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Skipbreather · 10th October 2006, 22:02

Quote: (Originally Posted by jaap)

But I'm cuirous, does a std BCD type connector have enough flow for breathing? I guess DR figured it has?

I remember discussions about it and that a CEJN-fitting is better because of its better maxflow. And all those Air2, AutoAir and similar devices. They all use other connectors than std BCD. Must be for a reason?

Quote: (Originally Posted by Jordan)

At 20 feet and up, it does. It is not nearly as much flow as you are used to, but it is enough. You need to consciously breathe a little slower and longer, but it works just fine. Another thing, I wouldn't call this a std BCD type connector, as the holes on the end are bigger.

I’d view these as for EMERGENCY extension of deco use only.

Several years ago I was merrily machining my own manifolds for QD connection of both bailout 2nd stage and wing inflation from off board 1st stage. Originally used a standard BC inflator hose to a BC QD male connector on manifold. Wings worked fine but 2nd stage was like breathing thru a soda straw. If a diver was going OC as a bailout in anger, IMHO any BC type connector would not provide sufficient flow. If one were in a relaxed situation, say trying to access a little extra O2 to extend deco, perhaps but even then highly marginal. I went to one of the bigger bore connectors mentioned and all worked well.

There are 2 major restrictions to the flow. The one you see at the end of the male connector is one. The other is a Schrader valve hidden inside the connector end of the BC hose that is dimensionally identical to the one in your tires on your car/ bike/ whatever. Look at one of those up close & personal and you’ll see why the flow is so low.

Just my $0.02.

Ken

10th October 2006, 22:02	#9 (permalink)
Skipbreather Reads the fine print Current Rebreather/s: Megalodon Home Build Other Rebreather/s: Not Bought Yet MK 15.X Home Build Join Date: Mar 2005 Location: Chicago, Illinois, USA Posts: 555	Re: new product from DR Quote: (Originally Posted by jaap) But I'm cuirous, does a std BCD type connector have enough flow for breathing? I guess DR figured it has? I remember discussions about it and that a CEJN-fitting is better because of its better maxflow. And all those Air2, AutoAir and similar devices. They all use other connectors than std BCD. Must be for a reason? Quote: (Originally Posted by Jordan) At 20 feet and up, it does. It is not nearly as much flow as you are used to, but it is enough. You need to consciously breathe a little slower and longer, but it works just fine. Another thing, I wouldn't call this a std BCD type connector, as the holes on the end are bigger. I’d view these as for EMERGENCY extension of deco use only. Several years ago I was merrily machining my own manifolds for QD connection of both bailout 2nd stage and wing inflation from off board 1st stage. Originally used a standard BC inflator hose to a BC QD male connector on manifold. Wings worked fine but 2nd stage was like breathing thru a soda straw. If a diver was going OC as a bailout in anger, IMHO any BC type connector would not provide sufficient flow. If one were in a relaxed situation, say trying to access a little extra O2 to extend deco, perhaps but even then highly marginal. I went to one of the bigger bore connectors mentioned and all worked well. There are 2 major restrictions to the flow. The one you see at the end of the male connector is one. The other is a Schrader valve hidden inside the connector end of the BC hose that is dimensionally identical to the one in your tires on your car/ bike/ whatever. Look at one of those up close & personal and you’ll see why the flow is so low. Just my $0.02. Ken
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