How long a tank can remain fully filled?

[Gilldiver]

Now for everyone, next time you go to Grandma's check her O2 bottle, is there a shelf life or use by date? Does it say store for 3 or 5 months only?

 

[Gilldiver]

Last, the type of bottle I see being the worst are the small ones used for suit fills. On a long deep dive with a lot of up and down a dry suit diver can go through a small bottle of gas quickly and be hitting the add button with nothing left in the bottle.

Then you can get some water into the bottle and because it is so small, it can become a problem much quicker.

 

[Doc Harry]

If you keep your tanks in vis, don't drain them below say 300 PSI in the water (if you do, just take the valve off and check for water intrusion) and use a compressor that in at least fair maintenance, you can keep a tank filled forever.

That advice will keep you out of trouble 99.999999% of the time.

Note too that they kept the tanks heated to a little over 100 degrees F for the full time. It was a torture test, as it was intended to be, not a simulation of what happens to a tank in real life.

My garage where I store my cylinders gets over 100 degrees all summer. A shed in Florida can also get over 100 degrees. The temp is rather high but not uncommon.

It's also worth noting that while the report on the 3% O2 tank that killed the guy said it had been sitting in a hot shed for 3 months since he last used it, it didn't say that was when it was last filled - it may have been festering for years.

The guy who died had used this same cylinder 3 months prior to his death.

 

[Davidstealey3]

Drain tank, take valve off, look in tank:

If dry, put new O-ring on valve, put valve back on, transfill 50-100 psi from another tank, get filled.

If wet, Rinse out with clean HOT water, get the tank as hot as your tap water can (120-130F), drain tank, while inverted, blow clean air into tank for 30 - 40 seconds, check for wetness, if wet, (it will not be) invert and blow some more air into it, When dry, put new O-ring on valve, put valve back on, transfill 50-100 psi from another tank, get filled.

This is not Rocket Science.

slap a sticker on it with no shop name and punch a new date and who needs to pay for VIP's and cleanings anymore

 

[Davidstealey3]

Drain tank, take valve off, look in tank:

If dry, put new O-ring on valve, put valve back on, transfill 50-100 psi from another tank, get filled.

If wet, Rinse out with clean HOT water, get the tank as hot as your tap water can (120-130F), drain tank, while inverted, blow clean air into tank for 30 - 40 seconds, check for wetness, if wet, (it will not be) invert and blow some more air into it, When dry, put new O-ring on valve, put valve back on, transfill 50-100 psi from another tank, get filled.

This is not Rocket Science.

not to be an ass, but are you a VIP inspector? if it was that easy everyone would do there own tanks and there would be no need to be certified

granted it is not hard to do, but say you screw up some how doing this and you get some rust, aluminum oxide, or pitting in your tank, and come time for the next vip you try to blame the inspector for not doing his job right. it is best to let the pros do the job they were trained to do. and if you actually go to a dive shop on a regular and dont get all your gear off the internet, they might take a look in the tank for you at no charge.

 

[Gilldiver]

not to be an ass, but are you a VIP inspector? if it was that easy everyone would do there own tanks and there would be no need to be certified

granted it is not hard to do, but say you screw up some how doing this and you get some rust, aluminum oxide, or pitting in your tank, and come time for the next vip you try to blame the inspector for not doing his job right. it is best to let the pros do the job they were trained to do. and if you actually go to a dive shop on a regular and dont get all your gear off the internet, they might take a look in the tank for you at no charge.

So, you need to be a certified VIP inspector to look inside of a tank to see if there is any wetness? Do you also need to be a certified regulator tech to work on your own regs? Say to replace a hose or O-ring?

Yes, it is that easy. Perhaps you have fallen into some zone where you think this is all magic done in the back room with the secrets of the SCUBA Gods.

VIP inspections once per year is a good thing, I just do it more often if I think there was an opportunity for something to have gone wrong. My tanks range in age from 1960 to the newest at about 7 years old now. In the last 30 years of active diving I have never had to have a steel or aluminum tank tumbled. I've whipped more then a few, but never tumbled.

Try to remember that steel tanks and their problems are nothing new, they have been used since the birth of SCUBA and I never heard of shops having tumblers till "tech" got started and people got paranoid at any rust.

And yes, I store them full and they all pass HYDRO, even the 49 year old one. I do change the blow out plug when I rebuild the valve at each HYDRO. That means once every 5 years.

 

[Luis H]

not to be an ass, but are you a VIP inspector? if it was that easy everyone would do there own tanks and there would be no need to be certified

granted it is not hard to do, but say you screw up some how doing this and you get some rust, aluminum oxide, or pitting in your tank, and come time for the next vip you try to blame the inspector for not doing his job right. it is best to let the pros do the job they were trained to do. and if you actually go to a dive shop on a regular and dont get all your gear off the internet, they might take a look in the tank for you at no charge.

Be aware that a large number, if not the vast majority, of “pro” VIP inspectors are not certified by anyone. There are many very qualified inspectors that have never been certified. IMHO, VIP certification is a great idea, but be aware that it is relatively new.

As Pete mentioned this is not rocket science.

Oh, BTW, Pete may not be a certified VIP inspector, but if you do a bit of searching you will find that he is far more qualified than most VIP inspectors can even hope to be.

I am a PSI certified VIP inspector… I got certified three years ago for the first time. On the other hand I have been inspecting tanks for almost four decades. The certification was for the most part a technicality since I have been inspecting tanks long before PSI / PCI ever excisted. In addition I am now also an engineer and occasionally I have done some consulting for PSI / PCI.

Certification and training is a great idea to add uniformity and credibility, but it is not the only way to obtain knowledge.


BTW, Pete
I started tumbling tanks in 1971 when I started working on my first dive shop (long before tech diving). I hate tumbling tanks.

 

[Davidstealey3]

i am just saying it is not something everyone should go out and do, especialy new divers.

i do have VIP certs from PSI and SDI, and there is a lot people can learn from taking the course. you guys that have been diving since the dawn of it are smart people and this stuff had to be started somewhere, and we thank you for that, but the new diver and some semi experienced people just should not be doing this on a regular.

i know this is just an industury standard and not a lae written in stone just putting it out there to be seen and heard. you guys are right its is not rocket science just think people should be shown what to look at and how to do it before going out on their own to start.

didnt mean to start a big fight over this, i mean the orignal question was just how long the air could be stored in the tank in the first place

 

[Rhone Man]

Quick anorak point: if you have filled the tank with a helium blend, the helium will slowly leak out over time.

Be aware that a large number, if not the vast majority, of “pro” VIP inspectors are not certified by anyone.

I worked as a VIP inspector between high school and college. I don't think that you even could get certified as a VIP inspector in those days, even if my employers had wanted to (they displayed no such inclination). Truthfully, it isn't rocket science. I don't think tank owners should be restrained from inspecting their own tanks any more than car owners should be restrained from changing their own oil.

 

[captain]

As is the case a lot of times, PSI was a company started without an existing need for it services and then went out and convinced the industry that did quite well without PSI that it needed PSI.
Many businesses are formed by convincing a business owner they need the services that business provides.
Sometimes it allows a business to cut costs by either eliminating personnel or in house training by contracting it to an outside source.