Sharing a Dive Computer

[The Chairman]

The answer to sharing a computer is absolutely NO from every agency and every manufacturer.

The above statement is about as true as a mask on the forehead indicating that you are a diver in distress. The OW standards for SDI requires at least one PDC for each buddy pair. Now that we established that you will not surely die if you share a PDC, let's look at some of the issues you will need to deal with, all of which deal with depth and time.

• No "SOB" diving. You simply can't afford to be Same Ocean Buddies for this to work. You should be within 5 ft of your buddy all the time. This is usually not an issue for married divers who often hold hands during the dive.
• Determine your limits before you dive (time, depth and air) and stick to them!
• Match your gas! Your gas should be the same.
• No riding the NDL. Keep your dive profile conservative and avoid going into the yellow zone.
• Increase your safety stop to 5:00 @ 15-20fsw. I also recommend a deep stop for 3:00 at half your depth if your depth exceeds 70fsw.
• Watch your air! Don't get so focused on these other details that you neglect this aspect of your dive.

Is this ideal? No. I prefer for each buddy to have their own PDC. That way, if a PDC fails, you both still have a back-up. Is it dangerous or fool hardy? No. The agency that pioneered dive training using PDCs accepts it as adequate during training. However, if you don't feel comfortable sharing a PDC: DON'T DO IT!

 

[NCadiver]

Netdoc you should not be encourage these new divers to pickup bad habits. You have no idea how well oddible and his wife dive together or how skilled they are. Base on their Padi training and the computer manufacture warnings buddy pairs are not to share a computer. SDI the new kid on the block is contradicting the dive computer manufactures, Padi, SSI, Naui.

 

[rstofer]

The above statement is about as true as a mask on the forehead indicating that you are a diver in distress.

I stand corrected! There is an agency that allows sharing a computer. Any others?

Now, is there any manufacturer that goes along with this? Probably not, they want to sell computers.

Richard

 

[The Chairman]

Netdoc you should not be encourage these new divers to pickup bad habits.

Nor should you be discouraging them from diving! :homealone:

Each of us has to come to our own conclusions on what is acceptable and not acceptable. A major training agency that has been the leader for online training as well as learning how to actually use a PDC during dive training has no problem with this and neither do I. Both of these areas were anathema to ALL of the training agencies not long ago, and now they are s-l-o-w-l-y coming around to see the logic and the inherent safety in accepting these paradigms. You can trust those that follow the leader here: I will continue to trust the leader.

Have fun with your computer and go dive. The sky is not falling and you will not surely die. I dove just this last week with a buddy on a single computer, and am here to tell the tale.

 

[TMHeimer]

I would never dive using a buddy's computer. That's just me. So far, most of my dives have not been multi level, so I really have used the max depth on the tables to go by, and the computer as a safety backup (the ascent alarm, info. for the log book, etc.). Having said that, I can see the possibility that the agencies/shops do have an interest in selling them to every diver.

 

[scubafanatic]

I went back and re-read every post, didn't see where it said you must dive with a computer. I read if you dive with a computer don't share. If you both WANT, not NEED, a computer rent one, don't share. You are correct, you do not need a computer to dive. You may use tables if you wish but you will have a square profile and unfortunately dives are usually not square. A very simple way to look at it is a computer is an optional (not in my world) safety device which helps you safely increase bottom time, monitor depth change rates, and determine SIT time based on off gasing tissue algorithms. While a computer may be optional to the diver, as the PADI book states, it is a requirement at several resorts and dive boats.

....most of the dive ops/boats I do business with .....MANDATE......as in REQUIRE computers.......and one computer PER DIVER !!! ......it's gonna suck if you fly all the way to some remote/ expensive dive location and you're not allowed to go into the water !

...there are even a few dive ops that will loan you a FREE computer (Dive with Martin/Cozumel)...that's how important some dive ops believe each diver having a computer to be.

...additionally, just like people can judge you by first impressions, dive ops will look you over (and you gear...or lack thereof) and make a preliminary opinion of you....let's just say you will be labled 'clueless newbie' and steered toward the 30 min @ 30' discover scuba/kiddie dives and kept well clear of anything remotely interesting/challenging.

......you can probably look forward to being 'outcasts' among the group....so the two of you need to make plans to rent your own local DM so the three of you can do your own thing.....all of you diving tables. The rest of the group will be on computers and will have much longer/deeper profiles than you will...and the rest of the group will not tolerate having to surface all because YOU have to surface while they still all have plenty of bottom time left......many ops have the group surface together due to local conditions, and you will be the weak link in the chain....wrecking the dive vacations of all the other divers that you will force to be shortchanged on their dive times!

...also, although you might be the exception, a dive computer is much less likely to make a deco/bottom time claculation error...compared to a diver having to manually calculate 'tables'......and if you screw up and get yourself bent in some remote location, will you be able to afford the air-evacuation/medical bills......and are you SURE your insurance would cover this eventuality, especially if they can say you were reckless and diving outside established safe practices ?

 

[TSandM]

I can imagine circumstances where it wouldn't be a big deal for one team member to have a computer, and the other simply a depth gauge/timer. But it would take an extraordinary situation for me to think it was okay for one diver to be in the water without a way of knowing depth or time. (The exception would be a site like our Edmonds Underwater Park, where the maximum depth in the whole park is 40 feet, and you could dive there for years on just an SPG.)

Pete, does SDI condone having one diver without any gauge at all?

 

[Peter Guy]

OP -- THE "book answer" to this question (with a nod to NetDoc) is "Do not share" a dive computer. Interestingly enough, however, the "book answer" to the question of "Which dive computer should my buddy and I follow when buddies have different computers?" is "the most conservative computer." Pray tell, how is that different from the team diving one computer if the book answer is to ignore your computer (if it is not the most conservative)?

I also find these discussions to be interesting, NOT for the answers but for the lack of thought in most of the answers.

There are MANY reasons why each teammate/buddy should have a dive computer and, in fact, have the same one -- and that is what I advise anyone who asks me. Then you have redundancy (always a good thing when in an alien environment), you each have appropriate information, etc. But, in reality, will it make your diving safer? Honestly, probably not -- assuming you dive safely anyway.

IF you choose to "take the risk" and have one computer for the dive team, go ahead knowing you have increased your risk by some (probably insignificant) amount. BUT, this advice DOES assume you will have minimal instrumentation -- depth gauge, SPG and watch. IF you do however, the increased cost of each having their own computer becomes so small as to why not each have one?

In sum, there just aren't many significant reasons NOT to have a simple dive computer. If cost is an issue, just make sure you have a simple SPG (about $50) so you'll know your pressure and a simple wrist computer ($200). You'll probably be better off this way.

 

[Mitchell]

Let's remember that he going on a vacation. The small cost of a dive computer should not be an issue. I'm sure he can shop around and get a good deal on one.

 

[Interceptor121]

I agree with NetDoc that we need to be realistic
After all how many divers you see without a computer and without tables?
I am not aware of any dive operation that checks if the guests have tables and know how to use them, besides to do a decent dive plan below 60 feet you need to do multilevel and majority of the divers have no idea how to plan and monitor the dive.
On the other hand if you and your wife are serious about diving then you really should have both an own computer sooner or later because it is just better to have your own