On my last dive to 400 Ft...

[lamont]

And you're absolutely right about that. I mentioned paranoid narcosis, but a CO2 hit would be just as bad. You can elect not to swim through and swim over. I would do that if I didn't feel right about the dive or even thumb the dive if I didn't feel good about it. You do have to use common sense in all diving, particularly deep dives.

I'd be more worried about someone in front of me taking the CO2 hit and trying to get back out through me, though....

 

[Jason B]

...unless you can provide some real statistics about real accidents involving dives people make on a regular basis. I've read Exley's books on cave diving and I dive with DMs who do have long hoses on their secondaries. I'm not uniformed; I have a difference of opinion.

You don't know what you don't know....

It is these type of attitudes that keep killing people in caves.
Since you are so informed, tell us what is the no.1 thing contributing to deaths in caves?

 

[TheRedHead]

Jason, why don't you tell me, from your experience diving Devil's Throat, how this swimthrough is the same or different from caves where people get themsleves killed from entering them without proper training in cave diving which includes 3 sources of light, continuous line to the entrance, diving the rule of 1/3s and not exceeding your MOD.

Lamont correctly assesed the real danger and to avoid that you simply follow Rule No. 1. I'm very careful who I dive with.

 

[MikeFerrara]

I didn't dive Devil's Throat with that operation so I can't comment on gas checking. Since there are many routes through the throat, if the group has enough gas (they descend and surface as a group), they can do alternative routes. They are certainly not checking to see if anyone is OOA. That's ridiculous.



You can't run a guideline to the surface on a drift dive. I personally had 2 flashlights although I went through the throat without mine on as I could see perfectly well with all the illumination from the other lights. It's one way in and one way out. You can't get lost here. The real dangers, from having done the dive, are paranoid narcosis and getting stuck on the top from poor buoyancy control.

To be honest, we don't always run a line to the surface even though that's the way the "rule" is worded. Some of the caves we dive have their entrances way out in a lake, river or ocean. We do ALWAYS run a line to open water such that reaching the end of your line means that you can make a direct ascent. We never assume that we will be able to see. You say that you can't get lost in there but have you tried to navigate it without a mask? Masks come off and visability can be lost in anumber of ways. there may only be one way out but can you find it without the benefit of sight? It's a lovely feeling to feel in all directions and find nothing but rock (or coral). At no time do we want our survival to depend on out ability to see the way out...hence the line... but we like to see...hence the lights.

You can't count on the light from other lights, which is whay all trained cave divers carry three lights and all trained cavern divers carry 2 lights. No exceptions. Three in a cave (beyond the naturally lighted zone) and two in a cavern (the lighted zone) with the third being the sun. It doesn't matter how many divers or lights there are. It doesn't matter how sandy the bottom is. It doesn't matter how simple we think the cave is. When your neutral midwater there are an infinate number of directions to go. It might take a while to find the right one. Time means gas and the more time you waste the greater the chances that you'll run out of gas before you get things sorted out....one possible use for one of the two thirds that you reserved for your exit. Hopefully it will be enough but history teaches us that it isn't always enough which is why a reserve of two thirds is the most liberal gas plan we ever use.

Then of course there are the cases of lost lines, buddies lost off the line and broken lines.

 

[MikeFerrara]

Jason, why don't you tell me, from your experience diving Devil's Throat, how this swimthrough is the same or different from caves where people get themsleves killed from entering them without proper training in cave diving which includes 3 sources of light, continuous line to the entrance, diving the rule of 1/3s and not exceeding your MOD.

Lamont correctly assesed the real danger and to avoid that you simply follow Rule No. 1. I'm very careful who I dive with.

No no no no...he's not talking about the DIR rule number one..."don't dive with strokes". I believe he's referencing the 1st rule of accident analysis. There are LOTS of dead people who have...excuse me..."had" the the same arguements that you have...but I'm only going in a little way...there's only one way out...I can see fine with my one little light...I won't need a line. That's where those rules came from. Lots of the divers who died teaching us these rules died within spitting distance of the exit. some were within touching distance of the exit when they turned the wrong was down a passage that they didn't even know was there.

