WYDT
Contributor
Great Post Bottomfeeder! I totally agree!!
Gas Sharing in Deco
- Thread starter cadet diver
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
I sometimes run into technical program candidates who have not been taught buddy breathing in their open water class, and so need a bit of 'remedial' work. And my guess is the number of people who are not familiar with the skill will increase... scary is right! However, that said, the actual percentage who've never done it is quite small... now the percentage of people who have not practiced it since open water is very high... that's scary too!
Take care and dive safe
It seems to me that there are two issues here...
(1) Buddy breathing training - I agree that buddy breathing should be a skill that is in the "back pocket" of any competent diver.
(2) Having a plan that requires buddy breathing in the event of the loss of a single decompression tank. Now that's not smart! If you're going to dive a plan where you'll have to share a decompression bottle should you lose one, then, by golly, put two second stages on your decompression bottles!
E. itajara
(1) Buddy breathing training - I agree that buddy breathing should be a skill that is in the "back pocket" of any competent diver.
(2) Having a plan that requires buddy breathing in the event of the loss of a single decompression tank. Now that's not smart! If you're going to dive a plan where you'll have to share a decompression bottle should you lose one, then, by golly, put two second stages on your decompression bottles!
E. itajara
OP
Doppler what I meant was that if you had to buddy breath off the same deco bottle and there was not enough gas to finish your own deco now that you are splitting your supply between you and your buddy.
buddy-breathing a deco bottle?
I guess you can, if there is no other option.
But is there really never any other option?
Let's say you are deco diving and have a 30 minute (total) deco obligation between three or four stops.
You lose a deco bottle for whatever reason.
Ok, you and your buddy now have one deco bottle (instead of two) BUT you also have two sets of BACKGAS!
So why not hand off the long hose from the person who DOES NOT have the problem (the guy WITH the deco bottle) and let him deco on the EXTRA backgas (the guy with the deco bottle doesn't need it!) He can deco on his primary tanks until they get down low enough where he needs the remainder for surface swimming, then use the guy's backgas WITH the deco bottle (he's not using it - he's breathing off the deco bottle.) This keeps the brown stuff factor as low as you can reasonably manage.
The buddy with the deco bottle does the deco on the bottle; the other guy has TWO sources of gas.
Now this means that the guy WITH the gas stays in longer, but that's infinitely preferrable to buddy breathing off a bottle that would otherwise have to be twice the size as really required.
The "oh s$#%" plan is just that - its for those situations. If you add another complication (buddy breathing) to a deco situation, IMHO you're asking for it to get out of control.
You should have enough backgas between the TWO of you to complete the hang on the longer intervals; remember, you do still have ONE good deco bottle between the two of you, and one of you can consume it. The longer hangs won't hurt that guy (assuming we're not talking dangerous PO2s - if we are, then he needs backgas breaks, etc.) If not, then your dive plan is no good; if you can't do the longer hang with two backgas supplies for one diver (the other guy on the deco bottle) then you probably couldn't successfully buddy breathe off the deco gas either and not run out of that.
Is not one of the first credos of rescuing someone in trouble "do not kill/bend yourself in the process"?
What am I missing here?
I guess you can, if there is no other option.
But is there really never any other option?
Let's say you are deco diving and have a 30 minute (total) deco obligation between three or four stops.
You lose a deco bottle for whatever reason.
Ok, you and your buddy now have one deco bottle (instead of two) BUT you also have two sets of BACKGAS!
So why not hand off the long hose from the person who DOES NOT have the problem (the guy WITH the deco bottle) and let him deco on the EXTRA backgas (the guy with the deco bottle doesn't need it!) He can deco on his primary tanks until they get down low enough where he needs the remainder for surface swimming, then use the guy's backgas WITH the deco bottle (he's not using it - he's breathing off the deco bottle.) This keeps the brown stuff factor as low as you can reasonably manage.
The buddy with the deco bottle does the deco on the bottle; the other guy has TWO sources of gas.
Now this means that the guy WITH the gas stays in longer, but that's infinitely preferrable to buddy breathing off a bottle that would otherwise have to be twice the size as really required.
The "oh s$#%" plan is just that - its for those situations. If you add another complication (buddy breathing) to a deco situation, IMHO you're asking for it to get out of control.
You should have enough backgas between the TWO of you to complete the hang on the longer intervals; remember, you do still have ONE good deco bottle between the two of you, and one of you can consume it. The longer hangs won't hurt that guy (assuming we're not talking dangerous PO2s - if we are, then he needs backgas breaks, etc.) If not, then your dive plan is no good; if you can't do the longer hang with two backgas supplies for one diver (the other guy on the deco bottle) then you probably couldn't successfully buddy breathe off the deco gas either and not run out of that.
Is not one of the first credos of rescuing someone in trouble "do not kill/bend yourself in the process"?
What am I missing here?
I don't know about anyone else but when we do a dive with only one decompression gas it isn't a real long dive and we could deco on back gas. I suppose if you wanted to shorten it up a little when the one with deco gas finishes with it he could hand it off. It's nicer to breath it all the way to the surface but oh well.
When our dives require multiple decompression gases the ascent time on back gas alone (all decompression gas lost) would be undoable. It would be hours and hours and even if you had the gas you would likely die of the cold. However, finishing the dive with either of the two decompression gasses would be very doable. What's all this buddy breathing silliness. Remember all the other options. We can swap regs or fix them. We can turn a tank on and off to breath if a reg is free flowing. We can depress the purge to breath if a diaphram is damaged and leaking. If your really worried stage extra tanks.
When our dives require multiple decompression gases the ascent time on back gas alone (all decompression gas lost) would be undoable. It would be hours and hours and even if you had the gas you would likely die of the cold. However, finishing the dive with either of the two decompression gasses would be very doable. What's all this buddy breathing silliness. Remember all the other options. We can swap regs or fix them. We can turn a tank on and off to breath if a reg is free flowing. We can depress the purge to breath if a diaphram is damaged and leaking. If your really worried stage extra tanks.
Bingo.
Rick
- Messages
- 3,464
- Reaction score
- 12
Its just another option, one that it appears many people don't know how to do. Its not a first choice but, assuming you know how, it is an option.
Of course you can deco out on backgas or on backgas plus one gas when 2 were planned. Figure half-again your time in the water or so, more if on backgas with 2 gases lost.
Buddy breath the gas one guy has lost, figure original scheduled time at stop.
Why is that "silliness"?
WW
I guess I called it silliness for a couple of reasons. First, I don't think it should come to that given that we plan for lost gas and will most likely have better options. Second, The fact that not all OW divers are tought buddy breathing shouldn't account for someone doing a "technical dive" not being able to do it should they decide it's needed. IMO, Anyone doing a dive requireing a significant decompression obligation (or any other overhead) should be prepared to use any one of a number emergency procedures most or all of which IMO, would be better than buddy breathing. I do agree though that if the dive gets real bad you do whatever it takes.
- Messages
- 3,464
- Reaction score
- 12
You're right, it obviously shouldn't come to that but as you know when things get sideways they have a way of getting extremely sideways in a big hurry.
I think with the relative ease that divers can become "technical" today there are probably a large number of certified tech divers who have never done it, after all its been optional in o/w for a good number of years (what percentage of instructors do you think teach it?). It wasn't covered in a my of my higher level classes.
I think most consciencious instructors still teach it, I think most lazy instructors don't.
Personally I feel that its an excellent skill, a last resort yes but one that can remove one's bacon from the fire! It saved mine once about 20 years ago.....
WW
Similar threads
