What defines a "cave"?

[Cave Diver]

People don't die doing Hawaii lava tube scuba tours, and some people may be surprised. There is a briefing; silting is discussed, but Hawaii sand is not usually silty. Gas management is unchanged for the most part; It is rare to spend more than a third of the dive in the overhead environs, there is more life to be found out on the reef. Get in, get it over with, get out on the reef.

I won't argue with you about the safety or not about diving lava tubes. I haven't done those, I'm not familiar with them beyond the discussion we had about it during my cave training and I really have no desire to do them. I have no clue if they're 5' or 50. If they're silty or rocky. If there is flow in them or not.

But in light of the fact that most OW classes don't teach any sort of gas management beyond "be back on the boat with 500 psi" I think it's irresponsible to take brand new divers into this type of environment.

All you're teaching them is that it's ok to enter this type of environment with no training. Sure, they might be ok on the dive they did with you, but what happens when they think it's ok and decide to do it on their own? Or when they go to Mexico and think it's ok to go into a cenote without training? Or Florida and do a spring?

 

[Cave Diver]

The guest does not need a light on these dives, but they will see more if they do bring one; most operators don't rent lights for day dives. There are some divers who chose not to go in; just follow the bubbles to the other side.

Can you elaborate on this statement a bit more? Why aren't lights needed? Are the tubes that short? Do they have skylights, or how are they following the bubbles?

 

[sea_ledford]

I'll elaborate, since I've guided many a diver through those caverns...

Most divers do not have lights, yes there is ALWAYS ambient light, most of them have sky lights as well, some are indeed very short (10-20 foot swim troughs, but still "overhead"). And if someone saw the opening and decided not to go through, we would come back out the same way and pick them up, if we couldn't point to the exit and tell them to meet me there in two minutes. At First Cathedral even if someone was waiting at the entrance, they could still be seen from the back of the cavern.

I've actually freedove both the main Catherdrals with out pushing any personal limits.


There was one that we rarely did that was by all definitions a cave. It was long (150 feet maybe?), narrow (but you could squeeze 2 divers side by side), and it got pretty dark without a light. I don't remember the depth, 40 feet maybe? but it was definitely further than 130 linear feet from the surface! The only thing it didn't have was forks, so at least you couldn't get lost. I don't think I ever took unknown divers through there, but after a dive or two with someone we would consider it. We rarely went because it was rare that we had the right group of divers. Probably stupid in hindsight, but I'm sure people still go there.

I'm on the fence about where to be on the overhead environment thing, but I think Florida based divers tend to go a little overboard on it (for a very good reason for their environment). I learned to dive in Northern California, and I consider diving under a thick kelp paddy a hell of a lot more dangerous than diving through the Cathedrals or other swim through/ caverns in Hawaii. But a kelp paddy isn't considered overhead is it? Or should all California divers have to take cavern training as part of their openwater class?

Chris

 

[Dive-aholic]

There is specialized kelp diving training available in California. Kelp beds have their own hazards that need to be considered that aren't covered in a cavern course so a cavern course wouldn't do much to prepare a diver to dive the kelp beds.

 

[Paladin]

And at least 1 OW diver has died there. Others have panicked there.

The only OW diver death at Ginnie Springs (Ballroom) that I could find a record of was not caused by the overhead environment. The diver was having trouble equalizing and was taken back to the entrance by another diver. She was later found unconscious and unresponsive by another diver outside the entrance.

 

[Cave Diver]

Most divers do not have lights, yes there is ALWAYS ambient light, most of them have sky lights as well, some are indeed very short (10-20 foot swim troughs, but still "overhead"). And if someone saw the opening and decided not to go through, we would come back out the same way and pick them up, if we couldn't point to the exit and tell them to meet me there in two minutes. At First Cathedral even if someone was waiting at the entrance, they could still be seen from the back of the cavern.

My concern isn't so much as a diver being in a 20' swim through with no overhead training, as much as it is about setting a precedent.

If a 20' swim through is ok, is a 40'? 100'? At what point do you tell a newer diver that one is ok and another is not? Because it has doesn't have silt? Or because it doesn't have skylights? Are the divers being educated enough to make these distinctions on their own, or do they just think "oh it's no big deal, I've already done this?"

I'm speaking from a been, there, done that perspective. My OW class didn't talk about the dangers of overhead environments. We don't have any around here. We talked about stuff like the dangers of going deep without training and diving oil rigs, because that's what our local diving consists of. My first trip to Mexico, a DM led us through a couple of long coral swim throughs. Towards the end of the trip I was hanging out with some of the more experienced divers and they invited me on a dive that had a cave. One of the divers dropped their only light at the entrance, where I found it later. At one point we were out of sight of the entrance, out of the daylight zone with no ambient light and in a complete overhead. There were three directions we could have branched out from that point. One took us back the way we came. The other also went back towards the entrance and the third took us deeper in the cave.

For the most part I thought it was ok, because we'd already been in tunnels earlier in the trip and I was with other more experienced (to me) divers. Luckily I was still new enough to be a little scared to press too far into the cave and as soon as I realized I was out of sight of the entrance I turned around. At the time I had no comprehension of how much more dangerous that dive was than a swim through - it seemed like pretty much the same thing to my newbie mind.

In retrospect half the stuff I did before I knew better would scare the crap out of me now.

 

[sea_ledford]

My concern isn't so much as a diver being in a 20' swim through with no overhead training, as much as it is about setting a precedent.

If a 20' swim through is ok, is a 40'? 100'? At what point do you tell a newer diver that one is ok and another is not? Because it has doesn't have silt? Or because it doesn't have skylights? Are the divers being educated enough to make these distinctions on their own, or do they just think "oh it's no big deal, I've already done this?"

