Sharing a Dive Computer

[syntaxerrorsix]

Fear is far more motivating and fun than actual science and research. The industry needs far less of the "sky is falling" mentality and a healthy dose of reality to get past the fear mongers.

At one time NitrOx was referred to as "voodoo gas" by the same type of people. This is just more of the same obstructionist/ head-in-the-sand thinking.

That's a patently ridiculous statement comparing apples and orange. We are not going to find out later on down the road that each diver really doesn't have to monitor his environmental concerns.

I see you have a dangerous idea of what change versus improvement is.

 

[The Chairman]

Fact - PADI trained

Again, you assume a lot and overlook the rest: PADI trained does not indicate that they know how to use tables. They might have been trained only on PDCs or the eRDP... we just don't know. Yes, your assumption, might be correct, but it is still an assumption loosely based on a fact. Here's a question for you: how many watches and depth gauges are required for a PADI OW class? Cite your source.

Fact - Doesn't know how to use one computer with a buddy.

Obviously, you don't either. Here is an opportunity to learn something. In fact, he does not claim to be unable to use the PDC with his partner, he is looking for some input on areas to look out for. Let's answer his question, shall we?

Reasoning - Wouldn't be here if he already had the answer.

Your entire argument revolves around the premise that it's dangerous to learn new techniques on the internet, which begs the question: why aren't ScubaBoarders dying in record numbers? ScubaBoard is probably the finest source on the internet to learn about new ideas and to refine some old ones. Even you come here... why?

Data - Far more literature than I care to post here from nearly every dive agency in the world and nearly every computer user guide published.

Shenanigans. Literature does not equal data.

Knee jerk - Your idea to toss new divers into an unknown situation they haven't trained and practiced for because you and one or two agencies train THEIR divers to do this.

No, that's simply not true. I demonstrated that the axiom that "no agency" promotes this is fallacious and suggested that the ire comes from a "sky is falling" mentality. I even answered the man's questions thoughtfully, which most did not. You might be opposed to giving people what they actually want, but I am dedicated to it.

Any things to be wary of or to take into account when sharing a computer with your dive partner?

The knee jerk mentality comes from the inability of a few to make adjustments to incorporate new training techniques into their diving. They clamor for the status quo and portend that if you depart from these antiquated concepts "you will surely die".

One of the biggest problems in our industry is the "dive my way, or it's crap" mentality. Many dive shops relied on this before the internet to keep their customers loyal. "Don't buy Brand Z because it's CRAP! We don't carry crap, ergo that must be the reason we don't carry Brand Z". On the internet, people who disagree with you, are "patently ridiculous" and have a "dangerous idea". It's just more "dive my way or it's crap" mentality. Here's a clue, and you don't even need to buy it: There are a lot of gear configurations out there that you won't/don't understand and people are not going to die because they don't dive your way.

 

[syntaxerrorsix]

Again, you assume a lot and overlook the rest: PADI trained does not indicate that they know how to use tables. They might have been trained only on PDCs or the eRDP... we just don't know. Yes, your assumption, might be correct, but it is still an assumption loosely based on a fact.

You presume either or. It's apparent PDC wasn't covered or he wouldn't have proposed the question. That leaves one option. Not an assumption, a process of elimination.

Here's a question for you: how many watches and depth gauges are required for a PADI OW class? Cite your source.

Irrelevant. We know that each diver must be aware of time and depth. This is not a buddy event nor is it taught that way.

Obviously, you don't either. Here is an opportunity to learn something. In fact, he does not claim to be unable to use the PDC with his partner, he is looking for some input on areas to look out for. Let's answer his question, shall we?

The questions was, "Since we will be doing all of our diving together I suspect that while not ideal that this isn't too big a problem. Any things to be wary of or to take into account when sharing a computer with your dive partner?" We answered it by confirming it is not ideal nor recommended. It is typical not to offer advise on something you advise against. Simply stating the reasons why it is ill-advised is commonplace.

Your entire argument revolves around the premise that it's dangerous to learn new techniques on the internet, which begs the question: why aren't ScubaBoarders dying in record numbers? ScubaBoard is probably the finest source on the internet to learn about new ideas and to refine some old ones. Even you come here... why?

My entire argument is based in the logical conclusion that the diver should not be subjected to technique that he is unfamiliar with and SHOULD use the one he was taught. This is especially true for a new diver until he has the experience to make changes to well founded techniques. Your method does not improve the safety of the diver but it could certainly jeopardize it. That's the difference between change and improvement. You offered no improvement.

Shenanigans. Literature does not equal data.

Empirical evidence trumps follow the leader every time.

No, that's simply not true. I demonstrated that the axiom that "no agency" promotes this is fallacious and suggested that the ire comes from a "sky is falling" mentality. I even answered the man's questions thoughtfully, which most did not. You might be opposed to giving people what they actually want, but I am dedicated to it.

I suggested he use the tables he was taught with. ( covered the presumption part earlier.) That is the safest most reliable path for the new divers. You interjected with an opinion based off your experience not the individual divers experience.

The knee jerk mentality comes from the inability of a few to make adjustments to incorporate new training techniques into their diving. They clamor for the status quo and portend that if you depart from these antiquated concepts "you will surely die".

Once again your small adjustment does not in anyway improve the safety of the divers. It has little to do with status quo and more to do with common sense.

One of the biggest problems in our industry is the "dive my way, or it's crap" mentality. Many dive shops relied on this before the internet to keep their customers loyal. "Don't buy Brand Z because it's CRAP! We don't carry crap, ergo that must be the reason we don't carry Brand Z". On the internet, people who disagree with you, are "patently ridiculous" and have a "dangerous idea". It's just more "dive my way or it's crap" mentality. Here's a clue, and you don't even need to buy it: There are a lot of gear configurations out there that you won't/don't understand and people are not going to die because they don't dive your way.

