Cave and Wreck diving

[MXGratefulDiver]

More to the point: This in NOT an open water dive, unless you stay within about 10" radial feet of the deck/ladder. It IS a very nice "Cavern" dive, where much of the area can be explored within sight of the surface. I think this is where people get mixed up. Under most agencies I am familiar with; your primary light source in a "Cavern" dive should be the Sun/Surface light. If you are unable to see well enough to exit without a dive light, you are really past the "Cavern" zone and into the "Cave" zone.
At the Warning sign in Paradise Springs; you are at ~95' in depth and over 75' away from the surface at roughly a 45* angle. Yes, you can see surface light from there. Depending on water viz, it might look about the size of a small orange. It would not take much for another diver so silt out the cavern and really shut off that light source.

I don't think that's the generally recognized definition of a cavern. It's been many years since I was last in the Ballroom at Ginnie ... but I don't recall it as being someplace I'd want to be without a light. Same goes for Dos Ojos, Gran Cenote, Pet Cemetary or Car Wash in Mexico ... and those are probably the most popular cavern dives available down there.

I think the accepted definition of cavern involves being able to see ambient light at all times, and maintaining a max linear distance of less than 130 feet to the cavern entrance. There are also depth limits ... 60 or 70 feet as I recall.

... Bob (Grateful Diver)

 

[tbone1004]

it all depends on what you want to see and dive, but there are also two very different cultures between cave and wreck diving that appeal to others.

Here's my story. I am primarily a cave diver. Why? It's a helluva lot cheaper than wreck diving, but it's also a lot more relaxing. When I was in college, gas was $4/gallon and I couldn't afford to dive off of the coast of NC because there were long drives out to the wrecks and the charter fee+fuel surcharge was nuts. I would get 2 dives/day, but at a cost of $500/day for a lot of the off shore wrecks, not including food+fills+loding. It was nuts. Conversely, I could go to Cave Country for 3 days, spend about $400 all inclusive, and dive on my own schedule. That is still relevant today, though the charters are less expensive, they're still more expensive than cave diving.

I go to cave country as a "vacation". I check out from the real world, I relax, dive on my own schedule, and enjoy spending time/drinking beer with good friends both new and old. The social aspect of cave diving is brilliant. Tough to get that in wreck diving, and it's also difficult to meet a lot of new divers wreck diving since the boats are largely limited to 6 packs and you find your dive group and that's about it. Right now I have about the same drive to cave country as I do to NC Wrecks, and I will go to cave country every time, despite enjoying the actual diving in the ocean more.

My fellow Maineiac is spouting cave bull at saying cave training trumps wreck training, and to a certain point it's true. Cave training does not prepare you to dive wrecks. HOWEVER cave training offers you the best foundation to get into proper wreck penetration due to zero viz, line skills, etc etc that are often skimped in wreck training. It's certainly not exclusive, but it is definitely the rule. He started wreck diving when you had to do progressive penetration, lights sucks, gear sucked, no one was laying line etc etc. Now very few instructors are teaching wreck penetration the "easy" way using skills and techniques that were developed by cave divers. Just because you are a full cave diver with however many thousands of dives in a cave, 100% does not mean that you shouldn't take wreck penetration training because there are a lot of nuances to wreck penetration and ocean diving in general that you need to know to do it safely. I would be hard pressed to find a wreck penetration instructor that wouldn't prefer all of his students to at least be cave trained at the intro level prior to wreck penetration though. Saves a lot of time and effort with buoyancy, propulsion, and line techniques.

 

[Caveeagle]

I don't think that's the generally recognized definition of a cavern. It's been many years since I was last in the Ballroom at Ginnie ... but I don't recall it as being someplace I'd want to be without a light. Same goes for Dos Ojos, Gran Cenote, Pet Cemetary or Car Wash in Mexico ... and those are probably the most popular cavern dives available down there.

I think the accepted definition of cavern involves being able to see ambient light at all times, and maintaining a max linear distance of less than 130 feet to the cavern entrance. There are also depth limits ... 60 or 70 feet as I recall.

... Bob (Grateful Diver)

Yes, I admit that I have not compared all the agency definitions side-by-side. I will look up a couple of my books, but I know that counting the Sun as your "primary light" is a principle in at least one of the major agencies.

And, Just because Ginnie, Blue Grotto and Paradise allow open water divers there (with Lights) does not suddenly make them a "Open Water" dive. They have been deemed "relatively" safe with permanent lines and little to no risk of getting lost. That plus the motive for profit, have allowed the operational definitions to be blurred.

So, even if your an open water diver with three lights, I still feel being at 95-100' depth in Paradise is a VERY risky situation for an OW diver. Imagine making an emergency ascent from the 'Warning Sign', add to that a possible silty obscured line of sight to the surface (from dragging that octo through the silt on the way down). Line, what line?.. Most OW/AOW divers are not trained in line drills, ,..and will most likely rocket ^UP^...not thinking about the need to go out and up at the same time.

**I know its a bit of a threadjack. But I think this is an important side topic on safe overhead awareness.

 

[MXGratefulDiver]

.. a cavern dive is not an open water dive. Cavern diving is overhead diving, and should be accompanied by the appropriate training. Yes, I know some places allow open water divers in caverns ... that's a topic worthy of discussion, but it does not define cavern as open water.

