ATJ
Contributor
Also note that SAC in Subsurface is RMV in a lot of other software.Usual "warning" when looking at Subsurface SAC rates. We actually try to approximate compressibility of gases, so our SAC rates may be different (usually slightly lower) from those calculated using naive math assuming perfect compressibility of gases. Because no, your cylinder doesn't contain twice as much gas when you go from 150bar to 300bar.
In Garmin Connect, metric SAC is bar/min and doesn't take tank size into consideration.