Dive Tables VS Dive Computer

[Chavodel8en]

Hi Rosevb,

Generally, computers are so cheap nowadays that its the easiest option. And it will expand your diving options, should you want to dive deeper. You can look on leisurepro.com, Amazon or other websites and get a ~$150-175 computer (new, can be cheaper used) that will take care of your needs. Make sure you understand the computers procedures - what all the numbers tell you and how you need to respond.

One note - you should NEVER rely on someone else's computer to determine your dives. You should be tracking your own dive, with whatever method you choose.

If you plan to only dive shallow, tables are a good option. When I started diving, since I already had a depth gauge (came with my used reg), I just bought a $30 watch and relied on tables. I was only diving shallow shore sites, so it was fine. And I was trained on tables, so I knew what I was doing. However, when I had a vacation planned, with deeper dives available, I bought a computer, as it will give you more dive time compared to tables.

And I would recommend that you should understand the basics of recreational, no mandatory decompression diving. I personally don't need to know all the ins and outs of "bubble theory" and I don't need to know the science behind our dive procedures.etc. etc.. But I know the basics of why I need to ascend at certain times and what risks I incur if I don't ascend.

Have fun!

 

[Marie13]

Rose - If you’re on FB, check out the Girls that Scuba closed group.

 

[W W Meixner]

Hi! I'm a very new diver, I just completed my open water this past summer and I have only been out twice since. In my training, we weren't really taught how to monitor our own nitrogen levels (we learned about it in theory, but just relied on the DM's computer while in the water) so I'm a bit confused now that it is actually up to me. Many people talk about how using the dive tables is a basic and cheaper option, but (forgive me that this sounds very dumb, I know) doesn't that mean you need a dive watch? The only ones I have been able to find are nearly as expensive as a dive computer, so then why would anyone encourage learning "the basics" and diving with the eRDPml or tables? Not sure if I'm missing something here... and we were never encouraged to go out and buy a dive watch so what are they expecting that we do?

Rose...

I have no idea what is being taught today...but back in ''the day'' not knowing how to use your RDP...(recreational dive planner)...which was an extensive part of your OW training...would fail you on a typical OW exam...

Find somone who was trained...25/30 years ago to sit down with you and go over a standard...as well as NITROX RDP...

You'll pick it up quick...and the knowledge is invaluable...and if you use it as a back-up check...you won't forget what you've learned...depending on computer selection...it may be more conservative than the tables...follow the most conservative...

So many ''new'' divers today have a full understanding of what their computer is telling them but absolutely no reason why...nor do they know and understand what's going on inside their body during the dive...

The attached photos show standard...and standard NITROX RDP's...

The small yellow RDP was developed buy a Canadian a long time ago who regularly dove the Tobermory wrecks...it's a short form NDL table...''a little beauty''...I highly doubt you'll find it anywhere now...the one I have was copy-righted by Gain Wong in 1994...

As far as a computer for you...a Suunto Zoop Novo/Mares Puck...or similar inexpensive air/NITROX computer of your choice will serve your current needs very well...

Hope this helps you...

All the best...and congratulations on your certification...

Warren...

 

[gr8jab]

I think the totality of the scubaboard community, and the skills and understanding of scuba herein, skews the perspective of many of its members.

I work among a lot of extremely smart people. My coworkers all have Masters and PhD educations. Certain comprehension, knowledge, experience, and inherent intelligence is a foregone conclusion where I work. I often question my work, skills, and capabilities in this environment. It can be somewhat demoralizing. Then I go to Walmart for groceries. Looking around reminds me that I'm not so far down the tail of the distribution as I had felt. Scubaboard is like my office (a small group of very smart people), and the majority of scuba divers are people a Walmart (some smart, but some not so much).

My point is that here on Scubaboard it is expected that most of us understand dive tables, internalize what they describe physiologically, and why they work. Furthermore, most of us comprehend how dive computers work and act as accumulative real-time high resolution digital tables. HOWEVER, we forget that we are not NORMAL. Most normal students do not get it. Most students who learned dive tables are churn-n-burn, not really understanding what they are doing. It's cookie-cutter scuba. I'm not commenting on the state of scuba education, commercialization of certification agencies, or watering down of the curriculum. Let's avoid that rat-hole.

I do not believe that learning tables helps 90% of the students understand the physiology of diving. It takes considerable time and effort to teach students to use them, after which they know how to follow the rows and columns and write a few letters or numbers on paper, but lack any real understanding of what they are doing. If the goal a complete technical understanding, teach the Ideal Gas Law and Waals State Equations, not cookie-cutter dive tables.

99% of divers use computers. Using tables as a bridge or teaching tool is unnecessary and confusing. I advocate a computer-only curriculum where time is spent explaining the physiology and how it relates to typical computer features. Bolster the discussion of NDL, nitrogen loading, and dive planning with a computer focus. If most students comprehend and remember NDL, we should be happy! If they are going to be cookie-cutter students, it should be computer cookie-cutters. Scare the crap out of them with a bottle of warm soda pop, so they learn not to ignore their computers, and be done with it. 99% of them will not want or need more. Those 1% who do can seek out more training (be it DIR or Deco or reading Scubaboard).

All this is said in a calm and conversational tone. Feel free to tell me I'm wrong, but do it politely please.

 

[gr8jab]

Rosevb: Welcome. Don't let us scare you away. Read past the banter and find the good nuggets of information. Here's what I think about your original question.

