Well, shit. I really didn't want to litter this thread with this so I'm done after this. Again appologies, hope someone gets something helpfull out of this.
To clear up any missunderstandings, the pressurized air device that is essensially a miniature scuba tank is called Rapid Air, the tube with a valve on the end is called Quick Air.
I gave Jeff of Rapid Products some engineering advice and drawings on the mouthpiece valve, specifically the exhaust part of the double check valve. I did this for purely altruistic reasons, the same reason I posted the previous replies on this thread. If I charged for it, it may have costed more, and that might have prevented a sale of a product I thought could save a life. I only mentioned my affiliation with the product to show credibility, that I wasn't just some yahoo.
In Ryan's situation, as I interpret it, I would actually prefer someone to have handed me a Quick Air rather than a tube. With a rescuer handing the device to victim, and maintaining control of the open end, the Quick Air is superior to a simple tube.
My concern with the Quick Air, and if you read my posts it should be evident, is that you are unable to purge the thing. If I'm pulling a Quick Air out of a pinned and swamped boat, blindly lifting it out of the water, popping the lid, and taking a quick breath, I think there is a good possibility that you could get a mouthful of water due to spray, slash, or popping the cap off too soon. It is unlikely that the water will be calm at the scene of a pin. If I've got a lung full of air, and I exchange that for a tube full of water, now I'm choking and that much closer to unconsiousness. This scenario is where I see the product "causing more harm than without."
So it is my OPINION that not knowing how the pin is going to occur or who is in control of the breating tube (rescuer or victim), the simple tube is the better choice if I was going to carry just one.
Jones, you are right on with your interpretation.
Gary E, I guess my response to you is the same, "what the hell are you talking about?" Your posts seem to be talking about both the Rapid Air and the Quick Air at the same time, therefore making no real sense. If you meant Rapid Air in your first reply, we agree, you just missunderstood and should probably read a little closer (or write a little more legibly). But to say I shouldn't come onto this forum with my comments where people share ideas is contradictory. I'm simply advising this community of a possible danger. And to answer your question, no, I've only used the Quick and Rapid Air on land, not submerged. But getting all aggro at me is just a bit uncalled for. Please try to contain yourself. If you still dissagree, fine, at least you are aware now of the purging issue.