 

[TheRedHead]

The real cave-like part of it, the throat, is only 3 feet in diameter. You can't turn around. You can go forward or backward.

I mentioned that the number one rule of cave diving was not to enter caves without proper training in cave diving. Devil's Throat is a recreational dive, albeit an advanced one. Don't dive Devil's Throat with unsafe divers would be a good piece of advice. I wouldn't want to deal with someone trying to back out in front of me.

I don't see the point of running a line in a 3 foot diameter hole in a reef. The best thing to do is finger walk and keep you fins out of the sand so you don't foul the viz for the person behind you.

 

[lamont]

Lamont correctly assesed the real danger and to avoid that you simply follow Rule No. 1. I'm very careful who I dive with.

That's just the highest danger that I see.

I'm not cavern/cave/wreck certified, I haven't done the dive, and honestly reading through this thread I don't think I'm able to assess weither or not this dive calls for a continuous guideline, lost line drills and other hard-overhead skills. I'm inclined to err on the side of thinking it should require them and listening to those who do have the training.

I think it clearly should require at least redundancy and training to use it (either doubles, large tank with H or large tank with slung pony) and training in multiple failures and anti-snowballing techniques -- particularly training in promptly moving up the water column and getting out of dodge.

 

[MikeFerrara]

redhatmama
Not to answer for Jason but the similarity is that divers think they can get away with it because it looks so easy. It's also similar in that you think it's ok because every one else does it and you think that makes it reasonable and that you can do it too. For every person that's died because the went into a cave without the right training, equipment or skills there are many who went in the same way and got away with it. Most of the diver who dies may have gotten away with it many times themselves. They just didn't get away with it everytime.

The purpose of the rules and the skills learned for cave diving is to not leave anything to chance. Our intention is to take charge and insure our survival even whern things go wrong. Any sheet for brains can get through it when nothing goes wrong. It's the one dive in a hundred or even a thousand that doesn't go right and that's what we're trainaing for.

All the precautions that some of us are recommending are cheap considering the cost of being wrong. Why don't you explain what makes devils throat such an exception that nothing that's been learned about diving in overhead environments in the last 50 years applies?

 

[hmv-alp]

There are LOTS of dead people who have...excuse me..."had" the the same arguements that you have...but I'm only going in a little way...there's only one way out...I can see fine with my one little light...I won't need a line. That's where those rules came from. Lots of the divers who died teaching us these rules died within spitting distance of the exit. some were within touching distance of the exit when they turned the wrong was down a passage that they didn't even know was there.

I have done Devils Throat a number of times, and this is a reach. We're talking about Cozumel here, not the Andrea Doria. The Throat is a swim through. You can go through without a flashlight; lots of people do. Coz is all DM led drift diving. The operators who will take divers to the Throat will do so only if the divers have the ability for deeper diving. Dropping a line through Punta Sur is against the law. Divers need to know the dive operators are safe, and the operators need to be aware of the divers abilities. Fortunately, there are a number of really great dive operators in Coz. Very small dive groups, large steel tanks, mandatory computers. I've seen any number of shops in Florida who I wouldn't do a dive like this with under any circumstances!

Divers have the responsibilty to evaluate different situations and decide what they feel comfortable with, as do the dive operators. You can't have hard and fast rules that cover all divers in all situations. And there will always be people who make foolish decisions in any endeavor, whether it's diving, driving, or crossing the street. If this were a true overhead environment, then it would be different, but Devil's Throat/Punta Sur is not that challenging a dive. The currents are the biggest potential challenge, not the swim throughs.

 

[ShakaZulu]

http://www.scubaboard.com/showthread.php?t=121605

No more questions your honor...........