Should I get a Spare Air?

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it is 1.6. Still "safe" by some peoples
standards but something I avoid.

I like the sound of your rig. I'm a little
more than "safe." I'm 62. I'm no longer
an athlete. I go down, I come up, I sightsee
while under. I need a few extra precautions
that someone younger and in better condition
might not need. I don't care to become an
emergency for myself or my dive buddies.

As Dirty Harry said: " A man has to know his
limitations."
:doctor:
 
I almost bought a 30cfu pony to backmount on my 120hp for deep dives and penetration.

Instead I went with a 40al and rigged it as a stage. I have about 50 dives with and I love it (plus it's nice to have as much air as a set of 80al doubles). Backmounting is dangerous in that it creates a entanglment hazard and that you can't get to/see the valves plus anything smaller than a 40 is just going to give false confidence, 20cfu is just not enough air to help if you really need it.

Plus now as I get into more advanced diving I don't have ditch a pony, I can keep using my 40 as a stage. In the future I might be using: double 120hps (I havea dry suit so overweighting won't be an issue), 1 40lbs with bottom mix, and, another with 100% O2 - lots of gas there.
 
and as others said, I wouldn't trust it.

As for a pony bottle, I owned and dove with a pony for some time. It always added stress, and never relieved it. I found that you would do better to...

1) Check your guages often! Plan your dive, know your SAC and DAC for your planned depths. But check your guages.

2) Use a bigger tank if needed. I dive HP120s so I always have extra air for those little problems during the dive. Carry the right amount of gas to begin with, and keep the clutter to a minimum.

3) Need redundancy? Need redundancy? I dive a lot with an H valve on my HP120s, but I feel safer with an isolation manifold on my doubles.

3) Train and rely on your buddy! Buddy skills are often the most neglected and yet the most important skills that we need. S/He is your best redundant air supply! Work on signalling and air shares while at your optional stop. Work on intimacy during the dive... you should both be up each other's butts, so to speak.

Most pony bottles are not reserved for only bail outs that they were first intended for... many times their air is used in planning a dive, and not as a contingency. This makes them useless in my book. If the dive is deep and complicated enough to require a deco bottle (or more) by all means get the extra training to be able to use them wisely and safely. But just slapping on a pony (or spare air) does little to increase your saftey factors, and can go a long way to diminish them.
 
Lawman once bubbled...
If I have an OOA situation I will be going up and even if below the MOD for that nitrox it would only be for a matter of seconds.

You should not just be swimming around and run out of gas, that’s bad gas management! So the justification for a bail out bottle is that something unexpected happen such as an equipment failure that compromises your primary SCUBA or associated gas supply or a situation that temporarily prevent you from surfacing, such as entanglement, beyond the capacity of your primary air supply.

In this case you will have to identify the problem, make the decision to switch to the bailout (versus your buddy’s octo), make sure that your buddy knows what’s going on, and then start to surface. Additionally if you are not by the anchor line you may wish to float a surface marker to give you a visual reference for ascent.

All of this will take more than a few seconds.

Lawman once bubbled...
It might help to throw off some nitrogen on the way up as well.

I don’t understand the point here. If you size the bailout bottle properly you have time to ascend at the proper rate (30 fsw/sec) and make a safety stop. What is the situation you envision that makes it helpful “to throw off some nitrogen on the way up?” If you’re talking about a deco stop that is a whole other discussion and has nothing to do with a bailout bottle.

Mike
 
NetDoc once bubbled... [/B]
It always added stress, and never relieved it.

Pete,
Would you explain how it caused you added stress?

My position is that for recreational diving (no overhead, no deco), carrying a pony as a bailout bottle is a valid approach that makes diving inherently safer.

1) Check your guages often! Plan your dive, know your SAC and DAC for your planned depths. But check your guages.

I totally agree, that’s good gas management and has nothing to do with a bailout bottle.

