Spare Air: some thoughts

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Do you recommend a Spare Air, or something bigger?

Whatever the diver wants to carry. Different people have different concerns and parameters. Some want to limit the equipment that they have to carry, others learn to dive so they can dive in tropical waters (and want to travel as light as possible), still others are influenced by the costs associated with purchasing (and servicing) another regulator and cylinder. Everyone has their own personal considerations.

I spoke to my son who's a Police Officer and asked him about his bullet-proof vest. I asked him why the Department didn't issue something that would stop a higher caliber round. The answer was that the Cops wouldn't wear it. It had to be something that would perform well, but wasn't inconvenient. I look at the Spare Air / Pony Bottle debate the same way. Some people only look at performance, others convenience. As long as they have any type of redundancy, it's better than them diving without.

For me it's more important that they realize the limitations of the equipment they purchase and their own personal limitations. As I've mentioned, I'm a stickler with my students about staying within touching distance of a buddy and have failed students who don't comply to my satisfaction. They have to plan, dive together and be competent in sharing-air/buddy breathing (horizontally and vertically). That said, conditions are not always within one's control. People don't always do what they are suppose to do and when an emergency occurs (and it will if they dive long enough), their emergency plan, equipment and lack of panic and willful actions will make a difference.

I could write a book on how many emergencies I've been through. It hasn't been a lack of planning; the military and commercial fields don't allow this. people make mistakes, equipment malfunctions and s*it happens. We prepare for that day.
 
FWIW, when I took my AOW the LDS took us on a charter that required pony bottles for divers that were not AOW on all dives below 60'. So far they seem to be the exception and not the rule.

A great rule for the LDS. It promotes equipment sales and training.
 
2- I held my breath by maintaining firm control with my diaphram. This would prevent the flow of air in or out by an external force that was not as powerful as that of my own muscles.

3- If I did number 2, while ascending from any significant depth, I'd most likely end up with an embolism.

Provided the airway is open, when you ascend the expanding air will simply flow out.

The diaphragm expands your lungs, it doesn't seal them off.

(Note I'm not a doctor, and my understandings may not be anatomically accurate).

And no, I don't mean "number 2" as in the usual sense of bowel elimination.

LOL!

That would be a great episode of House. Patient develops an AGE via an extremely uncooperative... well you know.
 
Provided the airway is open, if you ascend, the expanding air will simply flow out.

The diaphragm expands your lungs, it doesn't seal them off..

The expanding air that "will simply flow out" is the breath that you had just taken prior. I don't think this fact is in dispute.

If you are "holding that breath" then it's not going to flow out.

That's the defnition of "holding".

Some definitions:

To close within bounds, limit or hold back from movement

Remain in a certain state, position, or condition

Keep from exhaling or expelling (yup thats the exact definition from WordWeb, a downloadable taskbar thesaurus.


#36 at the bottom

http://www.wordwebonline.com/search.pl?w=hold


The problem is in the semantics, and the large number of people reading these boards, some of whom might take the term holding your breath as meaning to hold the last breath taken at depth and not allowing it to flow out of your lungs.

And you really can't blame them for that.
 
The problem is in the semantics, and the large number of people reading these boards, some of whom might take the term holding your breath as meaning to hold the last breath taken at depth and not allowing it to flow out of your lungs.

And you really can't blame them for that.

If you learn to dive by reading something on the Internet, that is bad.

If you take it out of context, e.g. by googling for a term and failing to read the entire thread, that is worse.
 
And you really can't blame them for that.

No, but I can blame the people who were too lazy to teach them how to dive. :D

There are multiple semantically inaccurate things pervasive in scuba education. "No decompression limit" is an example.

Some dive educators are passionate about teaching what's really happening and how to go about maneuvering through the water column. Others simply want to add 20# to a student, affix them to the bottom, go over a few things and move on to the next. Still others may find breath control to be dangerous, and that's their prerogative.
 
If you learn to dive by reading something on the Internet, that is bad.

I take that to mean "any learning on the internet" is a bad thing.

Do you see the irony? I wrote something very specific, and you generalized it. Given the existence of behaviour such as this, where persons can take something written in a specific way and extend it in ways the author did not intend, you have a medium that is ripe for misunderstandings.

Such a medium is not an appropriate mechanism for being the sole source of information for learning how to conduct an activity in a hostile environment. I leave it to others to debate the difference between "learning to dive" and "learning some things about diving."
 
Do you see the irony? I wrote something very specific, and you generalized it. Given the existence of behaviour such as this, where persons can take something written in a specific way and extend it in ways the author did not intend, you have a medium that is ripe for misunderstandings.

Such a medium is not an appropriate mechanism for being the sole source of information for learning how to conduct an activity in a hostile environment. I leave it to others to debate the difference between "learning to dive" and "learning some things about diving."
That's what happens when people play at being stupid (usually called bring a troll). Even when they are actually stupid they rarely make that sort of error.:D
 

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