Spare Air

[a22shady]

For me I would go with an Al 40 as my pony "spare-Back-up" that I sling. I don't like Spare Air because Even at 50-60' I can not make a safe sacent on it. Safe ascent is going at normal speed and doing whatever safety stops or "Decompression" if needed. I don't like the emergency ascent and would only do it with no choice. So if I am switching to Spare Air I don't have much of a choice as to my 40' I can make a normal ascent do my safety stop and out of the water. It eliminated the potential risk of a lot of problems.

For argument sake if was ascending already and had to do my safety stop at 15 ft for 3 min and I found myself out of air could the "Spare air" work im sure. That my big argument was not to carry it. If i am going to carry something and spend the money I want to be right and work for me. If i can't safely make it to the surface from where I am at then it's not useful for me and I would not buy it. So it's really only good for emergency shots to the surface. I am not interested as stated before in the Bends or doing things that increase the risk.

 

[DCBC]

Why is CESA taught? Quite simply because there are occassions where divers run out of gas and their Buddy isn't immediately available. We could certainly debate the attentiveness of a person who lets himself run out of air and isn't close to his buddy, but that's not the question being discussed.

Personally, I'm happy doing a 100' free ascent. If I'm in cold water with poor visibility and asked if I want to do a free ascent with a SA, or without one, I don't know many people that would choose the latter. Spare Air is an emergency air source only. If I need to use it, it has more air than I need.

I try like most divers to plan my dive. If I'm diving deep I ensure there are extra bottles. Getting to those bottles may be another hurdle. If I have a SA, I've got lots of air to go from whatever depth I may be diving to them, or in a dire emergency, the surface.

I use to use a pony but don't anymore. When do I require 40 cu. ft. of air to get to the surface? I certainly don't mind others using one, but I have the option of using doubles with redundant regulators and place additional cylinders outside of the wreck, whatever. If I'm travelling however, I take a spare air. If I'm on a reef, regardless of depth, the SA gives me all I need unless I'm doing penetration. Then it's the wrong tool for the job.

Like any tool, it has to be used properly. SA is a CESA aid. If you can't CESA with a SA from any depth, you should consider getting out of diving...

 

[SkimFisher]

Reminds me of a recent thread about what type of writing instruments people used to make notes underwater. Me? I use one of these...

They are made from a cellulo-organic material which is known for its depth compensating properties. Specially designed, these precision writing instruments are of hexagonal cross-section in order to accommodate divers wearing a range of gloves. The active ingredient in the instrument is a polymorph of elemental carbon, specially imported from the country of New Hampshire. Each instrument is coated with a patented substance known as "yellow paint" to allow the instrument to double as a signaling device - either at depth or at the surface. You'll notice that image I've posted above is a purpose-built piece of tech gear; easily identified by the lack of several failure points that are commonly seen in recreation pencils:

Plus, you'll also notice the model I use has no wireless transmitter, no switches to fail, etc.

Now, you may say "But Ray, isn't a pencil a life support system?" And of course you'd be right to ask that question. You'd sound like a bit of an alarmist nut, but you'd be right. Either way, I do worry about redundancy for anything that holds my life in its hands (if it had hands) so I always carry an appropriate backup...

Some folks may opt to carry a SparePencil^TM...

but I believe that something that was originally designed to carry just enough graphite to enable helicopter pilots to write "Oh sh-t!" before drowning has no place in tec diving! That's why in cases where you REALLY need redundancy many recreational divers opt to sling one of THESE as backup...

On the other hand, hard-core tec people like myself will often "dive doubles"...

which are perfect as this configuration allows you to completely isolate one pencil in the event of a "catastrophic" failure...

:shocked2:

 

[a22shady]

But you have the means where do not need to do CESA why would you want to put yourself or body at risk. I understand this is all "hypithetical" Yes I could make it from 60 or 100 doing a CESA with spare air. I could probably make it little more then 1/2 from a 100 on whatever breath I was to take and absolutly surface with SA. But it's the rush of only having very limited you know you can't play around and take your time getting to the surface it's an immediate grab the SA and go. I find it to much of a Risk. They say you can do a CESA chances are rare that anything will happen but I personally want to avoid them at all Cost.

