Info Why are tables not taught in OW classes anymore?

[Akimbo]

@Akimbo: how do you upload something for inclusion in SB Download Library? -- posted instructions are for KnowledgeBase, not for Library).

Basically the same process but with a little less formal reviewing. Create a thread in an accessible and appropriate forum and we can move it into the Library if it is approved. You can even use the Report function on your own thread to nominate it.

If you can, please try to follow the format used in most of the existing OPs in the Library for consistency, but feel free to be more verbose if you feel it will be helpful to members.

 

[Pressurehead]

OK if I was diving with you in QLD I would have to finish a dive with 50 bar. Legal requirement yes?

Most Australian dive operators will insist that you are back on board the boat with at least 50 bar (725 pounds per square inch) in your cylinder.
It is not policed, they write down your bar left and depth on the sheet, you sign it, they really only count heads [as they should].
you are not one of those that go around making a big deal out of " I spent this amount of time and have this amount of gas left' types?
They are wankers.
You are not one of those?
After 45-55min most dives I have had enough [as good as the dive is], does not matter if I have 100 bar left.
It is not a contest.

 

[John C. Ratliff]

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 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,

I think you say I “disparage” your dive when I really did not. What I was trying to communicate was that the planning for diving was much different in the 1970s than it is today, and in that happening I think some things are lost. Some other things are gained. Overall, I applaud computer usage, as I had a hand in the development of machines which write a single layer on a computer chip. But we also must remember what was lost, and whether some of that can be recaptured.

SeaRat

 

[Blackcrusader]

Most Australian dive operators will insist that you are back on board the boat with at least 50 bar (725 pounds per square inch) in your cylinder.
It is not policed, they write down your bar left and depth on the sheet, you sign it, they really only count heads [as they should].
you are not one of those that go to go around making a big deal out of " I spent this amount of time and have this amount of gas left' types?
They are wankers.
You are not one of those?
After 45-55min most dives I have had enough [as good as the dive is], does not matter if I have 100 bar left.
It is not a contest.

Nope not one of those types. Many ops will say max time 60 mins then I stick to that. Some ops are dive as you please as long as you have the air for that. When I was in Lembongan with Tamarin Divers in Bali the owner would dive with us and at 50 mins put those low on air around 60 bar in one group and those with sufficient air do longer dive times. It's always follow the dive ops rules. In Bohol I am a repeat customer but any divers good on air who want more than 60 mins are asked if they want to do longer dives with me. Some say max 75 mins as they feel cold so we do 75 min dives. If a dive buddy wants to call a dive if they are cold we do so.

 

[John C. Ratliff]

You will have to explain why that makes any difference.

Not enough air to get into a decompression situation with a single 72 cubic foot tank, especially if you need to surface with 500 plus psi. I’m not as sure about a single AL80, but the same reasoning goes.

SeaRat

 

[boulderjohn]

Having been involved with countless versions of this thread over the nearly 19 years I have been involved with ScubaBoard, I have seen pretty much all the arguments. I would like to summarize one from probably about a dozen years ago. The topic is the mantra "plan your dive and dive your plan."

One of the participants, a well-known diver named John Chatterton, argued that one of the best advantages of omputer use was that you did not have to plan your dive and dive your plan. To do that, you need to know what you are going to encounter throughout the dive. His favorite diving activity was exploring wrecks, and on such dives, he could never be sure what his maximum depth would be or how long he would spend at any depths. By monitoring the computer, he could make real time decisions. With him and his buddy both carrying two, they did not have to worry about computer failures.

He convinced no one that I could see. He finally signed off the discussion by saying something along the lines of "You guys must do very boring dives."

 

[tursiops]

Not enough air to get into a decompression situation with a single 72 cubic foot tank, especially if you need to surface with 500 plus psi. I’m not as sure about a single AL80, but the same reasoning goes.

SeaRat

That myth about not being able to go into deco with 72 cuft was born when NDLs were longer and SACs were higher. Work it out using today's common SACs and todays NDLs. You can very easily go into deco with a 72, so of course also with an 80.

 

[boulderjohn]

That myth about not being able to go into deco with 72 cuft was born when NDLs were longer and SACs were higher. Work it out using today's common SACs and todays NDLs. You can very easily go into deco with a 72, so of course also with an 80.

Go to the Cozumel forum and you will find plenty of threads in which people talk about doing 60-80 minute dives using AL 80s. These are all multi-level, NDL dives using computers, but they would all be far past table limits.

 

[tursiops]

Go to the Cozumel forum and you will find plenty of threads in which people talk about doing 60-80 minute dives using AL 80s. These are all multi-level, NDL dives using computers, but they would all be far past table limits.

That's not the point. The false statement is that a 72 cuft tank doesn't have enough air to allow you to go into deco.

 

[Eric Sedletzky]

That's not the point. The false statement is that a 72 cuft tank doesn't have enough air to allow you to go into deco.

If somebody is dumb enough to be doing dives deep enough and long enough to go into deco on a single 72 then they need to re-think their diving habits.