You can dive anyway you feel comfortable diving and you won't here a peep from me about it. What you will hear is my objection to giving new divers poor advise. You have not enhanced their skill level or increased their safety level. You proposed and idea that many frown upon for common sense reason. You then proceed to take a holier than thou "progressive attitude" and playground tactics while presuming everyone else just isn't up to speed.

I call shenanigans because it is. There is no good reason the couple should use a single computer when they can use tables and their own timing and depth device. If you can teach them how to use the PDC online you can also teach them to be self reliant with tables.

It appears we will have to disagree on this subject 100%

 

[Bonairetrip]

Not even close! Now he has a safe computer for most warm water scenarios (Veo 250) paired up with a computer designed to be used in cold water (Suunto) and they won't match. The latter will go into deco far before the former, so they will STILL be relying on the Gekko.

(Emphasis added.)

Now each diver will have their own computer and each diver will rely on their own computer. They are not both relying on the Gekko!

Of course, since the Suunto is more conservative, and if all other things are equal, it will be the Suunto that will limit bottom time and not the Veo.

All too often, in the real world, all other things end up not being equal. Diver A gets separated from diver B. Diver A descends first while diver B descends slower. One lingers longer than the other. One is distracted and floats down (or up) a bit. They might ascend at different rates, etc.

 

[oddible]

OK ok ok. Please stop, I'm really unhappy with the rising tension in this thread.

I now have a Suunto Gekko and a Oceanic Veo 250. It was indicated that this is a problem because they use different algorithms. I was aware of the different algorithms which is why I got a LESS conservative computer as a second computer rather than a more conservative computer - whether I have 2 Suuntos or 1 Suunto and 1 Oceanic I'm going to be diving by the Suunto's algorithm either way so I'm not sure why this is an issue - most certainly better than the 2nd person diving off tables. I live in Vancouver so I was recommended the Suunto for local diving where I'll be doing most of my dives, perhaps when I have the extra cash I'll buy 2 of each so we can use the Suuntos locally and the Oceanics in the tropics.

 

[rstofer]

The thing is, this debate (shared computers) rages every few weeks. You can get the same posts, from the same people, with the same opinions, by just using the Search feature.

Once they start, these threads take a while to burn out.

There are no 'original' questions on SB. Every subject repeats over varying periods of time.

Richard

 

[syntaxerrorsix]

OK ok ok. Please stop, I'm really unhappy with the rising tension in this thread.

I now have a Suunto Gekko and a Oceanic Veo 250. It was indicated that this is a problem because they use different algorithms. I was aware of the different algorithms which is why I got a LESS conservative computer as a second computer rather than a more conservative computer - whether I have 2 Suuntos or 1 Suunto and 1 Oceanic I'm going to be diving by the Suunto's algorithm either way so I'm not sure why this is an issue - most certainly better than the 2nd person diving off tables. I live in Vancouver so I was recommended the Suunto for local diving where I'll be doing most of my dives, perhaps when I have the extra cash I'll buy 2 of each so we can use the Suuntos locally and the Oceanics in the tropics.

As long as each of you can verify individual time at depth and plan for your next dive you should be in good shape.

 

[theskull]

Not even close! Now he has a safe computer for most warm water scenarios (Veo 250) paired up with a computer designed to be used in cold water (Suunto) and they won't match. The latter will go into deco far before the former, so they will STILL be relying on the Gekko.

Dude, now you're the one spreading myths and using scare tactics!

The issue is that each diver has his own timing/depth device. Noone suggests that all divers must use the same brand and algorithm!

You are better educated than to suggest otherwise. Both computers are good recreational computers. Both use conservative NDL. Both divers are individually well equipped, and if either device fails the team can safely complete the dive on the working unit.

Will the SUUNTO time out at depth before the Oceanic on an identical repetitive dive? Of course. So what? If either diver makes an additional dive or goes deeper on one of their dives to retrieve a dropped knife or take a photo, they will each have their own record and profile.

It is rare that I dive with other divers who all are using the same computer. The dive always gets called, as per training, when the most conservative unit times out at NDL (and to head off additional potshots- no, we don't wait until it times out, the dive is called when there are several minutes left of NDL at max depth).

theskull

 

[Peter Guy]

For those of you who are adamant that it is dangerous for a buddy pair to "share" a computer, will you please explain why it is dangerous?

Is it because:

a. One buddy doesn't have depth/time gauge? If she did, would it be OK?

b. One buddy won't know her decompression status?

c. Do you believe that the decompression algorithms used by "recreational computers" are precise enough to actually indicate a bright line between having a strong chance of DCS vs. a very minimal chance of DCS?

d. Do you believe it is ever safe for a buddy team to dive without any computer and without planning a table based dive? If so, under what conditions?

 

[theskull]

Sharing a computer is not dangerous, but is also not best practice.

a. If both buddies had depth/time gauge and the non-computer user knew the tables for the planned dive, it would be OK. This also assumes they are not planning multi-level dives, though, and this is pretty rare at most dive sites.

b. Deco status SHOULD be a non-issue in rec diving. Divers should stay well out of a deco obligation.

c. Rec computers have a most excellent record of keeping people free of DCS, even when making multiple days of repetitive dives. Tables do, too, but cut a lot of bottom time out of your multi-level dives. Nothing will guarantee freedom from DCS.

d. Non-computer non-table dives are certainly safe (as safe can be) when all dives will be less than 40 ft. depth. I personally would still want a record of time/depth for my logbook, though.

In my opinion the big issues here are not danger, but:

a. Using best practices for best safety both now and in the future through good habits.
b. The very small additional cost of equipping both divers with a computer (bought used or rented) to make the issue go away and provide a better experience for both.

theskull