Teaching Computers in OW class vs tables

[MikeFerrara]

The tables aren't linear, so you can't average the depth.


Terry

Actually you can.

I made the same arguement until I checked it out with verious decompression softwares. If you run some dives planning both as multilevel and using average depth (time weighted you'll see that, within a very close margine, the same tables are generated.

Don't believe me. Try it yourself.

 

[Tampabay]

I agree with RIDIVER501. You should depend on the your Dive table and use your computer to compare. Since computer can fail... You don't want to get lazy and careless. Enjoy your Dives

 

[GDI]

First of all stats have shown that divers who solely dive by computers have had a higher occurrence of DCI than table divers. Divers need to learn to use tables in conjunction with computers. Computers can fail yes, BUT then so can divers in not remembering or learning to use tables. Tables once produced are the collective of data that when used correctly can cover a broad ban of the population of divers. Computers have the ability to provide immediate diver info output. This is handy by all means. However computers do not factor in the way that a particular diver feels from one day to the next. They do not care if you have a cold, they do not care if you are a smoker or if you are fat or thin. They mearly run a algorithum computing data and giving a output. Tables do no better at this either but they are based on a population sample and not particular to the individual diver. (I would suggest that a computer is also population based in it's algorithum programing) Tables may be more conservative in their application. Without preplanning or table knowledge, tables donot provide a diver a great bailout procedure. I have made many dives where I have used the tables I generated in conjunction with my computers. At times the computers have cleared the deco requirements (advantage of real time dive input and output) When this happens I confirm my requirments against the tables and wait until they clear me out of the water. The same has also occurred where the tables have cleared and the computer has not, at that time I hold waiting, to clear the computer. They both, tables and computers need to be taught with each other in mind. When comparing a tables NDL to that of a computer once at depth there really is very little difference in allowable bottom time. The other thing divers need at the base level is to learn how to calculate their air/gas breathing time aka SAC rate. Depth, Environment, Air, Time, Health are the controlling factors to any dive. IMHO

 

[kalvyn]

No further questions, your honor............... Do you realise, people may actually take what you say seriously, apply it and get into serious trouble???

I would strongly recommend the following Course.

http://www.padi.com/english/common/courses/rec/continue/multileveldiver.asp

Yes, I'm aware that people may take what I say seriously, apply it and get into trouble. Every time I tell someone they should learn how to SCUBA I take that chance. What I'm saying won't get people into trouble when done correctly. If people chose to do something without understanding what's really going on behind the scenes (like, say, riding their computer's NDL for the entire dive), they're putting themselves in danger. No one else is at fault. That's known as diving beyond your training, and it's a good way to tempt fate.

Check out this thread for some interesting discussion on computerless multi-level diving:

http://www.scubaboard.com/showthread.php?t=26859

One last question directed at the prosecution: if I was crazy stupid for making that dive in Pureto Vallarta, as well as the second dive that day for a 69 minute bottom time, as I planned them, then why did my Mosquito not squawk about the dives that day? I will post the profiles from those dives that I downloaded from my Mosquito when I get home this evening. Doesn't it follow that if I planned those two dives the way I planned is crazy stupid, then diving a computer is crazy stupid? I mean, the Mosquito let me make those dives without violation so it must be wrong too, right?

You do know that the Suuntos are nororiously conservative, right?

Jimmie

 

[MXGratefulDiver]

Don't dive like I do, one may die as a result.

Jimmie

That's not very a very comforting statement, considering the dives we'll be doing together on Sunday ... :11:



... Bob (Grateful Diver)

 

[ShakaZulu]

Yes, I'm aware that people may take what I say seriously, apply it and get into trouble. Every time I tell someone they should learn how to SCUBA I take that chance. What I'm saying won't get people into trouble when done c
....
crazy stupid? I mean, the Mosquito let me make those dives without violation so it must be wrong too, right?

You do know that the Suuntos are nororiously conservative, right?

Jimmie

That thread is useless. Explain to me, without knowing your dive terrain, not using a computer how you calculate your average depth (if we assume you use that on your tables), and then plan your dive within NDL limits, all while underwater. This is what I don't understand....actually, lets take this convo offline, no need to hi-jack this thread.

 

[kalvyn]

That thread is useless. Explain to me, without knowing your dive terrain, not using a computer how you calculate your average depth (if we assume you use that on your tables), and then plan your dive within NDL limits, all while underwater. This is what I don't understand....actually, lets take this convo offline, no need to hi-jack this thread.

PM sent!

Jimmie

 

[getwet2]

However computers do not factor in the way that a particular diver feels from one day to the next. They do not care if you have a cold, they do not care if you are a smoker or if you are fat or thin.

This is not totally true, with some computers if you know what you are doing you can adjust the conservatism from day to day or from dive to dive if you want. So say yesterday you were feeling great, drop the conservatism down. Today you feel a little tired, increase the conservatism a little bit.

 

[MikeFerrara]

You can't really blame the computer for that. You set it for "ultra-conservative", that's what it gave you.

Well, actually I took the computer out of the bag and straped it on. If I did something to change the mode (of which there is no display telling you that) then I was somehow able to do it by?...I have no clue. You have to go through a couple of nested menues by touching electrical contacts to do it on purpose.

You need to violate a whopping great rule to make it do that.

The Smart-Com will lock out if you blow through all the manditory stops (not just the optional stops you get if you set it to "conservative").

It's a reasonable response, since the condition of your body would then be outside the parameters that the algorithm in the the computer can handle. Your body is in a condition where the computer can't safe dive conditions, so it locks out.[/QUOTE]

Some computers will lock you our for going too deep. Some for too long. You might think it's reasonable but I don't need it.

Can you imagine the lawyer feeding-frenzy that would happen if a diver blew past all his stops, got to the surface, felt OK, then went on another dive "because the computer said it was OK", then got bent?

ok so it's better they just stop telling you anything?

You don't have to like computers, but the fact is, they do a lot better job of monitoring a diver's condition, alerting to potential problems, (and collecting data in case of an accident) than a huge portion of the divers would do themselves.

I disagree with this. It's not fact. They don't monitor the divers condition at all. They simply take depth and time and run it through some equations. At that, most are using models that many of us feel are obsolete and wouldn't dream of actually using. There just now starting to slowly impliment some of the stuff that divers have been doing for years.

In any event, it's just a computer, and doesn't have a shock-collar attached, so if it locks out because of something that happened, but you still want to dive, nothing prevents you from grabbing an SPG, depth-guage and watch and going in again.

Terry

Except that if you're using the computer as your primary source of decompression information you'll be lost on the next dive if you try to do it with a depth gauge and a watch.

Like I say, I used to use one until I realized that I just didn't need it.

 

[MikeFerrara]

This is not totally true, with some computers if you know what you are doing you can adjust the conservatism from day to day or from dive to dive if you want. So say yesterday you were feeling great, drop the conservatism down. Today you feel a little tired, increase the conservatism a lillte bit.

But how does the computer apply conservatism? We don't just shorten or lengthen the NDL we reshape the whole ascent curve.