand the difference between OSH and dangerous goods ( now ERMA) OSH dont give a dam if you go out, get a panel do some blending and blow your self to hell. What they do give a dam about is dive facilities who offer it. If they are dangerous in their ways and hurt someone in that process then that is when they will come down on you with the full force of 10 pulp fiction movies!!
Now dangerous goods' job ( yeah I had to really reach out here to really find out whay exactly their job is!) is is to make sure that any gear that comes into NZ is going to be safe for the punter.
Now we all have our own ideas as to how this occurs. I was a part of this initial meeting and I was just sitting there with my head in my hands.
There was a guy called Roger Marshall who worked for dangerous goods along side people like Mike Nankaville and Kim Combin. Now these were stand up guys who only wanted to sort things out safely for the punter. Roger now got it in his head that you needed special calculations to work out how elevated percentages of Oxygen would increase if the temperature was increased in the tank. Now this developed pressure calculation was introduced. Admittedly pressure does increase SLIGHTLY when O2 is introduced but Roger never gave out the exact results, he just deducted whether the tank was deemed safe or unsafe. bearing in mind that ALL air tanks should be filled at 15oC ( we all know that is bollocks!) So a list was made up and seeing that PADI only needed up to 40% Mix they did the calcs ONLY for 40%. Now I put my arm up in the corner and said "what about the techo???" bearing in mind that this was 1995-6 sometime. Noone wanted to rock the boat "Lest get the 40% first THEN work on teh higher mixes right " was the call.
Now (lucky for Roger) they were all made redundant - maybe he knew it was coming, and now there was a little list out in the market of a select few tanks that had these (bogus) calcs done on them. That is why you have to pay for any of these SP lab numbers because they have to get our friends in to do their (calcs) and thus YOU pay for them.
The extremly funny thing that happened just a few years ago ( hell its over 5 years now) we had another massive meeting, OSH, Dangerous goods, BOC, Air Liguide, NZU, PADI, hell all the guns were there, we had the meeting at dive HQ Greenlane when I was managing the place.
The topic was all this gas traffic mulakee. Long storey short I stood up and asked why only 40% when we were partial pressure filling and after i explained the process the room went silent.......... "You put PURE O2 in your tanks" they gasped????? Hell they didnt even know the process of blending? Then I spent the next hour explaining what procedures we have to ensure O2 service is kept at all times.
Heres some interesting knowledge for you. How often do you think O2 tanks get O2 cleaned from BOC or Air Liquide? 1 -2 -5 -7 years maybe? NOPE, every 10 years!!! Hows that!
anyway I digress......
So after the meeting I thought we were really getting places because everyone had agreed that the "world" standards we were following were good. - PROGRESS!!!!? Maybe not.......... some months weny by and nothing was heard about from dangerous goods then there was talk about making all facilities O2 clean their tanks for ALL applications wither it be membrane or partial pressure blending. again we fall into this chasm of clewless people.
So I gave up! Now you CAN get tanks Oked for O2 use, pay your money and GAZAAAANG it MAY get the all clear from the all seeing eye of Moredorrrr All breather O2 tanks are SP labed for O2 use when they are applied for - and cleared.
So there is a few things we can do?
1. do it all yourself and blend from home ( you will need a blenders cert AND fillers ticket issued by a periodic tester) BUT you will need to be officially registered by ERMA if you wish to fill from home ( yeah they are coming for you!!!!!) which means joining an outfit like NZU or Telarc for gas analysis quarterly.
2. Get NZU to try and sort it ( NZU are going through some massive changes here and due to their lack of manpower - basiclaly there is two of them in the office and thats it!) that is why you have been put on the burner because they are so busy.
3. Have a wip around to help fund change of gas traffic application for a few well used deco tanks
4. do nothing.
long post I know. Hope I didnt lose you after the first line
I put a nice little fishy picture at the end just to let everyone know why the hell we are doing this!!!!!!
this is a shot of the late, great "BORRIS" from the Coolidge. He has been dead now for a number of years but people used to flock from all round the globe to see this 600kg fish that was a big as a single bed!