Are dive computers making bad divers?

[Nasser]

The premise that any tool can make you bad at something is IMHO essentially flawed. It is how one chooses to use that tool that will ultimately determine the end result. If you have either received poor instruction, acquired bad habits along the way, or are relying on a specific tool to the point that it becomes a crutch and renders you useless without it (barring essential life support, like a regulator! ... then that's essentially your fault not the tool's.

This is the double edged sword that is technology and it's probably a good thing to keep in mind when enjoying it's benefits.

 

[scubadada]

Ratio Deco is fantasy based at best. More divers, per capita, get bent on that, than any PDC or other table. Probably all of them combined.

Hi Pete,

Is that right? Do you think this is related to the method or the implementation? I've been very interested in the decompression algorithm or method used and the association with DCS but have not been able to find data. I thought that some of this might be coming out from DAN's Project Dive Exploration, at least with regard to computer use, but have not seen anything.

I do not know much about Ratio Deco, but have read that it roughly correlates with Buhlmann ZHL-16C 30-40/85, that's reasonably conservative. The DSAT algorithm/PADI tables seem to correlate with something like 45/95, more liberal.

Good diving, Craig

 

[The Chairman]

Is that right?

While I was at DEMA, I got to sit down with one of the former researchers for DAN. I had noticed that there was a lot of denial about ratio deco on ScubaBoard by it's adherents. There's a lot of ongoing mental calculations that are done, some of which are done in the narc'ed zone, where it's easy to make a simple mistake with not so simple results. He confirmed that ratio deco presented far more bends than the amount of people actually using it would suggest. Far more.

As was suggested by the bhb troll, your instructor makes all the difference. All tools have benefits and limitations. For most tools, the biggest limitation lies with the user. Abuse the tool and you will lose the tool. You might lose something else at the same time. Hopefully, your instructor well help you to become competent with your tool set, understanding all of its limitations.

 

[kensuf]

However, just because some of them now have a computer strapped to their wrist, that does not mean they have stopped properly planning their dives. In the DIR mindset, you have your dive well planned before you get in the water. Part of that planning includes having a set of tables that are cut for the planned depth and time, plus a few contingency depths/times, and you should also understand how the tables are formulated so that in the event that your dive drastically deviates from the plan, you can adjust them as needed. In true DIR fashion, you should have a pretty solid understanding of how long your dive will be before you ever get wet.

I don't know any training agency that does not advocate the same thing. Technical divers who have never heard of DIR (and, believe it or not, there are many) have the same mindset.

I teach technical diving for two agencies. Both teach creating a thorough dive plan before entering the water. Both teach creating a pre-designed profile and contingencies before you get in the water. When I do deco diving from a boat during my winters in South Florida, before we hit the water the boat crew goes around the deck asking each team what their planned run time is. Now, I don't know what training each team has, but every one of them has obviously planned the dive ahead, and it sure looks to me as if just about every one of them is carrying a computer. The shop I usually use for these dives is GUE-affiliated.

How the dives differ, I imagine, is in what happens under water. If you have a pre-planned strategy, written contingencies, and a computer that is programmed to give the same plan, how to you use all of that? Some people follow the plan strictly, using the computer only if something forces them far enough away from those plans that they prefer to follow the computer. Others follow the computer, planning to use the written plans (with their backup gauges) only if the computer fails. I think the trend in my personal observations is to the latter, especially since people tend to plan to the worst case scenarios and are likely to have done a shallower dive than their written plans called for.

So my response was to the question about the DIR/GUE crowd. But to go back to the original post that started this thread, IMHO, sloppy instructors are to blame for making bad divers.

All dives, whether it is a 20' lookie loo dive in warm clear water, or a 15,000' penetration into a 300' deep cave, should have three limiting factors established prior to hitting the water: maximum depth, gas turn-around pressure, and finally, maximum time (turn-around time).

A computer is not to blame for people not establishing those three limits. Every computer I have ever used (going back to the first Oceanic computer I bought in 1993) has a dive planning mode that showed you the various NDL's for various depths, it should be a simple matter to look at the dive planning mode and establish your time limit before you hit the water.

It's simply piss poor form to tell someone "here, just strap this on your wrist, and when it says you're down to 1 minutes remaining, begin your ascent."