2) Use a bigger tank if needed. I dive HP120s so I always have extra air for those little problems during the dive. Carry the right amount of gas to begin with, and keep the clutter to a minimum.

I have two PS HP120s and love them, but more gas in the tank doesn’t help if you have a fist stage failure or burst hose, it just makes more bubbles.

3) Need redundancy? Need redundancy? I dive a lot with an H valve on my HP120s, but I feel safer with an isolation manifold on my doubles.

Neither an H valve nor doubles with an isolation manifold provide 100 % redundancy. For both there are failure modes that without intervention result in the loss of all gas. In the event of a free flow or burst hose both of those solutions require the manipulation of the correct valve. Additionally there are circumstances where these options are not financially practical and they don’t lend themselves to air travel.
Although I have yet to have an OOA situation I imagine there is no better sight than looking down and seeing the pony reg, valve, and SPG reading 200 BAR right in front of you.

3) Train and rely on your buddy! Buddy skills are often the most neglected and yet the most important skills that we need. S/He is your best redundant air supply! Work on signalling and air shares while at your optional stop. Work on intimacy during the dive... you should both be up each other's butts, so to speak.

Again I total agree, but there are situations where you dive with new buddies or it may be that your buddies problem is what caused you to need the bailout.

Most pony bottles are not reserved for only bail outs that they were first intended for... many times their air is used in planning a dive, and not as a contingency. This makes them useless in my book. If the dive is deep and complicated enough to require a deco bottle (or more) by all means get the extra training to be able to use them wisely and safely. But just slapping on a pony (or spare air) does little to increase your saftey factors, and can go a long way to diminish them.

I think the discussion was about using a pony bottle as a bailout. Would you explain how doing so can diminish safety?

Mike
 
Personally speaking I rarely know what I will end up doing underwater. Having said that I plan for the unexpected. I feel a 30 would bring you safely to the surface from 100' with a safety stop to boot. Having a little left to swim to the boat if necessary! I on the other hand use a thirty for 50/50 deco pourposes. It will give me about two good dives from 1- 30 cu ft tank.
My preference is 40 or larger, you can never have to much air. Basically speaking, the only thing to kill you would be running out of it!
I have always wondered why more divers don't carry spare air of one kind or another, much less the shops pushing it as a saftey mechanism. I realize everyone has a different adjenda when they dive and can't be lumped into one catagorie, much less should they. For those of us who, not to draw fire, but, solo diving requires a higher level of redundancy and awareness. Carrying it under your arm is painless. It may require some practice becomming proficient with it, as any new piece of life saving equipment would, as well as setting it up propperly. This modest addition will prove invaluable if pressed into service. The only problem I ever faced while useing a pony was getting my fin off on the left side. Whether using a 30-40-or an 80, having the air is better than wanting it. To some it may be a waste of time and money. Others may see it as a last line of defense against drowning. I feel it's common sense and shows a higher level of responsibility. Irreguardless it's your decision, make it a good one!
Wreck/Tec
 
Pete,
Would you explain how it caused you added stress?
Certainly… More is not necessarily better. Clutter=confusion=stress. Have an extra second stage… which is which? Having more to carry… on the back I have to worry about entanglement and swapping between dives. As a sling (which I have done with bigger tanks) it gets in the way with my mobility, especially while trying to get out of the suds.

My position is that for recreational diving (no overhead, no deco), carrying a pony as a bailout bottle is a valid approach that makes diving inherently safer.
A pony/bailout is contraindicated on such a dive. It adds an extra task, and lends itself to abuse by those not trained in its use. It gives a diver a false sense of security that they have more air that they can use, which might put them into mandatory deco time... a glass ceiling if you will. You should never be in a situation where you can’t swim freely to the surface.

