I wouldn't go skydiving with a bath towel.

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Burke

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Oceanside, California
So why am I scuba diving with a spare air?
Ok, first off let me say this forum is great, I found it about a week ago and just from reading back posts I have already learned more then I learned getting my ow certification.
Now for my question, when I got certified my instructor/lds owner convinced me and my dad and little brother that it was alot safer to have a Spare Air then an octopus, this made good sense at the time. So now I find myself diving with a 3.0 cu ft spare air(he sold my brother and dad 1.7 cu ft units) and I have felt perfectly safe.
Fast forward a year and I start doing alot of research into what other types of gear are out there and I decide that some day I am going to get myself a B/P and wing setup, as soon as I get out of school I guess. But I am not too worried about it because, while not perfect, my gear is fine. I may not be Doing It Right, but atleast I am not Doing It Horribly Wrong, and then I read how unsafe my spare air is, well that sucks because I can't afford a new reg(plan to get a 5 ft main hose and a necklace attached backup someday). I really work on not being a stroke but there is no way I am as safe as I should be(I am almost for sure doing stuff that a don't even know I shouldn't be doing) again, I am someday going to get more advanced training but can't afford it right now, so, do I dive my spare air carefully, not trusting it to be able to help me, or do I stop diving all together until I can get some better gear??
If anyone has managed to stay with me for this long I sincerely thank you and really appreciate any input you could give.
 
Depending on what type of 1st stage you have getting an octo may not be a major problem or expense. You can typically get an octo with hose from leisurepro or Diveinn for under $100. After you have this you can put your Spare Air up on Ebay and get at least that much for it. The only 1st stage I am aware of that requires an octo by the same manufacturer is Apeks due to the way they handle their intermediate pressure settings. Items like spare Air and pony bottles are no substitue for an octo and a dive buddy. Actually if I were you I would go back to the instructor and the dive shop he works for and make them exchange the Spare Air for a good octo and at least you backplate. I have not heard of any certification agency that allows spare air instead of a safe second.
 
Always dive with a buddy. Learn how to buddy breathe. Practice it with your buddy during a safety stop. Be comfortable with it. Have exceptionally good buddy awareness. And don't run out of air (or let your buddy--watch his/her guages as closely as your own). That spare air will only be needed if you screw up.

I don't know who told you that a Spare Air is safer than an Octo. They serve different purposes: a Spare Air is for when you run out of air (don't). The Octo is for your buddy when s/he runs out of air (don't let him/her). If there's no air in the tank it doesn't matter how many regulators are connected to it.

Others may disagree, but you pay close attention to the guages, to the location of your buddy, and practice the buddy breathing skill with your buddy and you'll be fine.
 
To clarify I always dive with the same dive buddy and he has an octo to share if needed. The deal with the spare air, as my instructor told us, is to use yourself if you run out of air, or to donate to your buddy if he runs out of air. So if I got another reg. I would just use standard buddy breathing in an ooa situation. We do always watch our air supply very carefully by the way. Also for anyone wondering I got my ow cert. through an SSI instructor.
On a side note is it common practice for the instructor and the student to get separated on the first open water cert. dive because they are both gathering scallops, the scallops where good, but that seems kind of wrong to me.
 
Originally posted by Burke
The deal with the spare air, as my instructor told us, is to use yourself if you run out of air, or to donate to your buddy if he runs out of air.

The major problem with the spare air is it just _isn't_ enough air. Think about the math. Say your at 60 ft, so that's 1-2 minutes to ascend safely, not counting the 3 minute safety stop. That's 5 minutes. Now with a beginners surface air consumption of 1 cu ft per minute, your talking 5 cubic feet of air AT 1 ATA. Even if you have an extremely good SAC of .5, that's 5 cubic feet of air at 33 ft.

There just isn't enough air in those bottles.

I would strongly recommend you pick up an octopus, you can get one for $50-$100 @ Dive Inn, or $100-$150 at a decent LDS. You mentioned you dive with a buddy that has an octo. That's great for you, but not so great for him if he's in the OOA emergency.

