Diving with Twins

[MA.25]

Does diving with twin tanks require training,

what do I have to do/get to use them.







:sblogo:

 

[SDAnderson]

Although training isn't required you'll find the process is a whole lot easier if you have someone in the water with you who knows what they're doing and can provide input to assist with the transition. They're going to goof up your buoyancy (a lot) and trim (even more) and move your center of gravity far enough to make you swim like a drunken turtle.

The first time you end up on your back on the bottom you'll wish you didn't have somebody watching, however...

 

[ajduplessis]

Yes, training is required. Tech diving should be a good place to start. Prerequisites normally are: Advanced Nitrox, min 100 dives of which 30 must exceed 90 feet. Standards differ between agencies, please keep this in mind.

 

[NJDiver07866]

Everyone will have an opinion, but I say go for it. You must understand how to use the manifold or if no manifold learn to do some gas switches to keep the redundancy. This in itself everyone has their own opinion on what is better.

DIR guys have an exact science on how this should be done. You should read up on the DIR way GUE i think it's called? They have some good info on the topic.

Worst case hook up with someone that can help.

Sorry for asking, but why are you going doubles? Just take care. With doubles another issue is you are carrying more of that pesky nitrogen on your back. With singles not to say there is less risk, but you can't load yourself up as much before running out of gas. With doubles you can take a nap and load up your tissues pretty good. Take it with a grain of salt though... this is along the lines with gas matching. I see people with double 120 cubic feet that end the dive with 4/5 of the gas left.....

Take care and dive safe

 

[ajduplessis]

I cannot believe an instructor encourage any form of diving without training.

 

[bamamedic]

I cannot believe an instructor encourage any form of diving without training.

While it's important to seek training for most things...the vast majority of divers I know seem to learn how to dive doubles through mentorship from more experienced divers. There's nothing too terribly hard about them, as long as you are willing to do the legwork, read up on it, obtain mentorship from experienced doubles divers, and don't dive beyond your limitations (i.e. don't get yourself into a situation that you can't get out of yourself).

I'd be more concerned as to why the OP, at the minimal dive experience listed on his profile, is interested in diving doubles...

MILGENTOSH, generally, people learn to dive doubles as a prerequisite for more advanced training, such as cave or decompression training, and at 0-24 dives, you'd get a lot more out of concentrating on getting your basic diving skills down pat, not taking on something like this.

MILGENTOSH, you didn't list a reason for wanting to get into doubles, but most newish divers usually want to because they feel that their air usage is so high that doubles are the only way to get a decent amount of bottom time. Most new divers will have a high air usage rate, anyways, and you'll be surprised at how much longer your air will last when you have just a few more dives under your belt. Try to concentrate on slowing down underwater (many divers rush and try to see everything at once). When you slow down, your air usage decreases to the point where you'll actually see more stuff than if you rushed around. Relax, take slow and steady breaths, and as you become more comfortable in your underwater enviroment, you'll discover that you air will last much longer!

Double cylinders are a great tool for certain dives, but they do add a significant additional expense, since you'll need about $300 US worth of equipment just to connect the two cylinders together, and you'll need to purchase an additional regulator. They also add an element of complexity, 'cause now you have to worry about things going wrong with both cylinders and regulators, and if you're not paying attention, you can overstay your welcome and rack up enough bottom time to go into mandatory deco, which adds a ton of extra risk and other issues.

 

[Wookie]

I cannot believe an instructor encourage any form of diving without training.

I can't believe that anyone would require formal training for most equipment type new forms of diving.

I look at it this way. If I am trying out new equipment, ex. pony, twinset, DPV, drysuit, and the manufacturer will let me buy it without a card, I'm going to head to the pool, then the lake/beach with it and practice, and see how screwed up I can get with it in controlled or semicontrolled environments. If I can find a mentor, all the better. I'm not headed for the ocean until I have developed mastery (at least in my mind).

If I'm trying out new techniques or philosophies to diving, and it is generally accepted that you can't do that type of diving with a dive operator without formal training, (cave, trimix, solo), by all means, go find an instructor.

Sometimes you have new gear and new philosophies (rebreather). In that case, hours of practice are part of the formal training required for card issuance.

One training agency has made their living issuing BS cert cards to unsuspecting divers, poisoning a whole generation of instructors. That gives us instructors who feel that you can't get in the water with a speargun without a "underwater Hunter" diving specialty, or you can't use a point and shoot without a "Underwater Photographer" certification card. I gotta tell you, when someone shows me their "Boat Diver" certification card, I don't feel a shiver down through my toes. Other training agencies have followed suit, seeing the cash cow that card issuance has become.

I understand why you think that formal instruction is needed to dive a twinset. Diving in the past 20 years has evolved into the feeling that anyone can dive if you instruct them enough. The fact of the matter is, not everyone can dive, some will never get it no matter how much instruction you give them. The longer you teach and are exposed to more other instructors and more diving philosophies, the more you will realize that only about 10% of instructors out there can really teach (I'm one of the 90%, so I don't teach).

 

[Akimbo]

It depends on your reasons for wearing doubles, conditions, and abilities. Say you are a photographer in warm water and want more time above 40'. You can probably figure it out just fine. On the other hand, if the objective is to dive deeper wrecks in the North Atlantic it may be a good idea. If all you need is more exercise and want to get back on the boat with 1800 PSI in reserve, go for twin 120s. If you don't have a good reason, stick with singles and spend on stuff that is more fun.

Will doubles be the only change or will you need new buoyancy compensation gear, harness, additional regulator, a dry suit, decompression stage bottles, and maybe a computer? Will using doubles result in exposure to decompression dives that would be new to you? After answering these questions, you will have the answer to your question.

 

[DanRite]

Does diving with twin tanks require training,

what do I have to do/get to use them.







:sblogo:

I would suggest you take a techinical course or Cavern/Intro Cave course that some instructors teach in doubles. Some agencies will teach these courses in single mount with an H or Y valve, so ask before signing up. They will go over the gear with you and talk about trim, buoyancy and safety. You will also learn about accident analysis and redundency, and most importantly, you will have drills that go over valve and islolator failures, buddy sharing, etc...

 

[super7]

Does diving with twin tanks require training,

what do I have to do/get to use them.

:sblogo:

Wow.
Everyone's talking about whether training is necessary or not.
It seems MILGENTOSH wants to know what he might need as well.

1) two sets of regs and a set of hoses to go with them.
2) a BC that can accommodate double tanks.
I'll bet most will recommend a BP/W set up. There are soft back plates on the market, but with the weight of two tanks, two regulators and other hardware being fixed to the plate, a hard backplate should be more stable and easier to manage.

These are the bare minimum of what you will need to get before you can get the doubles on your back.You'll need other accessories like regulator necklaces and bolt snaps, but I'll leave these to the dive shop attendant you'll be talking to when you buy your gear.

BTW, incase you're diving split fins, this might be the time to switch over to old school fins.

Kaza