Drop your weights or not...

[LeadTurn_SD]

Thanks John and bleeb for your posts explaining CESA a little more clearly.

CESA's or ESA's have been performed from depths WELL below recreational depths (below 130'), with the diver surfacing unharmed. It is important to understand that this carries many risks, but it is equally important to know that it can be done. The knowledge that a healthy diver can reach the surface and survive even from deeper recreational depths should be "owned" by every diver.

Early training emhasized this more than current training I think (I know this varies with the instructor).

Highest marks for teaching your students a bit more than the standard course calls for.

Best wishes.

 

[Ripple in still water]

Found my PADI OW manual, copyright 1999. At page 158, it says that if you are OOA "and the water is 30 to 40 feet deep or less, you may decide to make a CESA." On the next page it says that if you are too deep for a CESA, you need to make a buoyant emergency ascent. I recall my instructor stating about the same thing.

If indeed one should always be able to CESA, unless PADI's changed its standards, there are tens of thousands of divers getting recklessly-bad advice. And even if PADI did change its standards, I (and I trust tens of thousands of other divers) didn't get the memo.

I'm not claiming that because PADI says it it's true, and I come to SB to learn from (the many) folks who know more about diving than me, but there's a pretty big disparity here.

 

[xyrandomyx]

I have a more recent copy of the PADI OW manual (copyright 2008). The 'Running low on or out of air' section is also on page 158 in my copy.

It does mention that a normal ascent might be possible if you're very low on air because more air in your cylinder becomes breathable as surrounding pressure decreases. It doesn't say anything about getting a breath out of a cylinder when shallower if you're completely out of air and it doesn't say anything about trying to get air out of an apparently-empty cylinder during a CESA. I suppose that could be inferred from what it does say about more air becoming breathable as you get shallower, but it's not stated explicitly.

As for CESA depth, my copy is even more conservative: it says '...and the water is 6 to 9 metres/ 20 to 30 feet deep or less, you may decide to make a controlled emergency swimming ascent'.

It doesn't seem to me that just because people have managed a CESA from deeper than 40m/ 130' that it's always possible -- how many have attempted a CESA from that depth or even less and not survived? I wouldn't know, but I think it's clear that the deeper you are, the less likely you would be to succeed. It'd also depend on the diver's physical fitness and other physiological factors. The chances of success would also depend on the situation: if a diver's out of air after fighting against current, already somewhat tired and starting to panic, I'm sure they'd have less chance of pulling off a CESA from significant depth.

So, I'd imagine the reasoning for PADI's guidelines are something like this: almost all divers in almost all situations should be able to successfully perform a CESA from 9m/ 30'. Deeper than that and some divers or some divers in certain situations may not be able to. So, following the often-repeated 'you can fix bent but you can't fixed drowned' adage, they recommend a buoyant ascent from anything deeper than that.

That said, I'm glad I was told they you might be able to get a breath off an apparently-empty cylinder as you get shallower. And, I'm glad I was told that a CESA is possible from greater depths (we had a navy diver doing his DM course while I was doing my OW course, he told us they did CESA drills from 30m/ 100' in the navy). But, I can guess at the reasons for PADI's guidelines.

 

[Bob DBF]

May be the big over-site in this conversation is your thought processes when the event happens. If you panic you screw the pooch, end of story. On the other side is being so methodical that you involve yourself in procedures and forget about the time limit and miss your chance at the last ditch solution.

I was free diving and was grabbed by kelp, no big deal just drop a foot and let the surge untangle and go. It didn't work, I reached around, it was on my back and I loosened it and started back up. It didn't work, I started for my knife figuring I'd cut loose. The surface was 10 feet away and I figured 15 seconds may be more before blackout. At that point I thought screw the knife and drop the weight belt, I'll be the only diver on the north coast who died with his weight belt off, and I might have time to use the knife if this doesn't work. I dropped the belt and broke free and laid on the surface wondering if I would ever dive again.

Point being, if I had not broken the train of thought early enough to use a last ditch effort, I could have passed out with the knife in my hand.

And this was after decades of weight belt abuse. Before taking my gear off after a beach dive I will dump my weight belt as if I were dropping it in the water. This makes sure my hand goes to the belt and the belt drops free. I go through belts faster but I know it will work right when the time comes.

Yes, I still dive both SCUBA and free but I will quit earlier when things are not quite right.



Bob
--------------------------------------
I may be old, but I’m not dead yet.

