Overhead environments and open water scuba divers

[tstormdiver]

As I said in the original post, the easy answer is "no overhead environments without training". But that isn't what happens, out there in the real world. People go dive the Cathedrals, or do swim-throughs in Cozumel. I swam through the bow portion of the Rhone as an OW diver, and I'd have a hard time telling someone that that's a completely unsafe thing to do, although if somebody panicked in there and tried to bolt, they'd be in a world of hurt.

I think some environments are more benign than others -- multiple exits, coarse sediments, lots of ambient light, minimal distance of penetration. Your idea about not carrying lights isn't a bad one, since all of the "benign" places I can think that I've been were easily dived without a light.

No overhead without training may be the easy answer, but in light of what has been happening recently, what other real options is there to minimize the risks?

 

[DaleC]

I'll play devils advocate for a moment and say that falling back on the "get formal training" refrain does carry some false optimism. As stated, a simple overhead course only takes a day or two but I question what can really be instilled and retained in that short of time. To me, when I look at those types of fatalities I see the primary causal factor being lack of discretion. This is an internal trait that can be re-enforced via training but can also be negated as well. Someone who lacks it is just as likely to enter an overhead because they now have the certification to do so, even though they lack the skill/knowledge.

Not knocking training, because it's valuable when correctly applied, but discretion. humility and the ability to say no to ourselves and others would go much further to reduce accidents of this nature IMO.

 

[boulderjohn]

On the theme of not knowing what the danger is if you don't have the training....

When I was doing my cave training, at one point in the dive my instructor started down a wrong passage. It was a situation where the correct passage was not obvious, and he was testing me. I had to stare long and hard at the situation to be sure he was wrong, and then signal him with my light to bring him back. Being a student who was on the alert of that sort of thing made me more aware than another diver might be. As an inexperienced diver going with a friend into a cave, I might have followed that leader to our mutual doom.

In a recent death in Ginnie Springs in which an OW certified diver was found in a very confusing place in the cave system, the best conjecture as to what he as doing there was that he meant to just go in and out the cavern area but got confused and took a wrong turn. In that location, it would have been an easy mistake to make. Once he had taken that wrong turn, he was lost.

 

[jmneill]

Your idea about not carrying lights isn't a bad one, since all of the "benign" places I can think that I've been were easily dived without a light.
[/QUOTE]

The problem with this is that these "benign" (or at least the ones I have dove and consider to be benign) places become substantially less enjoyable without a light. (or not enjoyable at all)

 

[Lorenzoid]

Great set of guidelines. Unfortunately, the divers who dive where they shouldn't are not typically the ones who regularly read SB or any other serious source of diving information.

I've never felt comfortable with those swim-thrus in Cozumel, for example, yet I've always gone along with the group and never spoken up. That kind of swim-thru violates at least your principle of the passage having enough room for two divers side by side. If someone gets stuck in there, it might be minutes before the DM notices the missing diver. Meanwhile, the divers in the queue behind the missing diver waiting to enter the swim-thru and (often stumbling over each other near the entrance) might wonder what's going on, maybe panic, maybe try to swim around the coral head to attempt to rejoin the group on the other side and end up getting lost, etc. It's occurred to me that some of those relatively benign swim-thrus are not appropriate for a group of vacation divers being led by a single DM, as is often the case. Not to pick on Cozumel, but that's what came to mind based on my own dive experiences.

 

[flots am]

This thread is prompted by a number of accidents, but the most recent was yesterday, when four people died in a sea cave in Italy, because they followed a guide into an environment where they didn't have the training to cope with the complications that ensued.

This is not a diatribe about "don't dive in any overhead environments without appropriate training." That's an easy answer, but it isn't the reality of what people actually DO out there.

It should be. If OW divers would listen to the above, fewer would die. Right around the last class session, I explain the "use of the middle finger underwater," "ending the dive without the DM" and "how to not tip" when interacting with dive guides and DMs who want to go places and do things that are not inappropriate.

