O2 Reg (and tank) technical question

[TheAvatar]

I really didn't know where else to ask this. I am hoping some of the technical types here would know the answer.

When an O2 (or air) cylinder is given a volume rating ex: D cylinder is said to have 350L @ 2000psi or AL80 to have 80CF @ 3000psi, that means it contains enough gas to fill a volume of that number if it were expanded until it reached ambient presssure. I assume that all of those values based on STP (20C 1Atm). Is that correct?

If the flow rate dial on a portable O2 reg is set to a given value (say 15LPM), is the actual flow volume rate affected by temperature or ambient pressure or does the regulator compensate for that? Will it release 15LPM at 0C 0.8Atm and at 20C 1Atm? Or will it release more or volume per minute for given environmental conditions.

 

[rescuediver009]

When an O2 (or air) cylinder is given a volume rating ex: D cylinder is said to have 350L @ 2000psi or AL80 to have 80CF @ 3000psi, that means it contains enough gas to fill a volume of that number if it were expanded until it reached ambient presssure. I assume that all of those values based on STP (20C 1Atm). Is that correct?

If the flow rate dial on a portable O2 reg is set to a given value (say 15LPM), is the actual flow volume rate affected by temperature or ambient pressure or does the regulator compensate for that? Will it release 15LPM at 0C 0.8Atm and at 20C 1Atm? Or will it release more or volume per minute for given environmental conditions.

Yes, the cylinder capacity if released will fill a box the rated size at standard temp and pressure.

The flow rate is not affected by temperature and pressure. The oxygen in the bottle is pressurized and will not change its pressure unless there is a significant temperature increase (left in a car on a hot day). It this case however, there is just more pressure in the tank. It s still however regulated to come out into the non-rebreather, or BVM at the rate specified by the dial.
I think that you are thinking if the bottle were flexible, like a bag and you were under water say 3 ATM then the bag would be crucshed somewhat by the pressure of the water somewhat incresing the pressure of the bag of air. The regulator would still however 'regulate' the pressure and thus the flow rate coming out.