transferring scuba regulator from tank to tank underwater?

[Scared Silly]

Boy Matt, I would to suggest that you think outside the kiddie pool. There are many on the board who do technical diving where one can not just abort the dive and surface either due a physical or virtual overhead. What you are failing to understand that excrement happens and rarely it is just just a single event that leads to a complete cluster fuk.

You want an example. Diving a wreck which you decided to penetrate. You are diving doubles and are a couple levels down in the engine room. Darwin the dork diver your buddy comes along a slits the crap out of the room. He panics and ditches you in the dark. You can not see more than 6" in front your face. Trying to find an exit you hit an old beam that shears both of your regs so that they are both leaking copious amounts of air. You get one post closed down as well as the isolator but you can not shut the other post cause that is your source. You can not find an exit cause of all the silt. You have a deco bottle but it is 100% O2 and you are 100 feet so breathing it would probably lead to O2 toxicity. So what do you do?

Me I would take my rig off take off the trashed reg and replace it with my deco reg. Then shut down the other damaged reg. At that point I have preserved all of my gas and breathing off a good reg. At that point I can continue looking for the exit.

 

[halocline]

I think in my first post I told of a friend that had this happen.
He was doing a technical dive, with a lot of deco. When he made it to his 20 foot stop and turned on the O2 the O-ring on the DIN fitting blew out.

Now, he could have done his deco on back gas, however when your in 40 degree water and you have an hour of deco on back gas, you prefer not to do that. Switching the regs from is 50% cylinder onto the O2 cylinder was a good option. It allowed him to deco in a timely manor and get out of the water.

Would a recreational diver ever run into this situation, no.

Right, switching regs on a deco bottle while you have backgas to breathe is a perfectly reasonable scenario, but that's not what the original situation was postulated as.

 

[halocline]

You want an example. Diving a wreck which you decided to penetrate. You are diving doubles and are a couple levels down in the engine room. Darwin the dork diver your buddy comes along a slits the crap out of the room. He panics and ditches you in the dark. You can not see more than 6" in front your face. Trying to find an exit you hit an old beam that shears both of your regs so that they are both leaking copious amounts of air. You get one post closed down as well as the isolator but you can not shut the other post cause that is your source. You can not find an exit cause of all the silt. You have a deco bottle but it is 100% O2 and you are 100 feet so breathing it would probably lead to O2 toxicity. So what do you do?

Who's "thinking in the kiddie pool"?

 

[Tortuga68]

Right, switching regs on a deco bottle while you have backgas to breathe is a perfectly reasonable scenario, but that's not what the original situation was postulated as.

I don't agree; the OP mentioned swapping between two tanks, he didn't say that there were only two tanks available

...if the scenario is to discuss how to dive safely and "come back from the dive alive" then it's a stupid question, because the real answer is you would never be in that situation, and you could easily explain how to dive in a manner that would prevent it. That's what safe diving is

Is it only me that gets the ****s when someone's answer to a hypothetical situation is "well that would/should never happen"? What I'd like to hear is what you could do if it does happen, it's probably what I enjoy most about SB

 

[halocline]

Is it only me that gets the ****s when someone's answer to a hypothetical situation is "well that would/should never happen"? What I'd like to hear is what you could do if it does happen, it's probably what I enjoy most about SB

People construct solutions to hypothetical situations that don't actually exist from time to time on this board. It is interesting for conversation, but if I remember the original post was an instructor asking a student how he/she would handle a hypothetical situation in order to dive safely, and that situation simply could not realistically happen if the diver was following any sort of safe diving practice. It assumes that the student is diving unsafely to begin with, and I don't think that's good teaching. So, in terms of a discussion about safe diving, these sorts of things are IMO not useful, especially when they involve equipment decisions. It's kind of like the old argument about balanced 1st stages being "safer" than unbalanced because they will breathe better at depth when the tank is very low. It usually starts something like "if you were at 120ft with 300 PSI in your tank, a balanced reg will allow you get enough air easily..." or a similar scenario. The 'best' answer to that scenario is "what are you doing at 120 ft with 300 PSI and no other air source?" not "use a better reg"

I realize that occasionally divers find themselves in situations that they would prefer not be in, or have lapses in judgment, (I'm no exception, and I don't claim to be) or have unexpected gear failure. But constructing scenarios that are not realistic, and then formulating policies on how to handle them, is just not useful IMO, or even enjoyable. I'd rather discuss the value of the hypothetical to represent an actual possibility in diving.

