Gas planning
Estimate time to reserve before the plan gets optimistic
Estimate usable gas and time to reserve from SAC, tank size, start pressure, reserve pressure, and average depth.
Planning aid
Tank, SAC, and reserve
Estimate minutes available before a reserve pressure, not including a reserve as planned usable gas.
L/min
L
bar
bar
m
Usable gas to reserve
1800 L
Time to reserve
36 min
Reserve at this depth
12 min
Planning boundary: Gas estimates are simplified planning aids. They do not calculate rock-bottom gas, buddy gas sharing, ascent requirements, workload spikes, current, stress, regulator performance, or emergencies.
Formula and source notes
For gas planning context, review DAN gas management discussion and confirm reserve rules with the operator or instructor.