Info Why are tables not taught in OW classes anymore?

[Bigbella]

Teaching students bubble mechanics and circulatory physiology are going to help them in what way?

To ably open a can of 7-Up without it foaming all over the deck . . .

 

[John C. Ratliff]

Oh, come on John, I wear them both all the time. I lived in Portland for 8 years, but never dived in the Clackamas River. I did catch some great salmon and steelhead while I lived there.

Somehow, that never occurred to me! I am a minimalist diver, I don’t like wearing anything that I’m not using at the time (although sometimes I do—octopus regulator, for instance). I like being as streamlined as possible, as I dive high current areas.

SeaRat

 

[John C. Ratliff]

Let's just say, for the sake of argument, that they're called diving for the day, after their Teric has crapped out; and that they'll snorkel, for the benefit of the sharks, and pick up diving the following morning, with the use of tables.

Neither dive tables or the fanciest of Canuck computers are any measure of physiology, eh; they're best guess models, dependent upon any number of factors, not including the fitness or even more commonly, the unfitness of the diver, whether you've spent two hundred or twelve hundred dollars.

We all must have been stupid-lucky back then -- and all in great shape.

My first fifteen years of diving were before the advent of computers; and those whom I knew who eventually contracted DCS, exclusively did so, much later, pushing limits on computers, not tables . . .

That was my point, early in this discussion. The one thing that the tables do is force the diver to actually plan their dive, then “dive the plan.” Now, no one seems to really plan their dive. Today’s divers rely upon the dive computer, an algorithm, tell them what they have already done, without any understanding by the diver of the underlying physiology of their recent dive.

SeaRat

 

[boulderjohn]

Not if you are diving a single steel 72 or even an AL80. I think that the assumption is with a high pressure, high capacity cylinder or twins (either back-mounted or slung).

SeaRat

You will have to explain why that makes any difference.

 

[Joneill]

Somehow, that never occurred to me! I am a minimalist diver, I don’t like wearing anything that I’m not using at the time (although sometimes I do—octopus regulator, for instance). I like being as streamlined as possible, as I dive high current areas.

SeaRat

Of course - that second wrist computer will get you swept away in high current areas…

 

[boulderjohn]

Let's just say, for the sake of argument, that they're called diving for the day, after their Teric has crapped out; and that they'll snorkel, for the benefit of the sharks, and pick up diving the following morning, with the use of tables.

Neither dive tables or the fanciest of Canuck computers are any measure of physiology, eh; they're best guess models, dependent upon any number of factors, not including the fitness or even more commonly, the unfitness of the diver, whether you've spent two hundred or twelve hundred dollars.

We all must have been stupid-lucky back then -- and all in great shape.

My first fifteen years of diving were before the advent of computers; and those whom I knew who eventually contracted DCS, exclusively did so, much later, pushing limits on computers, not tables . . .

I honestly didn't understand this answer. I think you said, "sure, you can't do a second dive with tables if your computer craps out after the first, but, hey, it's all just guesswork anyway." Is that a fair summary?

 

[boulderjohn]

That was my point, early in this discussion. The one thing that the tables do is force the diver to actually plan their dive, then “dive the plan.” Now, no one seems to really plan their dive. Today’s divers rely upon the dive computer, an algorithm, tell them what they have already done, without any understanding by the diver of the underlying physiology of their recent dive.

SeaRat

You seem to believe that being required to plan your dive and dive your plan is a big advantage, and you disparage those who don't do it the way you were taught back when you were limited to tables.

Years ago I was diving on the big island of Hawai'i, and we set out with a dive plan. I don't remember what it was. As we were heading toward the planned destination, we saw a huge manta ray below us, and we went down to about 100 feet where it was being serviced in a cleaning station. We watched with fascination for a while, and when the manta left, we were about to do the same when an eagle ray came along to take his place. After a while we saw that our NDLs were getting a little close, so we headed up the reef. We stopped along the way at about 60 feet when we saw a helmet conch near a decorator urchin. We watched as the conch got closer and then literally jumped over the urchin, preparing for its next meal. We again checked our computers, moved up the reef, and decided to finish the dive exploring the coral nearer to the surface.

You may disparage me for not doing the planned dive and for getting about 2-3 times more bottom time than I would have had if I had planned the dive using tables, but it was one of the best NDL dives I ever had, and I make no apology for it.

 

[boulderjohn]

Okay, now I’m curious; how if your computer dies on the first dive of the day, do you program that first dive into the backup computer?

SeaRat

This has been mentioned by others already, but I have one computer on my right wrist and one computer on the left wrist. The one on the peft wrist has a built in compass, and the one on the right wrist does not, so if the left wrist computer crapped out and I needed a compass for the second dive, I would have to go to a backup compass.

 

[Bigbella]

I honestly didn't understand this answer. I think you said, "sure, you can't do a second dive with tables if your computer craps out after the first, but, hey, it's all just guesswork anyway." Is that a fair summary?

No.

 

[scubadada]

This has been mentioned by others already, but I have one computer on my right wrist and one computer on the left wrist. The one on the peft wrist has a built in compass, and the one on the right wrist does not, so if the left wrist computer crapped out and I needed a compass for the second dive, I would have to go to a backup compass.

I have a 13 year old AI computer on my left wrist, with no compass, along with an analog compass. I have a modern AI computer on my right wrist that has a compass and a floating north pointer. I also have a SPG. I'm covered. Despite some equipment problems over the years, I have never missed a dive, part of a dive, or any part of a series of dives