PADI Nitrox, Computer vs. table class

[BigJimDiver]

I took the PADI Nitrox class last year while on a Liveaboard trip. Glad I did, but I quickly realized that with 5 dives a day the tables are essentially worthless since you dive on computer anyway. I tried to practice on the tables but quickly was off the charts.

I'm having my son take the class this year (just turned 15), and the local shop who is giving him the class asked if I wanted him to do the Computer version, or the table version. I thought learning the tables would be good to do as a back up in case a computer craps out on him on a trip some day; they seemed to steer me towards the computer class saying that's the way most dive these days anyway.

Any thoughts from those more experienced than me? Is taking the tables class a waste, or is there some down side to taking the tables class that I'm missing? Or would this be good experience even if he ends up always diving on computer, even though if he never uses the tables that knowledge may be forgotten anyway?

Lastly, they tell me that PADI has eliminated the multi level tables, but an eRDP is a good alternative (in case of computer failure), any thoughts on that?

 

[rjack321]

Tables, although I haven't dove a computer in 6yrs so I'm biased

 

[fisheater]

Tables.

That will teach him the underlying theory and he can always learn how to use a computer.

 

[Charlie99]

Many people think that learning by rote the mechanics of calculating deco by table teaches you something about decompression. I don't subscribe to that theory.

A class that has an informative discussion about computers, their operation, and their limitations would be a good one, if it exists.

An essential part of diving based upon a computer is having some way of doing a sanity check on what the computer is telling you. There are many different ways of doing that. Square profile tables aren't very good for that if you are doing dives that are very multilevel.

 

[h90]

I would say computer, but he should have a look at the tables himself.

 

[Crowley]

For the current PADI nitrox course, computers are mandatory, tables are optional.

The OW course can be taught with computers or tables. I always teach tables in OW because it helps to give a basic introduction to decompression theory. I am not a big fan of the eRDP-ML - it would have been a good idea 20 years ago but you can pick up a dive computer for $150 these days. An eRDP-ML + decent dive watch would cost about the same.

I think all divers should still know how to use the tables, or at least be taught how to use them; whether they continue to apply that knowledge is up to the diver, really. Practically speaking, most regular recreational divers invest in a basic dive computer and forget about the tables.

As for downsides to learning tables vs computers - the only real downside is that for deeper dives, your dive times will be significantly shorter than they would be if you were using a computer. NDL for 30m/100ft on the RDP is 20minutes. Multi-leveling will extend this of course but the rules of the multilevel eRDP and the old wheel mean that the levels at which you are required to remain would not be practical at many dive sites.

I recommend people learn the tables, keep them with their dive gear, continue to understand how they function, and purchase a dive computer.

Hope that helps

Cheers

C.

 

[Searcaigh]

Tables - they don't need batteries

 

[Jim Lapenta]

I teach tables and offer instruction on computers. I don;t sell computers and don;t even recommend them to my new students. I'd rather see them stay conservative and work on basic skills and good planning habits for every dive. As for nitrox I teach tables and will again offer instruction if the student has a computer or buys one during the class from somewhere. If they get one after I'll help them through it. Computer only presupposes that the diver actually plans on buying a computer. They don't have to. Frankly I see it as an unnecessary expense for the new diver. I feel they still need to know how to calculate MODS, EADS, and plan dives with tables. I also teach that they should calculate and make contingency plans should the dive profile change due to conditions, site, etc. For me that is easier to do with tables. Unfortunately the reality is many don't even bother to plan for contingencies because they allow a DM or someone else to plan the dives. ANd even at recreational levels and depths deco is not an exact science and the computers are not tracking individual physiological factors. Too much trust is generally given and that can get a diver into trouble if they do as many I see and push the comps to their limits, thinking as long as it's in the green or yellow they will be ok.

 

[DevonDiver]

I think that any of the current generation of divers who are not learning to dive with tables, will suffer a disadvantage as they progress to more advanced levels of diving - where tables are often used, even as back-ups.

Learning how to operate the tables on a nitrox course provides very positive reinforcement and practice in areas such as; EAD and MOD calculation.

We occasionally see questions here on SB from computer-only trained nitrox divers, which illustrates that they have a poor understanding about how to utilise the mathematical calculations needed to manually plan nitrox dives.

I'd say... if you have the option, learn with tables. How can more knowledge and practice hurt?

 

[mjatkins]

For the current PADI nitrox course, computers are mandatory, tables are optional.
C.

Can you give a little more information about this. Is it a recent standards change that I have missed? My manual does not say that computers are mandatory.

Thanks