Hello all,
I am now the proud owner of a yellow box and am looking at doing the course within the next few months. I won't be using the unit until I have full training but have a few basic questions that I was hoping that someone could help with.
I understand the rebreather concept, how it works etc but I have a bit of a query:
When I breathe in from the counterlung, I breathe whatever the PP setpoint is (basically) but when I breathe out I have used about 4% of the O2 and expell CO2 from my body. The CO2 is removed from my expelled air by the scrubber. It's then analysed and the reduced O2% is then topped up from the O2 cylinder. My question is, does this mean that the counter lung volume slowly increases or does the scrubber absorb the correct volume of CO2 expelled by my body?
I hope that makes sense what I'm trying to ask? Obviously if the counter lung volume increases at times the ecess is going to have to be purged.
My second question (sorry guys) is more to do with no-stop times. Because I'm going to be breathing from a closed loop, does my body absorb the same amount of Nitrogen as if I was on Open Circuit? I mean if I have a set-point of 1.5 Bar on CC and compare it to an Open Circuit of 30% at 40M (PPO2 = 1.5Bar) is the no-stop time the same, or because it's closed loop is the no-stop time longer?
I hope that these questions aren't stupid ones and I thank you all in advance.
John
