Spare Air: some thoughts

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I just don't see the logic behind the argument against SpareAir. As DCBC's stated, SA is basically designed to provide a few breaths when doing a CESA. You don't need 19cu ft of air, you need a few breaths when doing a CESA. How much does one breath expand your CESA envelope? The typical rec diver is not going to face an equipment problem/ OOA in an over head environment or in a deco situation. They more likely will face an OOA situation where no buddy is immediately available and choose to do a CESA. I think its indisputable that in a CESA situation, SA is better than nothing. Don't think of SA as a pony, or backup gas, thinking purely on the terms of it being a CESA assist. In that light, all the arguments against SA are basically arguments against CESA. "you have such bad dive planning if you have to use a SA/CESA" "your buddy skills are horrendous if you have to use a SA/CESA".
 
I just don't see the logic behind the argument against SpareAir. As DCBC's stated, SA is basically designed to provide a few breaths when doing a CESA. You don't need 19cu ft of air, you need a few breaths when doing a CESA. How much does one breath expand your CESA envelope? The typical rec diver is not going to face an equipment problem/ OOA in an over head environment or in a deco situation. They more likely will face an OOA situation where no buddy is immediately available and choose to do a CESA. I think its indisputable that in a CESA situation, SA is better than nothing. Don't think of SA as a pony, or backup gas, thinking purely on the terms of it being a CESA assist. In that light, all the arguments against SA are basically arguments against CESA. "you have such bad dive planning if you have to use a SA/CESA" "your buddy skills are horrendous if you have to use a SA/CESA".

The logic is that for just a little more cost and burden, you don't have to perform a CESA if you find yourself OOA. With a small pony bottle you can perform a normal ascent (ascent rate and rest stop) eliminating any potential added risk associated with a CESA.

But I do understand how the increased burden of a pony bottle may be the deciding factor in opting for a spare air.
 
I noticed that the "solution" to several of the situations mentioned above require the presence of a buddy. What buddy? And what alternate second stage? Oh, I forgot. You guys don't know how to dive the old way.:D

It's certainly possible to dive reasonably safely without a buddy, however current recreational training is based on having a competent buddy, so I included all the places a buddy is better than 3 CuFt of air.

FWIW, aside from the deco & entanglement issues, which a SA can't fix anyway, most of rest of the list can be completely eliminated by diving within safe CESA limits, and doesn't even require a buddy, and quite a few are easily fixable underwater, although I wouldn't recommend this to new divers.

Terry
 
Again you make a good point, however to judge it inadequate a diver will have to know their actual free-ascent / CESA envelope beginning with a full and empty breath. I cannot be sure, but I believe most of the naysayers have absolutely no idea what they really require. More is better than less in most instances, but it's easy to throw stones at the unknown.

Absolutely.

To be clear, I'm not making that argument or taking a stand on SA, just summarizing a multitude of posts/threads.
 
You don't need 19cu ft of air, you need a few breaths when doing a CESA.

Why do you need a few breaths? Were you allowed to take a few breaths during your CESA training?

I think its indisputable that in a CESA situation, SA is better than nothing.

Disputable or not, that's a terrible point. Personally, I look for good solutions, not "better than nothing" solutions.
 
Spare Air-It takes the E out of CESA
 
I just don't see the logic behind the argument against SpareAir. As DCBC's stated, SA is basically designed to provide a few breaths when doing a CESA. You don't need 19cu ft of air, you need a few breaths when doing a CESA. How much does one breath expand your CESA envelope? The typical rec diver is not going to face an equipment problem/ OOA in an over head environment or in a deco situation. They more likely will face an OOA situation where no buddy is immediately available and choose to do a CESA. I think its indisputable that in a CESA situation, SA is better than nothing. Don't think of SA as a pony, or backup gas, thinking purely on the terms of it being a CESA assist. In that light, all the arguments against SA are basically arguments against CESA.

Beautifully said. I wish this had appeared as the second post/first response to fdog. We could have saved a lot of time had this and certain other gems appeared earlier in the thread.

Now since you are calling on us to rethink the way we are thinking about SpareAir, may I humbly make a suggestion of my own? It is this: Instead of thinking of the discussion as an argument for or against a practice like carrying a SpareAir, we should think of the discussion as trying to subdivide the set of all divers into those who would and would not benefit from the practice. You can see that kind of thinking in part of your own post when you talk about the typical Rec diver and in several of the posts I have read in this thread. It really helps depersonalize the discussion.

In that light, your posts seems to suggest that the divers who will benefit from SpareAir are those who have made choices such that they are not going to carry another redundant source of air, and have made choices such that a solo CESA is enough of a possibility to outweigh any considerations concerning the small weight and bulk of a SpareAir.
 
FWIW, aside from the deco & entanglement issues, which a SA can't fix anyway, most of rest of the list can be completely eliminated by diving within safe CESA limits, and doesn't even require a buddy, and quite a few are easily fixable underwater, although I wouldn't recommend this to new divers.

Hey Terry, I don't think anyone is saying not to dive without a Buddy. The point is that if you have to do a free-ascent / CESA it's safer to have a redundant air supply. Do you disagree?
 
Perhaps you should take a poll who takes a Pony Bottle with them when they fly off on a tropical vacation. Certainly not me! When I'm working that's a different story, the company pays for the tons of equipment that I'll require.
I guess my life has been a bit short on tropical vacations, during my temperate winters I'd ski, and once I moved to the tropics that somehow became irrelevant.
Thal pardon me for saying so, but you seem to have some difficulty relating to non-scientific divers. I could talk from a military or commercial diving perspective but again, this is the Basic SCUBA Discussion thread!
Each of us is a product of our environment and experiences. Yes, I think that, by and large, entry level training of recreational divers is sub-optimum and I refuse to accept that and play along. My experience has been that it's not a big deal to teach an entry level diver to perform a 60 foot free ascent. My experience is that it is not a big deal to teach an entry level diver to hold his or her breath for two minutes. It only adds about an hour (including practice time) to the entire course, it does not providing them with an entire 100 hour course. My question to you, therefore, is might it not be better to apply to the recreational programs that you run what you have learned as a result of your somewhat broader experience, rather than pander to the party line and slap a Spare Air bandaid on the problem?
When I train a new diver, a good portion can accomplish an emergency ascent from 50'. One breath is required. For the others that have difficulty, certainly no more than one or two additional breaths are needed. If they didn't have an initial breath to begin the ascent another would be required. Now we are up to a maximum of 4 breaths of air that are required. If this is all that's required, a Spare Air provides more than enough gas. If not, perhaps they need more training.
I've never had a student who could not, easily, accomplish a 30 foot free ascent during the course and a sixty foot free ascent when they went for their 60 foot card (24 dives later). I'd submit that their comfort with breath hold diving is the critical item here.
 

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