Beep beep going into decom :-( or :-)

[Poulpe]

Sorry I will change a little the units.

You said that you have 1000 psi in your tank when you start ascent.
1000 psi = 70 bars
let's say that you want to go to the surface with a minimum of 435 psi (30 bars). In a 15 liter tank, the rest is :
40 bars x 15 l = 600 Liters of gaz (air)

Consider that your consommation of gaz is 25 L/min at the surface, that's 38.5 L/min at 15 feets. So you have about 600 L / 38.5 = 16 minutes of deco time minimum (and you will still get 435 psi in your tank)

I don't think a deco stop time of 3 minutes is long. I regularly have longer deco stops.

 

[Genesis]

Consider that your consommation of gaz is 25 L/min at the surface, that's 38.5 L/min at 15 feets. So you have about 600 L / 38.5 = 16 minutes of deco time minimum (and you will still get 435 psi in your tank)

What happens if you have a freeflow just as you begin the deco?

If you're going to do intentional decompression dives you need to KNOW you have the gas supply to complete the mandatory deco time.

 

[scubatexastony]

Peo once bubbled...




But the difference here is the situation you are in once that emergency that caused you to shut down has been dealt with. When you shut down one of your first stages you have lost half your remaining gas supply (given "proper" gas management). With a manifold, you have the same amount of gas available, for both you and your buddy.
Anyways, better not turn this into a manifold or no manifold war -- I just want to point out that it's not a 100% accurate description that diving independent doubles utilizes a simpler technical system, and therefore is safer.

So if I have a manifold, isolated I presume your are talking about, and I loose a reg and have to isolate that side....how is it that "I still have the same amount of gas available"? Not only did I lose some gas from the isolated tank, I lost whatever amount from the remaining tank prior to shut down.....

tony