Some Thoughts on Independent Doubles

[Marie13]

For me, an immediate advantage was/is not having to reconfigure the regs I used for my manifolded BM doubles--except for adding a SPG. I already owned the manifolded doubles and hardware, etc., so all I needed to do was remove the isolator part.

Another advantage is, rec diving BM doubles (either manifolded or independent) keeps your front torso clear of clutter.

rx7diver

Your torso doesn’t get cluttered if you don’t sling your pony across your body. It looks absolutely ridiculous.

 

[Raphus]

I dont really get the advantage of ID BM.
I dive manifolds open. If something happens i can just close them.

The possibility is much higher, that a first stage fails, which doesnt require ID. So i can just close the valve and dive with both tanks.
I see more disadvantages then advantages.
And i rarely see ID ( besides sidemount ofc).
Pony bottles are a rare sight here, seems more like a american thing.

Most advanced diver here usually use manifolded doubles. So i might be a bit biased. But i still dont get, why i should dive ID or with the manifold closed. The manifold is there, to do a valve drill and close it when needed.

 

[MichaelMc]

The manifold is there, to do a valve drill and close it when needed

For some the notion of rapidly closing a manifold is just not a reality.

Swapping regs, sure. (side or ID)
Maybe managing to crack open the manifold to re-equalize, sure. (progressive)
Rapidly closing it, no.

So there are other ways.

 

[Marie13]

For some the notion of rapidly closing a manifold is just not a reality.

You mean because they physically can’t do it?

 

[MichaelMc]

You mean because they physically can’t do it?

Yes. Or they could with diligent and persistent conditioning and stretching but that is not as much a part of their life.

And the goal is presumably not dive with both tanks, but to have plenty of air to surface now that they had a malfunction. The case of needing air to fight a current back up is certainly there, but the manifolded ID option handles that.

 

[Marie13]

Yes.

Side mount, then.

 

[rjack321]

For some the notion of rapidly closing a manifold is just not a reality.

Swapping regs, sure. (side or ID)
Maybe managing to crack open the manifold to re-equalize, sure. (progressive)
Rapidly closing it, no.

So there are other ways.

The number of people dying from closing a cross bar manifold too slowly is somewhere around zero.

The number of people screwing up their gas management (either SM or BM) is legion and absolutely has killed people. For instance the 2 videographers in Grand Cenote Paso de Lagarto line about 3 years ago.

 

[MichaelMc]

The number of people dying from closing a cross bar manifold too slowly is somewhere around zero.

There are people who can not reach a manifold. Should they not have a redundant option?

ETA: I'm not talking about caving here. Just open water diving with one type of gas.

 

[AfterDark]

Side mount, then.

Tried it, don't like, not interested I'll stick with my BM IDs they've always worked just fine for me. Maybe for others but for me , why switch now in my twilight years?

 

[Marie13]

Tried it, don't like, not interested I'll stick with my BM IDs they've always worked just fine for me. Maybe for others but for me , why switch now in my twilight years?

If you didn’t want two tanks on your back, maybe.