How long is air in the tank good during storage?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

skye

Contributor
Messages
73
Reaction score
0
Location
FL
Do to deployments I don't get to dive on a regular basis and I would like to find out if there is a limit on how long air can be left in a tank before it is unuseable?
 
Thank you. I have asked around but it seems like there are different answers. Will the oxygen content deplete at all?
 
skye once bubbled...
Will the oxygen content deplete at all?

As long as the air is dry - not so you'd be able to measure it.
there is the issue of do you really want the bottle under load for a year or more?
all manufacturers recomend storeing tanks with less than 50 psi in them. nothing makes me cringe more than an ad on ebay claiming " tank stored full for the last 2-3 decades"
 
I am more worried about the fatigue from the changing pressure of a tank in use than that of one in storage at any normal pressure.

When I worked in the Navy nuclear program we were far more concerned about the number of heatup/cooldown cycles on the pressure vessel than the number of hours (years) the system was under pressure.

Hey, if the air passes the smell, taste check, use it.

Then if it is time, get a new VIP and/or hydro and get it refilled and use it again.
 
Air is cheap, I'd empty it, and get a VIP/fill. Shouldn't run more than 10 $, and I'll pay 10 for peace of mind.
 
I would only keep a tank full for about 6 months before refilling it. At the end of the day though, if the air don't smell stale, then it is probably fine.
 
If its a steel tank some oxygen MAY have been used up. If ANY moister has gotten in it it bagins to OXYDIZE, or corrode, anyways this usesd oxygen (things wont rust w/o it).

I know I wouldnt use it, if it was in a steel tank, and in an AL I would do the taste/smell test. You could always ave the air O2 anylyzed at your LDS>
 
Thank you all very much for the information. The breaks between tank usuage are sometimes for a couple of months and the tanks are stored at a constant tempature of 78 degrees, but I wasn't sure if the o2 content would be the same, I use an AL60 and AL80 tank.
 
I just bought an AL80 tank that had stored full and had not been used in 4 years. After 4 years the air was still quite good and still read 2900 PSI on it although I took it for a VIS and Hydro for safety reasons.
 
https://www.shearwater.com/products/peregrine/

Back
Top Bottom