CESA Question

[armeyer82]

One buddy bring the unconscious person.

The third person try to follow the two others and provide assistance if needed but mostly trying to not be in the way?

That makes sense, but what if the third person isn't able to see to follow and is not comfortable performing a CESA?

 

[BlueTrin]

That makes sense, but what if the third person isn't able to see to follow and is not comfortable performing a CESA?

Sorry I think there is a misunderstanding here: CESA is not done as a team, this is valid for two people as well.

If someone is unconscious, you do a controlled buoyant lift (in bsac terminology), not a CESA.

Since a CBL is not a CESA, I think it possibly answers your question already, because a CBL is much slower than a CESA.

But if the third guy just wants to ascend on his own, well … you still need to bring your unconscious buddy, so you do that.

He does whatever he can/want then and you just focus on saving the unconscious diver … but always within the limit of risks you are comfortable with: I.e. you are never under obligation to risk your own life to save someone.

 

[dmaziuk]

That makes sense, but what if the third person isn't able to see to follow and is not comfortable performing a CESA?

Then you all shouldn't have been diving. You don't do CESA until you run out of gas. If you have a team of 3 with one diver unconscious and 2 OOG, You're Doing It Wrong(tm).

 

[60plus]

There is one certainty - if you have no air source and stay underwater you will die. A local PADI instructor (to the consternation of a number of other instructors) teaches that getting to the surface however fast is by a wide margin the lesser of two evils. On recreational dives a fast ascent is unlikely to result in injury so long as you slowly breathe out. Trying to fin to catch an inattentive buddy then realising you are not going to catch them is probably worse than a rapid ascent. Others on here will question what I am going to say next. If I was in a no alternate air source situation I would ascend breathing a little using my inflator hose as a counterlung. These situations should never happen if good buddying practice is followed. However if you are finning against a current and your buddy's mind is on that it can be surprisingly hard to catch up. Never get out of a quick reach of your buddy.

 

[Belzelbub]

A local PADI instructor (to the consternation of a number of other instructors) teaches that getting to the surface however fast is by a wide margin the lesser of two evils.

Strange that that gets consternation. I was taught that in dire emergencies, it is preferable to deal with it at the surface. At least there you have options. Not saying bolt to the surface at the first issue, but if all else fails, getting to the surface is preferable to staying submerged permanently.

 

[pauldw]

It's not just the total nitrogen in your body that causes illness. When at depth, the pressurized gas you breath remains stable and in solution in your blood. When you ascend too quickly, that gas can bubble out of solution from your blood. Imagine you have a bottle of pop and you shake it. With the cap still on, the carbonation is under pressure and it looks fine. But when you twist the cap off, and the ambient pressure drops quickly, not so stable anymore.

This is the part of my OW class I still remember many years later: the instructor very, very slowly (over minutes) opening a bottle of pop, and rapidly opening another. One bottle: no bubbles. The other bottle: a lot of bubbles. Didn't require much thinking to figure out which kind of fluid we wanted our blood to be like.

 

[pauldw]

My mind is blown.

Pay attention to this thread so it isn't your lungs!

 

[60plus]

Just thought I would add, although I do not know for certain, is that when the instructor makes that statement he is probably referring to OW depths <20m and maybe not much more. Also he is probably thinking of inexperienced divers who are more likely to mess up OOA procedure and in their case breathing out whilst heading for the surface is the best option.
Not relevant to modern recreational diving but when my father learnt to dive for dock work in the 1930s the initial assessment before training proper was that the trainee should be able to hold their breath for 3 minutes, freedive to 75 ft and do what is now called CESA from 75 ft. This was done in a tall tank about 15 ft diameter with viewing windows and rescue divers on hand. It would be in the early 1960s when my father and some friends used to jump off the dam and go to the bottom of Wet Sleddale reservoir. The dam is 21m high and they used to hold a stone in each hand to get down quickly.

 

[Nosmosis]

I became a certified PADI Open Water Diver yesterday. In Puget Sound. In December. Headed for Cozumel next month. Go me!

PADI says the Controlled Emergency Swimming Assent should not be used from depths greater than 30 feet. This raises some questions in my mind. First, just exactly what is someone supposed to do if they run out of air at 100 feet of depth and an alternate air source is not available? I guess the only alternative to dying would be to exceed the safe assent rate and just get to the surface. Am I missing something here?

I also know that running out of air does not just happen by accident. It should never happen.

Here is another curiosity: What do free divers do? We've got a free diving depth record of more than 800 feet. Do free divers hold their breath until they actually return to the surface several minutes later? Are they not risking decompression sickness?

Thank you, in advance, for considering my questions.

Instead of learning CESA, you can learn to dive in a team and plan your gas.

 

[wetb4igetinthewater]

Instead of learning CESA, you can learn to dive in a team and plan your gas.

that's pretty much true of every topic!