 

[Rhone Man]

If I was to paraphrase this thread to an alien sociologist from another planet I would say: "In this field of human activity, a new invention has become popular and cheap. Although it seems to be pretty effective, older generations complain that people have lost the ability to do things 'the old fashioned way' and as a result they are less skilled."

I am pretty sure that the alien would nod and day "Yeah, we see that kind of thing a lot on your planet."

The reality is that people were always sucky at tables (except for a few hard core divers), and the tables were extremely inaccurate anyhow (except for one dive in a hundred where you actually did a square profile). When PADI invented "the wheel", that was more accurate but took more skill to use, but I don't recall too many old timers running around telling everyone that they had to learn how to use it as it would make them better and safer divers.

Dive computers are cheap, safe and reliable, and if a generation of divers just want to just ride their computers, well so far that doesn't seem to be resulting in too many diving deaths. In the same way that many car drivers lost the ability to steer into skids when ABS became ubiquitous on cars, that doesn't mean that driving in slippery conditions became less safe.

YMMV.

 

[Reku]

You have had 10 computer failures? We're these people buddies, random divers or what? How much deco was stopping them surfacing?

EDIT: Don't dive alone unless you are prepared to save yourself using only what you have on you and what you have learned (and are prepared to dive alone if you can't.). I'm not advocating solo diving for the average diver.

4 were buddies (computer failures without them realizing it failed (3 sherwood wisdoms and a cobalt atomic) all ai integrated) and 6 were random strangers (computers worked but did not have enough air to last the deco) I happen to find while under. Honestly I don't know what they were thinking, the average deco on those 6 divers was like 12mins, enough time to be life threatening. I'm only 25 and at this rate I will eventually see someone get bent/die in my lifetime. I feel the only way to dive with a buddy is to keep watch on their systems (spg+computer) at all times and honestly if I'm doing that how will I ever enjoy the dive. Dive buddies/other divers stress me out. I must have the worst dive luck ever. Oh well diving is life and I'll just keep on doing it.

 

[phoenix31tt]

sounds like some bad practices overall:

4 were buddies (computer failures without them realizing it failed (3 sherwood wisdoms and a cobalt atomic) all ai integrated)

computer failures without them noticing? how does one not notice a computer failure... what kind of failure was it?

and 6 were random strangers (computers worked but did not have enough air to last the deco) I happen to find while under. Honestly I don't know what they were thinking, the average deco on those 6 divers was like 12mins, enough time to be life threatening.

well... this one is just outright horrible dive plan or none at all... and has nothing to do with computers

 

[Eric Sedletzky]

I feel the only way to dive with a buddy is to keep watch on their systems (spg+computer) at all times and honestly if I'm doing that how will I ever enjoy the dive. Dive buddies/other divers stress me out. I must have the worst dive luck ever. Oh well diving is life and I'll just keep on doing it.

This is the main reason why I started solo diving and gave up on finding competent buddies.
Training is supposed to be about standardization throughout the whole industry, not just premier agencies like GUE.
I found that to be untrue in most of the regular recreational divers I've buddied up with over the years. I don't think computers made any difference either way, they would probably be even worse diving tables.

 

[Reku]

sounds like some bad practices overall:



computer failures without them noticing? how does one not notice a computer failure... what kind of failure was it?


well... this one is just outright horrible dive plan or none at all... and has nothing to do with computers

3 of the computers were not reading the pressure correctly at all (telling them they had more gas then they did.) and the atomics screen was just frozen in place. I have NO IDEA what those people did to their computers.

As for the bad planning - these people are on the do not dive with list. It was just stupid. (I asked the groups they were with who they were, then promptly added them to the list.). Yes it was not really computer related but I think that if they were less reliant on the computer they would of had better safety practices overall. IDK just my thoughts, I'm probably wrong.

 

[scubadada]

While I was at DEMA, I got to sit down with one of the former researchers for DAN. I had noticed that there was a lot of denial about ratio deco on ScubaBoard by it's adherents. There's a lot of ongoing mental calculations that are done, some of which are done in the narc'ed zone, where it's easy to make a simple mistake with not so simple results. He confirmed that ratio deco presented far more bends than the amount of people actually using it would suggest. Far more.

As was suggested by the bhb troll, your instructor makes all the difference. All tools have benefits and limitations. For most tools, the biggest limitation lies with the user. Abuse the tool and you will lose the tool. You might lose something else at the same time. Hopefully, your instructor well help you to become competent with your tool set, understanding all of its limitations.

Is there any published data to back this up?