Cavern with single tank?

[Esprise Me]

A friend and I have been talking about taking a cavern course together. The stars are expected to align probably no sooner than a year and a half from now, so obviously a lot of things will change. But currently, she has a little over 50 dives and I have a little over 100; she is excellent on air consumption and I'm fine; she is very interested in caverns but has no interest in caves or any type of technical diving, while I could see myself at least dipping a toe in the waters beyond rec limits someday. I've taken GUE Fundamentals Part I; I'm working on getting into a drysuit now and thinking of doing a doubles primer before I go back for Part II. We agree we want to do the course in Mexico rather than Florida. I was looking at Natalie Gibb as an instructor, but I notice she requires a TDI intro to tech course or equivalent as a prerequisite, which seems to be her standard, not TDI's. Reading between the lines, it seems like she mainly wants you comfortable with doubles or sidemount so you can use that during the course. I might end up taking an equivalent course by then anyway, but it might mean an extra expense for my friend, who seems pretty clear on her rec limits.

So my questions: does it make more sense to take cavern in a single-tank configuration if you know that's as far as you want to go (i.e. never cave/tech)? Does it make sense to do cavern in a single tank if you think you might possibly go beyond cavern someday? Does it make sense for two people, one who is definitely not going beyond cavern and one who might, eventually, to take the class together?

Full disclosure: I don't always like people. I like this person and am inclined to try to make dive trips work with her, even if that may conflict with making the maximum amount of progress as a diver.

 

[grantctobin]

I like Ken Sallot’s / @kensuf thoughts on the matter. Training – Dive Gainesville

 

[Lorenzoid]

I think Ken's is the growing school of thought on Cavern. A cavern is a cave, or can turn into a cave quickly and unexpectedly. If you want to dive anything cave-like in earnest, get cave certified, and that means dual cylinders. If you just want to satisfy curiosity about those holes in the ground, learn why they can be dangerous, and decide whether the environment is interesting enough to you to entice you to take cave training, then by all means take a Cavern course--in single-tank configuration.

I was looking at Natalie Gibb as an instructor, but I notice she requires a TDI intro to tech course or equivalent as a prerequisite, which seems to be her standard, not TDI's. Reading between the lines, it seems like she mainly wants you comfortable with doubles or sidemount so you can use that during the course.

I would recommend completing Fundies and then getting comfortable with doubles or sidemount. That should satisfy Natalie's prerequisite. As for your friend, well, I guess she needs to make a decision.

 

[Superlyte27]

I've only had one student ever take cavern and not get hooked and become a cave diver.

 

[Norwegian Cave Diver]

In the Playa Del Carmen/Tulum area there is Dos Ojos. It is the place most often divers go - with a guide only - to experience an overhead environment - in this case - loosely called a cavern dive. Yes you will in an overhead environment and see daylight for a huge majority of the dive to either the “Barbie Line” or the “Bat Cave” areas. That where it all began for me. Your either going to love it or decide an overhead environment isn’t for you. IMO you should consider beginning with that. If you want to get certified then ...The dive shops will likely expect you to be AOW or more with 100 + dives and be very comfortable in the water. In all of the certs that I have - Cavern was the best. Most demanding. Highest expectations. As it should be considering it is the prerequisite to Intro to Cave. You can likely do Cavern on single tank - but I’m not sure why you would want to do that? The idea is to be backmount doubles or better yet side mount. You really want to have a second completely redundant system while in an overhead environment. Pm me if you want.

 

[Lorenzoid]

Well yeah, if you haven't even done one of those guided cenote cavern dives, then definitely start with that. It's what got me and many others hooked! Dos Ojos is a great one.

 

[wetb4igetinthewater]

So my questions: does it make more sense to take cavern in a single-tank configuration if you know that's as far as you want to go (i.e. never cave/tech)? Does it make sense to do cavern in a single tank if you think you might possibly go beyond cavern someday? Does it make sense for two people, one who is definitely not going beyond cavern and one who might, eventually, to take the class together?

I'm of the opinion that my configuration should be appropriate for the environment in terms of being sufficient for the worst case scenario. Typically this is catastrophic gas loss, including a first stage failing shut (My Own Out of GAS Experience). If I am able to donate/receive gas to/from my buddy, at any time, then sure, single tank works. But if at any time I may be on my own and have to take care of myself, then a sufficiently sized redundant gas source is in order.

 

[Esprise Me]

Sorry, I should have mentioned I've done two cavern dives already at Dos Ojos, so I have a good idea of how much I'll enjoy it, at least. I was a very new diver, and in retrospect was probably pushing it being there, though I did manage to avoid bumping into anything or anyone. I only had to put my index finger down once, to stop my forward momentum when the person in front of me stopped. I'm going to Cozumel in June and hoping to squeeze in another day of cenotes; my goal is to nail the back kick before then. But there won't be time for a cavern course on that trip.

 

[BabyDuck]

I did cavern and intro in a single with an H valve, knowing I planned to go through full and would move to doubles later. Turned out, it wasn’t much later - it was about a month after intro I started diving doubles. But I’m glad I went slow.

 

[tbone1004]

@Esprise Me have you talked to Nat about doing cavern as a recreational course? I think @kensuf hit the nail on the head with his philosophy on cavern, though it is certainly not a "new" school of thought. Almost as old as Ken himself

I think that if she is adamant that she will never want to cave dive, then just take cavern in a single tank and call it a day. Nat is a huge cave explorer and sidemount diver though, and may not be willing to teach recreational focused cavern in backmount. She may though so I would definitely ask.