I interpreted your post as an attempt to define a cavern dive. My definition comes from the National Speleological Society (NSS) ... as does my cave training ...

... Bob (Grateful Diver)

 

[boulderjohn]

More than a few people think the definition of a cavern includes open air between the water and the cave ceiling. That is not true. I don't know of any agency that requires daylight as the primary light source in a cavern.

 

[boulderjohn]

What I am about to describe is admittedly a bit simplistic and dependent upon my location to a large degree, but it aptly describes the major difference between cave diving and wreck diving for me.

With caves, you usually have a cavern zone followed by the true cave area. If you are going into the cave, you need appropriate cave training--period. There is no cave that does not call for it. If I am entering a cave, I am minimally bringing all the required gear and skill taught in cave classes, and I will sometimes need more.

The same would be true of SOME wrecks, but by no means all. I spend a couple of months a year in South Florida, and I do a lot of wreck diving there. Many are at recreational depths, and the penetration possibilities are almost exclusively wide open and well lit. OW divers routinely penetrate with nothing but their OW gear and single tanks. I also dive wrecks at technical depths, but I don't do much (if any) real penetration with them, and I don't see many other people on those boats doing it, either. It's been a long time since I have had any reason to run a reel in a wreck. Most of those wrecks were intentionally sunk as part of an artificial reel program, and in most of the cases, holes were cut before the sinking to make sure there was enough adequate light and open exits to minimize the danger of entrapment.

Sure there are wrecks that demand advanced wreck training, but there aren't that many that are easily accessible to me, and if I want to go to them, there aren't enough others who want to go to them for a boat charter to pay off. It would thus become especially expensive for me to go, since I owuld have to make up for the lack of additonial paying customers. In contrast, I can get to a cave and have the full experience easily, with no extra expense.

For people like me,then, the advantage of cave diving is relatively easy access to caves. I do more wreck diving than cave diving, but it really isn't advanced wreck diving I do, and I don't need any real additional training for it. I haven't done a REAL wreck dive in years.

 

[kensuf]

More than a few people think the definition of a cavern includes open air between the water and the cave ceiling. That is not true. I don't know of any agency that requires daylight as the primary light source in a cavern.

Hi John,

I don't know of any agency that doesn't require daylight. The sun is the primary source of light in a cavern dive.

NSS-CDS

2.1.8 Limits of Training

The participant will be encouraged through this training to develop a clear understanding of the safety limits of the Cavern Diver level of training and will be expected to dive within the scope of these limits both during and upon successful completion of this training:

1. Daylight zone of cavern and within sight of the surface entrance.

TDI

17.2 Qualifications of Graduates

Upon successful completion of this course, graduates may engage in cavern diving activities without direct supervision provided the graduates adhere to the following limits:

1. Daylight zone, i.e. within natural light of the cavern entrance

IANTD

E. Program Limits
....
3. Unobstructed exit / surface light must always be visible.

NAUI

OVERVIEW AND QUALIFICATIONS

This course is to provide the diver with the skills and knowledge needed to gain experience and minimize risks in cavern diving at depths no greater than 100 fsw (30 msw) and at a combined depth and distance penetration no greater than 200 feet (61 m) from the surface and must remain within the daylight zone and no- decompression limits.

And I think the NACD standards mentioned something about Pizza, but let me quote those too.

9. LIMITS:
A. Natural sunlight.

 

[Caveeagle]

And I think the NACD standards mentioned something about Pizza, but let me quote those too.

LOL.....Oh.... this is so tempting to jump in on.

Thanks for the input and detailed references. Thankfully, there have not been many accidents lately in NFL caverns. I still have not seen detailed specifics around the last one in Mexico, but suspect a stricter respect of cavern limits could have saved a life there.

 

[kensuf]

Generally speaking, the limits of a cavern diver as defined by the above agencies include:

1. Daylight zone only
2. 200' linear penetration from the surface (that means 100' deep can go 100' horizontal, 70' deep can go 130' horizontal)
3. No restrictions (a place where you can not swim side by side)
4. 100' maximum depth *
5. No Decompression Limits
6. 40' minimum starting visibility *
7. Rule of 1/3rds in a single tank, rule of 1/6ths in twin cylinder configuration
8. 2400 PSI in an AL 80 to start a dive *
9. Continuous guideline to open water *

The above will cover the majority of agencies I'm familiar with. Minor differences include Depth (TDI 130' max depth, IANTD up to the divers certification level), 40' vis (NACD 30' starting vis), Starting Volume (some mandatory 58 cubic feet, some mandatory 72 cubic feet, etc), and continuous guideline to open water or a "safe exit" (being right at the inside of the overhead).

 

[diver42]

At the Warning sign in Paradise Springs; you are at ~95' in depth and over 75' away from the surface at roughly a 45* angle. Yes, you can see surface light from there. Depending on water viz, it might look about the size of a small orange. It would not take much for another diver so silt out the cavern and really shut off that light source.

That sounds like a cave to me. Especially if there's rain or even sudden clouds.