Some folks make light of "Yer gonna die!", but the truth is that OW training does not teach procedures for zero-viz or overhead dives, and any OW divers that enter overheads are simply spinning the wheel and hoping for a good outcome. While it's nice to say "a silty bottom is dangerous," and "currents may be unpredictable", the divers would typically have no idea if the bottom was silty until it's too late.

flots.

 

[jmneill]

It should be. If OW divers would listen to the above, fewer would die. Right around the last class session, I explain the "use of the middle finger underwater," "ending the dive without the DM" and "how to not tip" when interacting with dive guides and DMs who want to go places and do things that are not inappropriate.

Some folks make light of "Yer gonna die!", but the truth is that OW training does not teach procedures for zero-viz or overhead dives, and any OW divers that enter overheads are simply spinning the wheel and hoping for a good outcome. While it's nice to say "a silty bottom is dangerous," and "currents may be unpredictable", the divers would typically have no idea if the bottom was silty until it's too late.

flots.

What about the overhead dives where it is well known in advance that there is no silty bottom to stur up? I hate seeing this broad, accross the board stroke against all OW divers in ANY overhead environment. I wish I had the time to start a list of dive sites, public and private involving overhead (non cave) with excellent to stellar safety records. I'll bet, with a little research it would be the longest post in this thread.

 

[tstormdiver]

What about the overhead dives where it is well known in advance that there is no silty bottom to stur up? I hate seeing this broad, accross the board stroke against all OW divers in ANY overhead environment. I wish I had the time to start a list of dive sites, public and private involving overhead (non cave) with excellent to stellar safety records. I'll bet, with a little research it would be the longest post in this thread.

I think the point of this thread is when/ where does an overhead environment become dangerous to an Open Water diver with no training? & how does one determine that danger without ending up a statistic? Penetrating 1 ft? 10 ft? 100ft? 1000ft? When is it too silty? A dusting? 1/16"?, 1/8"?, 1/4"?,...... What type of silt? Gravel? sand? mud? clay? Mung? Stability of the overhead environment? While, as you say, "many places have a stellar safety record", does that really mean it is safe? Or have they just been lucky so far? With the exception in a course environment (where there are still risks, but minimized) with a well trained, attentive instuructor, I tend to side with flotsam in that any time a diver goes outside of their training, they are loading 1 bullet into the revolver, free spinning the chamber, pulling back the hammer, pointing the gun at their temple & pulling the trigger. Will it land on the "one" slot with the bullet? or will you get lucky?

 

[ianr33]

I think the real problem is that on the way in the average OW diver really doesn't have a clue if it's a safe environment or not.
As an example, an OW diver going to the back of the cavern in Jackson Blue would most likely be just fine. (Although I in NO WAY would suggest they do that) There is normally flow,often lots of flow.The bottom is rock and it's essentially impossible to silt it out.
Put the same diver in Hole in the Wall though and he's on borrowed time. No flow,masses of silt and the way out is not at all obvious without a line.

I doubt the unfortunate deceased divers in Italy were carefully assessing the flow and whether the bottom was sand or clay. It really is a case of you don't know what you don't know.

 

[jmneill]

I think the point of this thread is when/ where does an overhead environment become dangerous to an Open Water diver with no training? & how does one determine that danger without ending up a statistic? Penetrating 1 ft? 10 ft? 100ft? 1000ft? When is it too silty? A dusting? 1/16"?, 1/8"?, 1/4"?,...... What type of silt? Gravel? sand? mud? clay? Mung? Stability of the overhead environment? While, as you say, "many places have a stellar safety record", does that really mean it is safe? Or have they just been lucky so far? With the exception in a course environment (where there are still risks, but minimized) with a well trained, attentive instuructor, I tend to side with flotsam in that any time a diver goes outside of their training, they are loading 1 bullet into the revolver, free spinning the chamber, pulling back the hammer, pointing the gun at their temple & pulling the trigger. Will it land on the "one" slot with the bullet? or will you get lucky?

Comparing the average OW diver, in the average overhead environment you would normaly find said diver, to a one in six shot of death is rediculous. I think your revolver would need to hold several hundred thousand rounds for this to be a good analogy.