Well that's the rub, isn't it? I'm sure if you ask any diver, most of them will say that at least some point in their diving career they have been somewhere or done something that was beyond their training and skill, and that hopefully prompted them to get additional training.

I think those dives are very helpful in the grand scheme of things. I was actually back in a cavern that turned into a cave on the north shore of Maui and at one point realized I had NO business being back there, and promptly turned around. If I don't have those humbling moments on occasion, I think I would lose some respect for the ocean (or the cave, or the gear, or whatever) and then go do something really stupid.

All we can do as instructors is give them the most relevant information we can and hope that life experience in combination with diving experience will keep them alive. I try to emphasize what we can live without in my classes. How long can you go without food? How about water? How about air? Yeah, you're underwater! Everything you do, including just being down there is a big deal!!

Chris

 

[Cave Diver]

All we can do as instructors is give them the most relevant information we can and hope that life experience in combination with diving experience will keep them alive.

Does that include leading them into such situations? If so, are you a certified instructor for those types of dives?

 

[kanonfodr]

Here is the flaw I find with this reasoning. OW divers don't know what they don't know. They don't know the difference between a benign cave and dangerous one. They have a dive leader taking them through swim throughs and tunnels in Mexico or wherever and every thing is ok, and so that's the impression they have of all caves. Then they find themselves in Florida or somewhere and decide to take a peek into one of those caves.

What can it hurt? They've already been in one. It's no big deal, right?

I'm not going to argue reasoning, as that is an individual responsibility. But I see a difference between these lava tubes:

IDH 21 Nov 2010 on Vimeo Sea Cave
Maybe 100 feet long, depth from 45-30 feet at the bottom, VERY spacious. Combination rock/ heavy sand bottom that doesn't lend itself to silting.

Makaha 11 Nov 2010 on Vimeo Makaha
Mostly reef dive with interspersed lave tubes and swim-throughs ranging in length from 2 feet to maybe 40, depths 30-40 feet, generally 6+ feet across. Once again, bottom composition doesn't lend itself silting.

Shark's Cove 5 December 2010 on Vimeo Shark's Cove
Multiple overhangs/tubes/caverns, depths 15-40 feet depending on tube, all shapes, lengths, and sizes. Bottom composition doesn't lend itself to silting, but haloclines are frequently observed depending on the tube.


and this type of cave:
Cave diving in the Devil's System at Ginnie Springs, Florida on Vimeo Ginnie Springs

First of all I appreciate the varied positions on this subject, and empathize with everyone who is saying that these dives shouldn't be done. But considering the amazingly different conditions between the Florida caves and the Hawaiian lava tubes, most people would consider these tubes far more benign (although certainly not without danger) than the Florida or Mexico fresh-water caves. They are simply different beasts, just as different as a Pit Bull is different from a Shih Tzu. Both can kill you, but IMO in order to die from Shih Tzu you've got to be A) asking for it and B) incredibly stupid.

I will agree that Hawaii divers are far from the most exceptional in terms of diving skill and knowledge (this is Perma-Vacation Diving, here!!) in general (even though we do have highly skilled and knowledgeable divers around) for various reasons which are media for a different thread. But judging once again from the lack of bodies being fished out of these tubes, throughout history, I would judge these tubes here to be fairly non-threatening. On the back of that coin, I wouldn't go near the Florida caves without training.

My concern isn't so much as a diver being in a 20' swim through with no overhead training, as much as it is about setting a precedent.

If a 20' swim through is ok, is a 40'? 100'? At what point do you tell a newer diver that one is ok and another is not? Because it has doesn't have silt? Or because it doesn't have skylights? Are the divers being educated enough to make these distinctions on their own, or do they just think "oh it's no big deal, I've already done this?"

...

In retrospect half the stuff I did before I knew better would scare the crap out of me now.

And precedents are different wherever you go. A woman walking around in Taliban-ruled Afghanistan in a bikini would likely be jailed, but could get her head chopped off. In Hawaii, that's the dress code. It sucks, and inevitably there will come a day when some idiot will die in a lava tube.

It's unfortunate, but there are no instructors that I'm aware of with teaching credentials for overhead environments so folks do as they please. I'm going to take advantage of my station here in the mainland to get GET cave training, so I can go back to Oahu later on and explore the tubes in a manner conforming to the desires of many posters here on this thread, as well as my own.

And I would be surprised if more than half of all certified divers HAVEN'T done something outside of their training. If they die, then those who know better call them idiots. If they live and tell about it on Scubaboard, then they are called Idiots Who Survived. In some cases I wholeheartedly agree with that label being applied to posters on this board, but what I call idiotic may be perfectly fine to someone else. In some cases, stupid has to do for whatever reason.

Peace,
Greg

 

[MauiScubaSteve]

Maybe if they were better educated about the hazards and things that can go wrong on dives beyond their training as brand new OW students, they wouldn't be in such a rush to do these dives "soon?"

Since nearly every dive boat in Hawaii "only" offers guided diving, and since nearly every guide working those boats is an instructor, perhaps the more new divers "we" take beyond their training the better.

How many brand new OW divers are having things go wrong in caves? How many of those brand new OW divers who had things go wrong in a cave went into that cave because of the "bad example" set by tropical lava tube/cavern tours?

Oahu has some killer caves, at one of the most popular shore dive sites in the entire State of Hawaii. Years ago four "NAVY divers" got lost and ran out of gas; ironically right under the gas station across the highway. That cave is now referred to as the Gas Chamber. Decades of dumb a$$ divers later and there have been no other deaths; even the many non guided new OW divers are surviving lava tube/cavern dives.

*military for sure, many different bases on Oahu back then, one version is NAVY Divers; confirmed as active duty, certified divers.