Spare Air & Pony Tank

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eandiver:
I feel that I need to add this....at 80' spearing AJ's and not paying attention to my air I ran out( that right......dumbass.....) thanks to my buddy (Bret) we shared his tank to the surface and all was good. He had a spare air but due to the amount of air in his tank we opted to breathe from it and use the SA as a last resort..........2 days later he checked the SA and discovered it was filled with sea water...
Surely your not blaming Spare Air for you budddies lack of checking his life support equipment. I don't know of any equipment that doesn't fail sometime.
 
spiderman:
Surely your not blaming Spare Air for you budddies lack of checking his life support equipment. I don't know of any equipment that doesn't fail sometime.
This does bring to mind the proper service for this unit. It's not filled by the dive shop, so there is no industry requirement for a viz, and it's debatable as to whether or not there is a legal requirement for a hydro.

Does the manual indicate any recommended routine service? If not, then perhaps one shouldn't be so quick to be critical of the owner. How old was the flooded unit? How did it flood? The only thing I can think of would be that it was taken down when not filled. Does the manual caution against that? If not, then it should. It should be obvious that this could pose a problem, but if the owner didn't think about it, then all it would take is one dive to 100ft on the empty bottle to fill it to 3/4 or more full of water.
 
RichLockyer:
This does bring to mind the proper service for this unit. It's not filled by the dive shop, so there is no industry requirement for a viz, and it's debatable as to whether or not there is a legal requirement for a hydro.

Does the manual indicate any recommended routine service? If not, then perhaps one shouldn't be so quick to be critical of the owner. How old was the flooded unit? How did it flood? The only thing I can think of would be that it was taken down when not filled. Does the manual caution against that? If not, then it should. It should be obvious that this could pose a problem, but if the owner didn't think about it, then all it would take is one dive to 100ft on the empty bottle to fill it to 3/4 or more full of water.

The Spare Air unit is required to be sent back to manufacturer for annual maintenance. You will receive a sticker on the bottom of the tank to keep track of your maintenance record.

IMHO, whether it is the main air source or the redundant air supply, it is wise to treat them both equally important and have equal priority on regular maintenance.

It could be a defective new Spare Air unit, just like a defective tank valve or first stage..... we don't know. So it is unfair to the owner to jump to conclusion. The point here is to learn and treat ALL air source with equal priority.
 
RichLockyer:
This does bring to mind the proper service for this unit. It's not filled by the dive shop, so there is no industry requirement for a viz, and it's debatable as to whether or not there is a legal requirement for a hydro.

Does the manual indicate any recommended routine service? If not, then perhaps one shouldn't be so quick to be critical of the owner. How old was the flooded unit? How did it flood? The only thing I can think of would be that it was taken down when not filled. Does the manual caution against that? If not, then it should. It should be obvious that this could pose a problem, but if the owner didn't think about it, then all it would take is one dive to 100ft on the empty bottle to fill it to 3/4 or more full of water.
I don't own a Spare Air nor have I seen a manual or its service requirements. However, I do try to use common sense and would assume that since I need to service all other dive equipment on a yearly basis that the spare air should also get the same treatment. I can't imagine jumping in the water with any gear that I didn't check out. Those people that have used them tell about testing them underwater on a regular basis. Did he get in the water without a test. Would you use your pony bottle or any other tank without testing it first. One incident of a problem does not mean the product is at fault. If most users get the same result then I would blame the equipment. But until I see an objective evaluation I can only place the blame on the user. Again, I have never used a Spare Air and never tested one. I would like to know if there are true stats available on its effectiveness. I'm not really interested in stories for or against. Just if they have worked or not worked in real situations.

Also, if someone needs a manual to tell you not to dive it while it's empty they should find a safer activity. If it was empty before they got in the water then it's the fault of the diver and not the equipment.

I'm not trying to defend Spare Air. I just want to look at it objectively and not based on subjective opinion. I want to see the stats and the data behind the stats. I am fully aware that I can prove anything by manipulation of the stats, just look at the elections.
 
We're not sure how it happened. The unit was about 2 years old and was used regularly for around the boat stuff. We are both very meticulous about our gear and how we dive. It has a button that when full is raised and if it had been full of water prior to the dive we would have noticed the extra weight. We both believe it leaked out as we went down. It went back to spare air, was rebuilt and returned with no expanation. My point in relating the story is not to blame anyone (neither of us did) but to show what could happen. We learned several valuble lessons that day. I would rather go through life never making mistakes but since that is impossible I would prefer to have the living daylights scare out of me and walking away unhurt. It makes a lasting impression that way.
 
That's an interesting point about the SA unit being full of water, and another plus for a pony carried sling style. I always check the pressure of my pony before entering the water, and yes, breath off of the reg. Carried sling fashion, you can make sure that it is not leaking air during the dive.

I don't own an SA. I don't feel that they are adequate for North East diving. Here safety involve getting back to the anchor, or inflating a marker, not just getting back to the surface. Doing a safety hang in 1-2 kt current can put you out of sight of an anchored boat very quickly.

Warm water diving may be different. I might consider one for the tropics. Having said that, I would never trust one without some sort of gauge on it, and without testing it each dive. My 19cft pony drops 1000 psi in a month of diving just from testing prior to each dive.

I would probably opt for using a 6cf pony just because I can change regs, and monitor the gauge.
 
Well this has certainly been an interesting thread. Now assuming that anyone who dives in some sort of overhead environment will be carrying adequate redundancy already, then the spare air would only be of interest to the average rec diver puttering around in open water. If I had a failure at 3atm, I would want something that allows me to ascend immediately and safely. From 100' to 30' I can ascend at 60' per minute. Then slow to 15' for a 5 minute safety stop followed by a slow ascent to the surface. Normally I would double my air requirement to allow for rescuing a buddy, but if I was solo then I guess that's not a requirement. Based on my personal SAC, and assuming I did the math right, I would consume a little over 8cu ft for that ascent. The large Spare Air is almost 3 cu ft? I think I personally need a different solution.
 
Since this is the solo forum I can concede that the SA is of little use, If you're diving in the NDL in a non overhead enviroment, you can get away with the SA.

As said before, I test mine in a regular basis just to know the limits of the unit.

I don't dive outside the recreational NDL and never dive in an overhead enviroment without a buddy, in fact, the only OHE that I do are just a couple of preped wrecks and the penetrations are in the 10-20ft range, never done a cave but a few caverns have been explored. I don't feel OK if I can't see the exit, so I don't venture where the exit is out of sight. To venture into deeper OHE, I'll need aditional training and gear so for now I'm just fine.

My point is that for recreational diving in the NDL, the SA is a viable alternative to surface without the stress of emergency ascent, any gear can fail, so it must be tested regularly and apropiate maintenance procedures should be taken with any life support system.

If the diver has a SA just to hang it from the BC, so he/she can show off in the boat deck, the diver shouldn't be diving at all, it's the divers responsibility to know his gear and maintain it properly and regularly.

Every solo diver should take extra precautions when diving, so if you're diving solo, you should have the gear needed for the type of dive that's going to be made.

just my $0.02
 

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