Thoughts on Deep and Wreck Diving

[jtivat]

As for solo dives, we say "every dive is a solo dive," and "if you can't save yourself you can't save me." We don't have DIR teams but you can put most of us together quickly with a mission or goal and we will jell and the job will get done.

Pete J

That sums it up, if you would not do the dive solo then I don't want to do the dive with you.

 

[limeyx]

I think a lot of us are familiar with rock bottom. How do you factor in more than 1 gas? You are not making a direct ascent to the surface in decompression diving. It doesn't account for deco gas either, at least Lamont's original post doesn't.

Rockbottom is the min amount of gas you need to get to the "next available gas" so either

1) the surface
2) the next gas switch.
on a tech1 dive, it would be the min amount of gas needed to get 2 divers (one OOA) to 70 feet (since we use 50% nitrox as deco)

You can then pad it if you need additional gas to cope with a lost deco gas situation.

 

[TheRedHead]

That sums it up, if you would not do the dive solo then I don't want to do the dive with you.

I can't understand this point of view. I don't see my buddy as a liability.

 

[limeyx]

With regards to solo vs buddy in techdiving. Once you go deep enough or penetrate far enough, trying to rescue someone means that you become another victim. To make a rescue feasible on those kinds of dives would require an "unreal" amount of gas. AFAIK even "DIR gods" do those kinds of dives that way.
...

Not so. Look at the incredible amount of safety planning done by say the WKPP.
There is always planning for a certain amount of gas loss/failure.
In Wakulla I think they stage enough safety gas for if one rebreather fails and they have to scooter out on open circuit. The EKPP take double rebreathers in because they simply cannot stash enough gas in the cave due to logistics.

I'm not sure how the WKPP plans Turner sink diving, but even reading the dive reports scares the heck out of me for that one.

But yes, you can only plan for so much. If two RB's were to go out, or all the scooters to die then you would indeed need incredible amounts of gas and so you have to balance the risks.

 

[Gilldiver]

Rockbottom is the min amount of gas you need to get to the "next available gas" so either

1) the surface
2) the next gas switch.
on a tech1 dive, it would be the min amount of gas needed to get 2 divers (one OOA) to 70 feet (since we use 50% nitrox as deco)

You can then pad it if you need additional gas to cope with a lost deco gas situation.

One thing to keep in mind is that when the crap is flowing you can bail out on your deco gas at about twice the MOD. So if your next gas is 50% you or your buddy can go on it at 140. Why, because #1) Any gas is better then water #2) you both should be hauling *** to the next DECO gas stop and your pO2 is falling fast as you assend. Of course this is much more applicable to open water wreck then it is to cave.

When can this happen - Say your buddy got into a net at depth or one of you has something fall on you inside a wreck, it takes both of you 10 minutes to cut him out or get out. His SAC is way up and yours is not much better. You both may low on gas by the time you are going up. In this case you blow off the deep stops and get up to the next gas ASAP.

This has happend to many, and may happen to you if you stay in the sport long enough.

Pete J

 

[limeyx]

One thing to keep in mind is that when the crap is flowing you can bail out on your deco gas at about twice the MOD. So if your next gas is 50% you or your buddy can go on it at 140. Why, because #1) Any gas is better then water #2) you both should be hauling *** to the next DECO gas stop and your pO2 is falling fast as you assend. Of course this is much more applicable to open water wreck then it is to cave.

When can this happen - Say your buddy got into a net at depth or one of you has something fall on you inside a wreck, it takes both of you 10 minutes to cut him out or get out. His SAC is way up and yours is not much better. You both may low on gas by the time you are going up. In this case you blow off the deep stops and get up to the next gas ASAP.

This has happend to many, and may happen to you if you stay in the sport long enough.

Pete J

Well, i'd say it's highly not recommended (PPO2 of 3.x is going to probably knock you out real quick) but yes I admit better than trying to breathe water. However, if your buddy has really been breathing hard, maybe you have some backgas spare for them since you were breathing less hard?

In the end, it's about knowing what assumptions you made about failures. Once you exceed those assumptions, then you may not have enough gas and you have to consider things like the above.

 

[Gilldiver]

That sums it up, if you would not do the dive solo then I don't want to do the dive with you.

That is not quite what I meant. I meant that you have to be prepared to get out of a problem by yourself. You can not count on a buddy pulling you out. If he is there, fine it helps - a lot. But if he is not, what then? I just can't assume that you can save me, if you can't save yourself.



The DIR option #1 has always been around. The worst thing you could ever say about a wreck diver is "I wouldn't dive with him." That is why the core was, and still is, very tight. We know what each of us can, and can not, do from long history. We can all call the dive on the boat or in the water and no one will ever say a thing about it. We know if one of us called the dive, it was the best thing to do for that person.



Can you take your tanks off and get the net or mono ball off the regs and valve? How about that pesky 30' of stainless leader and set of three triple hooks you just ran into and are now hooked into your suit, if not the flesh of your arm? If you are swimming around and all of a sudden your legs are wrapped up in mono, what do you do? Do you panic and thrash around or do you get mad and slowly and carefully start to cut yourself out?



Where is your panic zone and can you hit it and come back from it to say "I'm going home today, so how do I get out of this?"



The DIR team approach is great - but teams are the hardest thing to keep together. You may find that out as you and your team get older and all of life’s other things get in the way of diving.



Pete J

 

[Gilldiver]

Well, i'd say it's highly not recommended (PPO2 of 3.x is going to probably knock you out real quick) but yes I admit better than trying to breathe water. However, if your buddy has really been breathing hard, maybe you have some backgas spare for them since you were breathing less hard?

In the end, it's about knowing what assumptions you made about failures. Once you exceed those assumptions, then you may not have enough gas and you have to consider things like the above.

There have been a number of cases where a diver has died on the bottom with empty back tanks and had full stages. The question is, did he die before he had a chance to switch, or did he die because he was afraide to go on the stages and haul *****?

 

[PerroneFord]

There have been a number of cases where a diver has died on the bottom with empty back tanks and had full stages. The question is, did he die before he had a chance to switch, or did he die because he was afraide to go on the stages and haul *****?

Thats interesting. Usually you'd breathe the stages first...

 

[JeffG]

Thats interesting. Usually you'd breathe the stages first...

He meant deco tanks.