"Riding your Computer Up" vs. "Lite Deco"

[boulderjohn]

Going into deco accidentally should give you "lite deco." If you are doing it intentionally for a couple of minutes, you will PROBABLY be OK--as long as nothing goes wrong.

If you are going into deco intentionally, then you are tech diving intentionally. If you are doing so without training, then you are missing some things. Much of what happens in tech training is not just teaching you how to plan that deco (including making sure you have enough gas), it is preparing you for the ultimate difference between planned deco diving and recreational diving--in technical diving, you cannot just go to the surface whenever you feel the need. That means you have to be able to handle all emergencies at depth because you can't blow the stop. If you do blow the stop accidentally, you have to know what to do about it.

Just as one example, if you have a sudden regulator failure, including a free flow, on a recreational dive, you head for the surface. You cannot do that on a tech dive, so you will need to be able to shut that valve down and go to your second regulator. If you don't have one, well, what are you going to do?

 

[KenGordon]

Just as one example, if you have a sudden regulator failure, including a free flow, on a recreational dive, you head for the surface. You cannot do that on a tech dive, so you will need to be able to shut that valve down and go to your second regulator. If you don't have one, well, what are you going to do?

Get gas from your buddy. You planned the dive and the buddy has gas for two.

 

[uncfnp]

Get gas from your buddy. You planned the dive and the buddy has gas for two.

Except that some of us are also solo divers.

 

[boulderjohn]

Get gas from your buddy. You planned the dive and the buddy has gas for two.

For those of you who are wondering about what you learn in a tech diving class, this is one of them: Don't do that!

 

[scubadada]

Going into deco accidentally should give you "lite deco." If you are doing it intentionally for a couple of minutes, you will PROBABLY be OK--as long as nothing goes wrong.

If you are going into deco intentionally, then you are tech diving intentionally. If you are doing so without training, then you are missing some things. Much of what happens in tech training is not just teaching you how to plan that deco (including making sure you have enough gas), it is preparing you for the ultimate difference between planned deco diving and recreational diving--in technical diving, you cannot just go to the surface whenever you feel the need. That means you have to be able to handle all emergencies at depth because you can't blow the stop. If you do blow the stop accidentally, you have to know what to do about it.

Just as one example, if you have a sudden regulator failure, including a free flow, on a recreational dive, you head for the surface. You cannot do that on a tech dive, so you will need to be able to shut that valve down and go to your second regulator. If you don't have one, well, what are you going to do?

Seems like we have been through this many, many times now. Going into deco accidently is a mistake, one you may or may not be prepared to handle. Going into a short deco obligation on purpose, with appropriate planning and gas is a choice you are responsible for. Just when I was going to give @boulderjohn credit for being reasonably flexible in the rec/tech discussion, I am disappointed.

 

[stuartv]

But, what I want to know, what exactly is taught in these classes ( beside skills part) that can't be self taught from resources, both on and offline?

Having taken AN/DP and then Helitrox in the last year and half, I can say that, for the theory part, I had already read Steve Lewis' books (The Six Skills and Staying Alive), Mark Powell's book (Deco for Divers), and a lot of stuff here on SB plus from websites like Andy's (DevonDiver), Mark Ellyat's (inspired-training.com), and others. I did not feel like there was any new information presented to me in the AN/DP or Helitrox classes. Looking back, I think the biggest benefit to the classroom part of those courses was being required to actually go through the formal dive planning process where someone else reviewed it. Knowing how to do something - understanding everything about it - and actually doing it are two different things sometimes.

My feeling is that there is a very loud contingent of people in the scuba industry who have a vested interest in people taking formal training. They actively, loudly denounce any suggestion that anyone can every learn ANYTHING on their own. They have even convinced a number of other people, who don't have a vested interest in training, that this is the case, via the use of FUD. "You don't know what you don't know! And if you do that in scuba, you will DIE!" I think some (both instructors and people who aren't instructors but have drank the Kool-Aid) also have an element of machismo in their self-image that they don't want to lose. "What I do could get you killed and you can't learn it from no dang book!" And maybe even "if I deem you to be worthy, THEN I might agree to teach you how to do it." It's like they are personally insulted if someone else learns to do the same thing from reading a book or online or otherwise simply figures it out on their own. And ESPECIALLY if someone is doing what they do with significantly less dives logged than however many they had when they learned it. "I had 200 dives logged before I took AN/DP and I think that should be the minimum for anyone to take the class."

Of course, this is not everyone. I don't think all who are vested in "the training business" are like this. And obviously not all divers are like that. But, there sure are a bunch of them. And I am DEFINITELY NOT saying that everyone should learn on their own by reading. Some people NEED to have an active instructor. For some subjects, some people don't.

In addition, there are people who are genuinely interested in helping other people learn and advance, but they are hamstrung by the legal and insurance industries. They can't even write a book telling you how to do things without disclaimers that you shouldn't use the book to learn how to do whatever the book is about, for fear that someone will indeed use the book to learn something, then end up suing the author. It often feels like, and this is especially true on ScubaBoard, that some people actively work to ensure that scuba is only ever learned by word of mouth training past on from paid instructor to student. Written materials are done just well enough to be used as support materials by an instructor, but are not well-written enough to allow someone to learn the subject from the written material alone.

It's pretty amazing to me, really. Think about it. You can learn to fly with the classroom work done online at home and be flying solo with less instructor hours than some people want to make you have in order to scuba dive.

 

[scubadada]

Except that some of us are also solo divers.

Me too

 

[KenGordon]

For those of you who are wondering about what you learn in a tech diving class, this is one of them: Don't do that!

Please explain.

If I am at 30m or 40m and out of gas what difference does it make if I have a ceiling?

 

[halocline]

Going into deco accidentally should give you "lite deco." If you are doing it intentionally for a couple of minutes, you will PROBABLY be OK--as long as nothing goes wrong.

If you are going into deco intentionally, then you are tech diving intentionally. If you are doing so without training, then you are missing some things. Much of what happens in tech training is not just teaching you how to plan that deco (including making sure you have enough gas), it is preparing you for the ultimate difference between planned deco diving and recreational diving--in technical diving, you cannot just go to the surface whenever you feel the need. That means you have to be able to handle all emergencies at depth

Just as one example, if you have a sudden regulator failure, including a free flow, on a recreational dive, you head for the surface. You cannot do that on a tech dive, so you will need to be able to shut that valve down and go to your second regulator. If you don't have one, well, what are you going to do?

I agree, immediate access to the surface is a defining characteristic of OW diving. In the example in your last paragraph, the answer is another one of the defining characteristics; you get air from your buddy. You don't have individual redundancy, but the buddy system supplies the redundant air.

 

[stuartv]

Please explain.

If I am at 30m or 40m and out of gas what difference does it make if I have a ceiling?

If you're going to have a ceiling, then you should (per tech training) have a redundant gas supply that is more "reliable" than your buddy. With an NDL dive, if you go OOA and your buddy has disappeared around a corner just at that moment, you CAN go straight to the surface. That is not an acceptable answer (going straight to the surface) when you have a deco obligation and you need to be able to, well, live and not get bent if you go OOA and your buddy has disappeared around a corner.