 

[DCBC]

But you have the means where do not need to do CESA why would you want to put yourself or body at risk. I understand this is all "hypithetical" Yes I could make it from 60 or 100 doing a CESA with spare air. I could probably make it little more then 1/2 from a 100 on whatever breath I was to take and absolutly surface with SA. But it's the rush of only having very limited you know you can't play around and take your time getting to the surface it's an immediate grab the SA and go. I find it to much of a Risk. They say you can do a CESA chances are rare that anything will happen but I personally want to avoid them at all Cost.

No one wants to do a CESA, but in the situation outlined, you find yourself without a choice. This is why it's taught. The only choice is: would you like to take extra air with you (SA), or just do it on the breath you have?

Spare Air allows a diver more than enough air to get to the surface. You take a breath, ascend slowly, exhale slowly, take another breath, exhale slowly. In other words, do what you would do with a CESA except relax and slow down. There isn't any depth that you could be at outside of an overhead environment on air where you couldn't get to the surface safely.

Spare Air is an emergency breathing device only. If it doesn't suit your needs, don't use one. Personally I find it small enough to take with me while travelling and keep it convenient in case of fire in the home.

 

[a22shady]

No one wants to do a CESA, but in the situation outlined, you find yourself without a choice. This is why it's taught. The only choice is: would you like to take extra air with you (SA), or just do it on the breath you have?

My extra Air choice If there was one would not be SA it would be a 30 or 40. Or diving Doubles. But if I was diving for some reason I was not able to take a 30-40 and someone says they were all stolen all we have left is SA then in that Case I would take it. Something is better then nothing but I have yet to be in that situtation

For the people they work for thats great. For me I look forward to do more with diving where SA would not work such as Cavern/Cave diving and wreck penetration. I think you start diving with something like a 30-40 sooner the better and more comfortable you get. I just see too manu situations where a SA is just not sufficient enough. We can back and forth with millions of situations where One is better then other and get no where. Some believe it some do not. Like anything it's a specific tool.

Spare Air allows a diver more than enough air to get to the surface. You take a breath, ascend slowly, exhale slowly, take another breath, exhale slowly. In other words, do what you would do with a CESA except relax and slow down.

I have to belive this statement for you may be very true. But in the event someone who is carrying SA and runs out of air they will most likely panic and they know it will not last long and will most likely exceed the recomded Ascent speed and while gasping is Risking there chance for Lung over expansion as well as other things. I feel someone slinging a 30-40 would be more reserved as it's not a rush situation more of look Wow i only 300-200 left switch to back up signal buddy and head up.

 

[DCBC]

My extra Air choice If there was one would not be SA it would be a 30 or 40. Or diving Doubles. But if I was diving for some reason I was not able to take a 30-40 and someone says they were all stolen all we have left is SA then in that Case I would take it. Something is better then nothing but I have yet to be in that situtation

If you are ice diving or going into a wreck with minimum penetration, I agree that the minimum you need is a pony. I use to use them many years ago. You choose the best tool for the job. It sounds like you've identified what you require and that's great! Good diving!

 

[miketsp]

Reminds me of a recent thread about what type of writing instruments people used to make notes underwater. Me? I use one of these...



On the other hand, hard-core tec people like myself will often "dive doubles"...

which are perfect as this configuration allows you to completely isolate one pencil in the event of a "catastrophic" failure...

Since I've never used a twin-set like this, what's the handling like if you get an unbalanced mix like 3B one side and 2H on the other?
How do you calculate your run-time?

 

[H2O 70]

Tell us what you really think Skim...

Next question is why do you read new posts on "old subjects"?

I think the Spare Air has a use. If you are diving in shallower waters, >60ft, they are okay. A buddy of mine has a 3ft³ SA. We each took a turn and switched to it a 60fsw and made a slow, 30fpm, ascent. Both of us ran it dry within a breath or two of our heads popping out of the water. No safety stop.

I'm not going to go out and buy one, but I wouldn't mind having one the next time I'm in the Caribbean.

Other than this, there are much better forms of actual redundancy. For the cost of the SA, I'd get a lower performing reg and an actual bottle that make sense for your diving style.

 

[sabbath999]

For argument sake if was ascending already and had to do my safety stop at 15 ft for 3 min

I know I am pulling this out of context, since this is basic scuba I just want to make a point to NOOBS who may be reading this and think safety stops are mandatory.

One never HAS to do a safety stop. Required stops are deco stops, safety stops are optional (although a very good idea).