I read about every thread I could find on these terms (well. except for LMNO...) and the first two seem to be used interchangably. Examples:
I found SCR expressed as PSI per minute and cylinder dependent, as well as expressed as a volume measurement.
I found SAC expressed as Cu Ft per minute and not cylinder dependent...
RMV...what the heck is this?
In my SSI AOV, I received the dive planning slate and assorted hoopla that goes along with it (EAD/MOD Calc, Tables, etc.) and there is this device with dials, windows and pointers used to calculate SCR, and its expressed in "P.S.I. / MIN" Several threads I read express SCR in volume, not pressure. I've been using the device to track the SCR of my dives.
As you know, I am attempting to reduce my absolute computer dependance (my OMS SPG will be in tomorrow...) and regenerate some of my rotted brain.
With 60+ meticulously logged dives, I want to establish a baseline of gas comsumption so I can better plan my dives. I think diving in ignorance and racing to the chain with XXX gas is just lame, as I always emerge with way too much. Not that I want to plan so I surface with my last breath, but theres a lot to see, and I'm missing it because I keep emerging with 1200, 1300, 1000, etc. I understand some of this is buddy dependent, etc. But you see me working. My plan should be based on my consumption, not on a clock on my computer. Baseball, not football.
I've been using the SSI device, and I've seen a dramatic improvement/reduction in my SCR. Since I've been using the same cylinder for almost all of my dives, I can only conclude that as I've been diving more, I'm diving smarter and using less gas.
That said, I need to know more about this alphabet soup.
Is there a generally accepted preference - volume or pressure? How is that correctly expressed (SCR, SAC...which is which?) Is there a preference for reaching my objectives? Are my objectives realistic? I can't imagine not knowing my consumption. It just seems ignorant and unsafe not to know, you know?
Can my objective (baseline gas consumption under various conditions) be achieved using one of these two formulas?
As there is nobody in my diving circle that would aspire to something so bold as to one day pocket their computer, I'm pretty much without mentor or guide in this endeavor. Any assistance would be appreciated as I plow through this alone. Use small words.
Its late - my brain hurt.
Thanks -
Ken