Another one that has come up is in the manifold vs independent doubles argument. A tech diver once argued on this board that independent doubles were "safer" for obstruction diving because the isolator could get destroyed by an impact and then all the gas would disappear. Theoretically this is "true" although the likelihood of it happening is FAR lower than the likelihood of reg failure, even subsequent reg failures on both tanks, and the isolator provides additional safety (more gas) in the case of reg failure.

 

[tregrrr]

People construct solutions to hypothetical situations that don't actually exist from time to time on this board. It is interesting for conversation, but if I remember the original post was an instructor asking a student how he/she would handle a hypothetical situation in order to dive safely, and that situation simply could not realistically happen if the diver was following any sort of safe diving practice. It assumes that the student is diving unsafely to begin with, and I don't think that's good teaching. So, in terms of a discussion about safe diving, these sorts of things are IMO not useful, especially when they involve equipment decisions.

you ever think that something posted in the "advanced Scuba Discussion" forum may in fact attract attention from divers who are curious about more advanced and **GASP** technical diving??

Now i understand that in your warm, clear, 60' deep (if you dig down in the soft sand), ocean devoid of entanglements, wrecks or alluring 'light zone' caverns, any possibility of not being able to directly access the surface might be scary and considered dangerous. Get over yourself. This section of SB is aimed at divers who know there is more out there and are interested in finding out something about it. Do not let your own personal bias as to what is safe and unsafe, plausible or implausible, hypothetical or fantastical cloud over other people's curiosity.

Would you think that it might better suit the community to have discussions where information is freely transferred or where people cannot ask the questions that come to mind?? What we have here is an opportunity for people to sate their thirst for understanding without putting life, limb or expensive dive gear at risk.

I realize that occasionally divers find themselves in situations that they would prefer not be in, or have lapses in judgment, (I'm no exception, and I don't claim to be) or have unexpected gear failure. But constructing scenarios that are not realistic, and then formulating policies on how to handle them, is just not useful IMO, or even enjoyable. I'd rather discuss the value of the hypothetical to represent an actual possibility in diving.

so leave. Nothing is actually stopping you from clicking the link to go back to the forum and choose another thread read. If you aren't having fun, then go diving or do something that you do consider fun. I am sure you could even find some pencils that need sharpening. I for one find it interesting to see how people think and come to their conclusions and what lines of logic THEY follow.

So go loosen up the restrictive clothing you are wearing, and have a little fun, however you may derive it.

 

[olphart]

If the situation is that dire, you could always remove the bad reg and crack the valve just enough to freeflow breathe all the way to the surface. You have to do it in training and it wouldn't be that much more difficult to do w/o a reg on the bottle.
Before I was shown how it was done, I assumed you did a freeflow breathing by holding the mouthpiece completely out of your mouth and sipped the bubbles, just the way Mike Nelson did on one of his episodes. (Yes I'm that old) It didn't seem all that hard to me.

 

[miketsp]

All I know is back in 1973 when my wife and I got our basic (NASDS) certification, one of the exercises we did in the pool was to change a regulator on and off a tank while buddy breathing.
Glad it was a rental regulator. We got our own regulators before our checkout dive.

In 2002 while doing a CMAS course, mounting a regulator UW onto a cylinder was part of the training. I don't honestly remember if there was an SPG on the reg set or not but I'm pretty sure there was.
This was done in the pool with FW and Scubapro regs.

 

[RonFrank]

This maybe an interesting theoretical debate, and I guess a couple of responses have indicated that this has been done.. but...

1) I have never run out of air. DD can tell you it can happen, but it's hardly normal.

2) What are the odds of tank A running out or air while take B has a reg malfunction? And what are we diving here, independent doubles? That in it's self is a bit unlikely.

3) Most important in all this debate, where is your buddy?

In response to Scared Silly's theoretical situation, what do you do? You die.

Let's face it, if you have that many things going wrong, maybe your time is up. I for one doubt many divers could keep their head in a Zero vis environment while having both hoses slashed, and tanks emptying in a matter of seconds.

However this question has been asked, and answered before, and the short answer is "YES".

 

[tregrrr]

Just remember you have the entire rest of your life to figure out a solution to any jams you get yourself into while diving. How long that life will be is completely up to you.