"the future is uncertain and the end is always near"
Jim Morrison

 

[boulderjohn]

We had a thread that included the PADI wording for this about a year ago. I was surprised by the wording cited and asked PADI about it. I was informed that the wording about the difference between CESA and buoyant ascent depths was changed in the most recent handbook because of a recognition of the implication that the wording implied that the CESA could only be performed from relatively shallow depths. I do not have the current wording with me.

 

[The Light Eternal]

I like Ken's idea of doing the CESA with weight belt in hand. I'd rather have DCS than be dead. I wouldn't do a buoyant ascent first but having it available in the event I become unconcious seems like a good compromise.

 

[Rich Keller]

I think everyone agrees with that.

The discussion is trying to determine when it is called for.

Let's go to one extreme: You are at 60 feet. You look at your gauge and see you have only 400PSI left. Do you drop your weights? I am guessing we would all agree it was not called for in that situation.

Let's go to another extreme: You are almost OOA at 100 feet. Your BCD is not working, so you can't get any lift from it. You feel a heart attack starting and worry that you will pass out. Is dropping weights called for? I think everyone here would vote yes.

Now, where so we draw the line?

The original guestion was "Were you trained to drop your weights in an emergency?" My answer is what I was trained to do. There seems to be a stigma attached to droping your weights and when it comes down to that point only one person knows best. The point I was trying to make was NOT to worry what anyone else might think or say, YOU are the one who knows best in that moment.

 

[boulderjohn]

The original guestion was "Were you trained to drop your weights in an emergency?" My answer is what I was trained to do. There seems to be a stigma attached to droping your weights and when it comes down to that point only one person knows best. The point I was trying to make was NOT to worry what anyone else might think or say, YOU are the one who knows best in that moment.

I guess then, the question really is this: what constitutes an emergency worthy of dropping the weights?

Are you suggesting there is a peer pressure of some kind pushing divers to keep their weights when the emergency is dire enough to require their release?

Can you describe you vision of the dividing line between when you (using your personal judgment) would keep your weights and when you (using your own personal judgment) would release them in a heartbeat?

EDIT: What I guess I am really saying is that we agree that the weights should be dropped without hesitation when it is appropriate to drop the weights. What is not clear to me is when you think that moment has arrived.

 

[Rich Keller]

I guess then, the question really is this: what constitutes an emergency worthy of dropping the weights?

Are you suggesting there is a peer pressure of some kind pushing divers to keep their weights when the emergency is dire enough to require their release?

Can you describe you vision of the dividing line between when you (using your personal judgment) would keep your weights and when you (using your own personal judgment) would release them in a heartbeat?

EDIT: What I guess I am really saying is that we agree that the weights should be dropped without hesitation when it is appropriate to drop the weights. What is not clear to me is when you think that moment has arrived.

I do not think I could come up with a list of when is the right time or not, there are just too many variables involved. I would say that if you think it is the right thing to do then do not hesitate. If you are not sure then I would not waist what little time you may have thinking about it and drop the weights. It all comes down to your personal experience and the amount of time you have in the water. I am not however suggesting you drop your weights at the first sign of trouble either as I believe the first rule of diving is "If you panic, you die." In the end you are the only judge of what is best not me or anyone else. One last thought that I left out before. I do not over weight myself and use the BC to descend, I am neutral at the surface with the BC empty, so if I do have to drop I am not shouting to the surface like a rocket. This will also allow you to depend less on your BC and for shallow dives you may not need to make any adjustments to it at all.

 

[dumpsterDiver]

I do not think I could come up with a list of when is the right time or not, there are just too many variables involved. I would say that if you think it is the right thing to do then do not hesitate. If you are not sure then I would not waist what little time you may have thinking about it and drop the weights. It all comes down to your personal experience and the amount of time you have in the water. I am not however suggesting you drop your weights at the first sign of trouble either as I believe the first rule of diving is "If you panic, you die." In the end you are the only judge of what is best not me or anyone else. One last thought that I left out before. I do not over weight myself and use the BC to descend, I am neutral at the surface with the BC empty, so if I do have to drop I am not shouting to the surface like a rocket. This will also allow you to depend less on your BC and for shallow dives you may not need to make any adjustments to it at all.

Exactly, you shouldn't be thinking about dropping your weights for very long. Either you KNOW you don't need to ditch them or ..they are gone. I myself have never ditched a belt in 35 years of scuba diving, but it is important to NOT think of dropping lead as a LAST resort. It should be on the short list of potential responses..

Also, the type of exposure protection and quantity of lead makes a huge difference. Dropping a 10-12 lb belt underwater is nothing like dropping 25-28 lbs of lead, so making general statements is impossible.