Body check when you are on a single tank and your buddy on doubles

[Soakedlontra]

I guess this thread may be on the borderline between basic and advanced scuba discussions...

Recently I have been diving with a buddy who uses double tanks while I am on a single cylinder. I hardly know anything about doubles except that they have more valves, are heavier and, of course, have much more gas than my tank.

I am wondering if I should be aware of certain things that normally I would not need to know when I dive with single-tank-buddies while doing the body check.

If there is leak the only thing I would be able to do is to signal my buddy assuming that divers on doubles are trained to handle that situation by themselves...

 

[g1138]

First off I think it's a really bad idea to dive with two different tank set ups.
Granted it's not like two buddies diving with different gas mixes, but still I can't imagine your SAC rates are that far apart.
Is there any reason why your buddy chooses to dive with doubles?

In any case I've never dove with doubles, so I can't add any personal input.

This question however should definitely be asked to your buddy. If he's diving doubles, then he should know how to use them. Therefore he should be able to tell you what he expects as a efficient buddy check.

You may want to ask this on the technical board as well if you want more input. I think those guys will be much more helpful. =]

 

[a22shady]

I would say it's no big deal. There are people who dive different set-ups all the time. What you need to establish is what to do in OOA emergency. If they are on a Long/Short hose set-up they would donate there primary to you. Other then that I dont see much concern. If you see something leaking you notify the buddy what goin on and yes they can generally take care of it. Either way you end the dive safely and get it fixed on the surface just as you would single tank.

 

[tkdgodess]

I dove with a buddy who wears twin 100's, and I wear a single steel 130. He dove DIR style, I don't. We did our Predive Safety Check based on our gear for that day, OOA procedures (like that would happen - ok gear failure).

As long as it's included in your dive plan and discussed it's no big deal, I don't see what the fuss is about not diving gear exactly the same on recreational non-deco dives where a direct ascent to the surface at any point during the dive is an option.

 

[Superlyte27]

I just sold my single b/c. I guess that means I exclusively dive doubles now. There's no difference in the buddy check. Check for leaks from the regulators, tanks, inflator/deflator hose, etc.

Should there be in issue in the water, options are more abundant. You can isolate the issue, or shut down the issue. But, your buddy should know what he wants and should be able to remedy this issue himself.

 

[Soakedlontra]

First off I think it's a really bad idea to dive with two different tank set ups.
Granted it's not like two buddies diving with different gas mixes, but still I can't imagine your SAC rates are that far apart.
Is there any reason why your buddy chooses to dive with doubles?

In any case I've never dove with doubles, so I can't add any personal input.

This question however should definitely be asked to your buddy. If he's diving doubles, then he should know how to use them. Therefore he should be able to tell you what he expects as a efficient buddy check.

You may want to ask this on the technical board as well if you want more input. I think those guys will be much more helpful. =]

My buddy has just passed a Tech 1 class and she wants to practice diving with doubles while carrying a deco bottle at the same time. Our max depth in our dives is about 60 ft so the NDL is not an issue because it is not my style of diving stretching the limit of my bottom time until I get into deco and regarding her she can practice going into deco with her fellow Tech buddies.

Sometimes things don't come up right there when the action is going on, but later when my brain has time to wondering around and pondering on what I did, happened etc...

Just reading the few replies here has made me think of things that I have not thought before...Thanks folks!

 

[DevonDiver]

I guess this thread may be on the borderline between basic and advanced scuba discussions...

Nope. Wearing doubles is a perfectly valid recreational diving configuration. Depending on how they are used, there can be very little difference between doubles and single cylinder procedures.

Recently I have been diving with a buddy who uses double tanks while I am on a single cylinder. I hardly know anything about doubles except that they have more valves, are heavier and, of course, have much more gas than my tank..

Yes...two valves to turn on... the same as a single cylinder. No brainer. There may be an isolation valve between the tanks, but you shouldn't ever need to touch that unless he asks. The two regulators coming from the tanks should be checked just the same as the primary and octopus/aas that you use. He will have an SPG, just like you, and it should read just like your SPG.

I am wondering if I should be aware of certain things that normally I would not need to know when I dive with single-tank-buddies while doing the body check. .

He should be the person to make you aware of everything. If he doesn't then you should ask. The purpose of the buddy check is it ensure that both divers understand each other's kit.... and to confirm that this kit works.

It's no stress to dive with a doubles diver.... but you DO need to do a very comprehensive buddy check first.

No offense, but to be asking this question having already dived with him, it sounds like you have been neglecting this?

If there is leak the only thing I would be able to do is to signal my buddy assuming that divers on doubles are trained to handle that situation by themselves...

Don't assume anything. Plan and confirm everything you can think of before you get in the water.

 

[Dr Wu]

First off I think it's a really bad idea to dive with two different tank set ups.


In any case I've never dove with doubles, so I can't add any personal input.

I you don't know anything about doubles how can you say it's a really bad idea to dive with someone using them?

 

[g1138]

I you don't know anything about doubles how can you say it's a really bad idea to dive with someone using them?

The fact that it holds so much more air and is entirely different in my perspective as to say diving on a single tank.
In my view diving doubles would be for tech or long range diving. Which entails using different view points, different dive plans, different thoughts as to say recreational diving. The buddy with more air has the ability to dive deeper and longer, the potential dive profiles are a lot more expanse than someone diving a single tank.
It's a huge difference in my mind.

In a sense I'm falling back on DIR's standpoint of having exactly the same gear. I don't follow this strictly per-say but I think it's a good idea to have similar equipment or equipment that you can familiarize yourself with.

After the OP stated the buddy's reasons, I kinda warmed up to the idea. But I still think a buddy team should dive the same tanks and the same mix; stick to a turn around PSI and dive time, and set a max depth for a dive plan.


I guess with the right planning and understanding it's not a bad idea at all. Just a lot of excess air to be carrying for the doubles buddy.

 

[vinegarbiscuit]

I agree with previous posters that out-of-air drills are a really good idea. Breathing off a long hose isn't rocket science, but it's important to get a feel for these things. Simulating an OOA drill at the start of each dive is a useful exercise. That way, you and your buddy can also ensure he hasn't mistakenly tucked his long hose into or around a piece of gear that could interfere with an air-share.

Not touching your buddy's isolator valve unless specifically asked to do so is extremely important, as DevonDiver said. A doubles diver should be proficient enough with performing valve drills, so that even if some loony on the boat or whatever turns it one way (thinking he/she's being helpful...it DOES happen), the doubles diver can easily deal with it underwater, usually while simultaneously questioning the parentage and personal hygiene habits of whoever messed with their gear through their regulator. You don't want to be the cause of all those expletives, do you?!

I would also recommend performing a bubble check for each other, so you can ascertain there are no leaks before the dive. If anything develops during the dive, you can indeed make a bubble motion to your buddy, and identify the source for him. That way, he can take whatever action's required, such as shutting off a leaking tank, without any ado, and set sail for home.