*Another* Really Stupid Question

[Reg Braithwaite]

So from my first stupid question, I gather that diving thirds or even more conservatively is all about unexpected things that delay a return to the exit in an overhead environment like silting out, getting lost, that kind of thing.

Several people commented that the likelihood if a team member suffering catastrophic gas loss with manifolded doubles is remote.

So... If the possibility of a catastrophic gas loss is remote...

Why carry a long hose with doubles?

 

[TSandM]

Reg, first off, your question is in the technical diving forum. The gloves are off. I am going to be brutally honest with you about your question:

Like the rest of your questions, this one is not stupid.

Back to your regularly scheduled programming . . . There ARE situations in cave and technical diving where a diver may briefly be out of gas -- for example, if they screw up a gas switch and switch to the wrong regulator. Most of these situations are manageable, but may require donation until it's sorted out. Having a hose you can restow is an advantage here.

If you have a situation where you have a catastrophic gas loss -- for example, a freeflow, or a dislodged first stage -- you may have someone exiting on significantly less than half their gas. There does exist the possibility that that person may not have enough left after shutting down the offending post, or isolating, to exit the cave. At that point, you are going to have to do some of the exit while gas sharing, and if restrictions are involved, it will be single file.

Suddenly loss of ALL of your gas is virtually impossible. But loss of enough gas that you might have to share to get out is a lot more plausible.

 

[adm3745]

I suppose that if a post failure occured and it took a little while to sort it out, or it was misidentified, you could lose a third of your gas. If the situation caused some panic, the diver could be breathing harder and take alot more gas to get out requiring him/her to tap into your spare third.

In a cave this requires the long hsoe incase of any restrictions + its a ton easier to share air with it.

 

[ucfdiver]

Comment #1- Most OOA situations aren't really OOA situations. This is why we don't do something silly like stuff a long hose where it can't be easily stowed back into place.

I think during gas switches is the most likely time to donate. This is why we pay so much attention to the team during gas switches. Another situation might be a closed isolator valve where the diver breathes one tank empty and panic's (spg would still show full), but it's quickly fixed.

 

[PfcAJ]

Too add to Lynne and James's posts, if your buddy is low on gas and you need to pass a restriction, get them on the long hose first. Running out of gas in a restriction will probably be fatal.

Even if you are in open water, losing a substantial amount of gas can ultimately result in your back gas tanks being empty. The long hose makes gas switches and backgas breaks easier, as it allows some separation between team members.

The long hose affords flexibility in situations where a short hose just doesn't cut it.

 

[nadwidny]

So from my first stupid question, I gather that diving thirds or even more conservatively is all about unexpected things that delay a return to the exit in an overhead environment like silting out, getting lost, that kind of thing.

Several people commented that the likelihood if a team member suffering catastrophic gas loss with manifolded doubles is remote.

So... If the possibility of a catastrophic gas loss is remote...

Why carry a long hose with doubles?

Because the possibility is remote, not impossible.

And unlike Lynne, I think this was a stupid question.

 

[Tortuga68]

Because the possibility is remote, not impossible.

And unlike Lynne, I think this was a stupid question.

"There are no stupid questions... just stupid answers"

 

[DA Aquamaster]

And unlike Lynne, I think this was a stupid question.

The problem with thinking that is that it telegraphs that attitude as well and people then stop asking questions.

There is virtually no value in telling someone "dive a long hose configuration" without thoroughly exlaining "why". If they do it, they then do it without truly understanding the reasons why or the situations where it may be important or useful.

But when someone asks the question, the answers and the discussions around those answers have the potential to help many other divers get beyond the far less than adequate authoritarian reason(s) for doing something.

Now, the real problem is that quality instruction should focus on a critical thinking approach rather than an authoritarian approach to start with, but that is not usually the case. Another "stupid' question would then be "why is that the case?"

 

[Reg Braithwaite]

I'm ok with agreeing that it's a stupid question, I was not joking when I said it was stupid. That being said, I don't have any particular difficulty asking stupid questions, as long as they are not inappropriate. For example, asking certain types of questions in the DIR forum is trolling and inappropriate. So keep calm, carry on!

And thanks for the answers so far, namely:

• Although the posibility of a catastrophic ghas los is remote, the consequences are severe enough that carrying a long hose and enough gas to get a team mate out is worthwhile;
• Various issues can arise where having a temporary gas donation is useful, and;
• A partial donation may be needed if circumstances are such that there is a delayed exit and a team mate doesn't have enough gas to make it all the way home.

 

[Tortuga68]

You could also ask yourself the question Why wouldn't you?