I totally agree, that’s good gas management and has nothing to do with a bailout bottle.
Actually, most people who dive a pony, get tired really quick of carrying around all this weight for no apparent benefit. SOOOO, they start using it as part of their gas supply, and NOT as a bailout. It will actually detract from good gas management. As I used the word “most”, I must qualify that I have not dove with the vast majority of divers, but all of the pony carrying divers that I have dove with have used it in their gas/time calculations. Again, it might very well mean that they enter into a mandatory deco zone… which is far more dangerous for an OOA diver. Gas management is only PART of a great dive plan… contingencies and buddies are just as important. Your buddy IS your bailout bottle.

I have two PS HP120s and love them, but more gas in the tank doesn’t help if you have a fist stage failure or burst hose, it just makes more bubbles.
Where is your buddy? Where is the surface? If you are within NDLs, you can surface with a burst hose or a first stage failure.

Neither an H valve nor doubles with an isolation manifold provide 100 % redundancy. For both there are failure modes that without intervention result in the loss of all gas. In the event of a free flow or burst hose both of those solutions require the manipulation of the correct valve.
Where is your buddy? Where is the surface? Where is your training? If you can not correctly turn the right valve, then you should not be using that equipment. Your training should have covered free flow, either from a reg or a burst hose.

Additionally there are circumstances where these options are not financially practical and they don’t lend themselves to air travel.
Although I have yet to have an OOA situation I imagine there is no better sight than looking down and seeing the pony reg, valve, and SPG reading 200 BAR right in front of you.
Diving is optional… don’t make any dive until you have the proper equipment and training. It’s just not worth the risk. Traveling? Make arrangements ahead of time… I do. What is best is NEVER seeing an OOA situation, second best is seeing my buddy right beside me.

Again I total agree, but there are situations where you dive with new buddies or it may be that your buddies problem is what caused you to need the bailout.
I dive with new buddies all of the time. I aggressively train them and let them know what I expect from them and what they can expect from me. I can not imagine a buddy’s problem resulting in my OOA… unless I was also OOT (Out of Thinking, or Out of Training).

I think the discussion was about using a pony bottle as a bailout. Would you explain how doing so can diminish safety?
I thought I did in the first post, but will try once more here.

I would postulate that %99 of all OOAs in the OW environment are from human errors and not from equipment malfunctions. Why then would we throw a hardware solution at a software problem? Why would we consider something safe when we see it continually abused?

Divers are constantly trying to push the envelope. That is not essentially a bad thing, but we need to do it logically. Training is the key here, and continued training after that. Take a course that teaches gas management before you try and manage gasses. Practice your buddy skills and your air share drills. Work on becoming a more aware diver… and when you are ready to move into technical diving, do so with care and the proper equipment.
 
How did Lawman asking about deciding to carry extra gas degrade into an entry level persons inability, ( in your opinion ), to manage a pony? I'll use myself as an example. When I was first turned out shortly there after I got a pony. It screwed up my trim, and it was confuseing, however it did give me peace of mind knowing I had extra gas in the event of an emergency. I had my hands full with the basics, adding the pony was overload in the sense that it changed so many aspects of the dive, it took me awhile to figure out what was going on. As for those predisposed to use a pony as extra gas and go into deco, you don't need a pony to do that. Larger tanks are sold every day. Although I would be remis if I didn't say I hadn't abused the pony as extra gas later on. It would be nice if we lived in a perfect world and people wouldn't abuse things. In this case diving beyond ones means perhaps, or being the poster boy for pony abuse. Hopefully, if the new diver was trained propperly, and they posess any common sense, are fortuneate enough to have a respect of the unknown, as well as seek a knowledgeable partner, they will be on the road to self preservation. That was my story, others may be swifter, and or smarter and able to manage better.
As for the more experienced and adventureous diver, this hardly qualifies as a hazzard. If any thing it's yet another topic we can respectfully disagree about and hope no body gets hurt with.
Wreck/Tec
 
Not sure if this thread has been "degraded" or been improved by the discussion of safety. Your post has been the best anti-pony statement to date. Thanks for sharing!!!
 

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