SMB with dump valve?

[Humuhumunukunukuapua'a]

I got a safety sausage for Christmas, and it looks pretty nice. One feature confuses me, though.

It is open at the bottom, so I guess you can fill it with your backup reg. Then a few inches above the bottom, there's a dump valve. My brother got a different sausage with the same setup.

So, what is that dump valve for? I feel like I must be missing something obvious. But any expanding air would be released out the bottom of the sausage, so what gives?

Here's the sausage in question:
http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=LargeSafety

Gregg

 

[GreenDiverDown]

So, what is that dump valve for? I feel like I must be missing something obvious. But any expanding air would be released out the bottom of the sausage, so what gives?

Blow some air into the bottom of your bag... 3 or 4 breaths... then role down from the top to push the air to the bottom. Does it come out? Probably not. If it is a semi-closed design the air inlet is baffled so that air can't come back out. The OPV valve is required to prevent a rupture.

 

[Humuhumunukunukuapua'a]

Hey you're right. It looks like it's just open at the bottom, but there is some sort of valve system a little ways up the sausage. Thanks. I was just being dumb

 

[ScottZeagle]

That is to keep air from escaping. You can use it as a small lift bag, if you desire, and shoot it up from the bottom, or you can deploy it during your safety stop to let the boat know where you are.

The over pressure valve is to allow air to escape as it expands - otherwise it would just pop.

That type of inlet valve, however, works much better when it is wet, so don't be suprised if it loses air over a period of time out of the water...

Scott