Personally I dive with an Octo for my buddy, and a 19 cu ft pony for myself. It's big enough to get me safely up from any reasonable depth, including a safety stop, and the philosophy that I hold with it is that if I ever use it, I've gotten myself killed diving, but I managed to get myself another chance.

[well, use other than making a kick-ass pool party entrance! :)]
 
I'm with the Funkster there. I use a pony myself. And I have an Air Source in case my buddy needs a hand. So I'm sitting on three working regulators with one redundant air source. If you're wanting a redundant air sourge, ditch that cartridge you've got and get a bottle with some time. Of course that all costs money.

I like the idea of trying to trade off the Spare Air to the dive shop who sold it to you in favor of an octo. Otherwise, you might consider letting us know which shop we're talking about so we can avoid them in the future . . . ? The octo shouldn't put you in the hole too much.

Otherwise the cheapest solution is to learn and drill buddy breathing. Not sharing an octo, but good, old fashioned buddy breathing.

Stay wet :dance:
 
An octo is cheap, compared to your life, or the life of your dive buddy. I know this sounds trite, but it's true.

As for the Spare Air. I have one, and it is only a last resort. It is only one step up from dumping your weights, and not that far of a step I might add.

My dive buddy and I have drilled with the spare air, and found that we could make a controlled ascent of 60 ft/min from a maximun depth of 60 ft. We found we had enough air for about a 3 min. stop at 15 ft, running dry just before breaking the surface. We were calm, in a controlled condition, and had lots of air in our tanks, so a sense of urgency never set in. In a real "out of air", the results would be somewhat different. Regardless of how well you drill. Reality has a way of doing that, you don't panic, but you are still not as "calm" as you would be otherwise.

(I'll use metric for the following, it's easier)

At 200 bar, the Spare Air has "approx" 81 Litres of air. At 1 bar (surface presure) a calm and relaxed person under minimal stress will consume about 12 litres per min. That gives you, at surface pressures, 6.75 min of air. But remember, you are not going to be calm, and you will be exerting youself to some extent. Further to that, you will be at 10? 20 metres? (33 to 66 ft) or deeper? start adding this up, and you will find that you will be out of air real fast. You will probably live to tell the tale, but you may not be as healthy as you were before you had to bail.

As I said earlier, a Spare Air is a last resort bail out, just one step above a weight dump. A situation I sincerely hope no one on this board will ever experience in real life.
 
Originally posted by Burke
...

On a side note is it common practice for the instructor and the student to get separated on the first open water cert. dive because they are both gathering scallops, the scallops where good, but that seems kind of wrong to me.

:confused:

First of all - the purpose of the 1st cert dive s to demonstrate your skills... There is a time availble for a swim but it isn't much. I am amazed that an instructor would lose buddy contact with a new diver. It "feels" like the instructor was more focused on dinner than on you. Granted, fecal matter happens; but it is the responsibility of the instructor to keep an eye on you! I'm sure that the certification agency would have less than happy things to say if they found out.

I'm almost afraid of the answer, but did you both surface after one minute of searching for your missing buddy?

(Oh yeah, and dump the spare air, if I remember correctly it was developed as an emergency egress system for helicopter pilots who ditch in water, not divers)
 
Gotta jump in with OD here - can you tell why your instructor promotes losing your buddy on your check-out dives in order to gather supper? something doesn't seem right.....

SS
 
Both my buddy and I use ponies, as does everyone I know in these parts. If for some reason you let yourself get in an OOA situation, then in all likelyhood your buddy is going to eb pretty low himself... so sharing an octo is just going to drain whatever remaining air twice as fast. We were tought buddy breathing, but we were taught to pass our pony reg ...

Not that this is how everyone else has to do it, but this seems to be the way divers are taught around here, and how I am comfortable. I would much rather have 19 ft3 strapped to my back just in case I need it then one of those 3 ft3 canisters.

BTW, I spent around $100 for the pony bottle and $150 for the pony reg. I just bought a used Poseiden reg of of ebay to use as my pony reg because I wanted to have it as a backup to my main reg, and my old pony reg (an oceanic) goes in my save a dive kit.

Ty
 
https://www.shearwater.com/products/perdix-ai/

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