1. Buy and use a dive computer.
2. Use tables if you want, many do. The dive computer will make a GREAT depth gauge and timer too.
3. Be curious and learn more about diving if you want. It will benefit you.

 

[tursiops]

I think the totality of the scubaboard community, and the skills and understanding of scuba herein, skews the perspective of many of its members.

I work among a lot of extremely smart people. My coworkers all have Masters and PhD educations. Certain comprehension, knowledge, experience, and inherent intelligence is a foregone conclusion where I work. I often question my work, skills, and capabilities in this environment. It can be somewhat demoralizing. Then I go to Walmart for groceries. Looking around reminds me that I'm not so far down the tail of the distribution as I had felt. Scubaboard is like my office (a small group of very smart people), and the majority of scuba divers are people a Walmart (some smart, but some not so much).

My point is that here on Scubaboard it is expected that most of us understand dive tables, internalize what they describe physiologically, and why they work. Furthermore, most of us comprehend how dive computers work and act as accumulative real-time high resolution digital tables. HOWEVER, we forget that we are not NORMAL. Most normal students do not get it. Most students who learned dive tables are churn-n-burn, not really understanding what they are doing. It's cookie-cutter scuba. I'm not commenting on the state of scuba education, commercialization of certification agencies, or watering down of the curriculum. Let's avoid that rat-hole.

I do not believe that learning tables helps 90% of the students understand the physiology of diving. It takes considerable time and effort to teach students to use them, after which they know how to follow the rows and columns and write a few letters or numbers on paper, but lack any real understanding of what they are doing. If the goal a complete technical understanding, teach the Ideal Gas Law and Waals State Equations, not cookie-cutter dive tables.

99% of divers use computers. Using tables as a bridge or teaching tool is unnecessary and confusing. I advocate a computer-only curriculum where time is spend explaining the physiology and how it relates to typical computer features. Bolster the discussion of NDL, nitrogen loading, and dive planning with a computer focus. If most students comprehend and remember NDL, we should be happy! If they are going to be cookie-cutter students, it should be computer cookie-cutters. Scare the crap out them with a bottle of warm soda pop, so they learn not to ignore their computers, and be done with it. 99% of them will not want or need more. Those 1% who do can seek out more training (be it DIR or Deco or reading Scubaboard).

All this is said in a calm and conversational tone. Feel free to tell me I'm wrong, but do it politely please.

Well said.
I watched my wife teach "deco theory" and "tables" in a scuba class once. She used a credit-card analogy....you go on a dive and that's like charging stuff on your card. Your card has a limit so you can't charge too much; that's like the NDL. When you surface your SI is like paying off the card, a little at a time; if you don't pay it all off, you can't charge as much on your next shopping trip; that's the residual nitrogen. She introduced all the terms and concepts with the credit card analogy. someone asked, but how do we calculate that for our diving? She said you can use the tables, or a computer. By then, people had figured out the basic concepts and had not been burdened with things they didn't really need to know. i was pretty darn impressed.

 

[TMHeimer]

Considering the title, I just can't read all posts.
---Tables: You need watch (timer if you will) and depth gauge. I've bought watches for $25-30 that have lasted years (well, I LOST 2 of the 3 so far).
---Computer--needed for true multi-level dives. Some use 2 (a backup), some like me use computer and analog (watch/depth gauge/tables).
Computers don't have the "rounding" benefit of tables. Your (theoretical) bottom remaining is "exact"--no little bit of extra time like most likely with tables.
---Analog stuff is fine for square profile dives (basically one depth the whole time-- like 4 feet off the bottom).
---The eRDPML is basically useless (IMO) unless you know that you will be spending pretty exact specific times at specific levels. You can't plan something with it and then like, stay 10 minutes more than planned at 70'. You can't descend to 100' on a wall dive and gradually ascend. Well, of course you CAN by looking at your computer, but you can't plan anything like that ahead of time on the eRDPML. You can use it as a tool to figure out dive profile problems, so I guess it can be of a little value there.

 

[Celt]

There is no “tables versus computer” they compliment each other. Get yourself a nice computer but run through the tables pre dive and go through the various options for the dive. Always plan the dive, never get in the water without a plan.

 

[arcticat99]

also computers are not perfect either .i read a post here a while back of a lady that panicked because her computer gave her a ridiculous safety stop time and she was a seasoned diver.a pre dive check with charts should of told her the computer was acting up and to trust judgement .if i recall it wasn't a very deep dive and her computer wanted a 90 minute safety stop obviously she wouldn't have that much air left

 

[Kamaros]

Just get a computer. The cost of an entry level computer isn't too far removed from that of a depth gauge and timer, and many boats the days require that you use a computer while diving.

As for my two cents on the whole tables vs computers debate, I do think that tables are mostly obsolete in this day and age. An analogy was made earlier comparing computers to calculators and tables to basic arithmetic, but I think a better analogy would be comparing computers to calculators and tables to slide rules. Learning to use tables still doesn't automatically teach you about the mechanisms of on- and off-gassing, saturation, partial pressures, M-values, tissue compartments, etc. In the end, the table is still just a tool that lets you calculate NDL times for certain depths and surface intervals. Given that computers will usually provide longer NDLs for the same dive, I just don't see many advantages to using tables over computers if both are available.

There's some argument to be made about the benefits of using tables if you're paranoid about computer malfunctions, but I also think that most of the risk is mitigated by bringing a backup computer.