Gas consumptionRMV and SAC
Respiratory Minute Volume and Surface Air Consumption from a dive.
Enter your tank size, average depth, dive time and the gas you used, and Deep Tools works out your breathing rate at the surface. It is the number you plan gas with.
How it works
SAC = used ÷ time ÷ (depth ÷ 10 + 1) · RMV = SAC × tank
- SAC surface air consumption in bar per minute
- RMV respiratory minute volume in litres per minute
Example
- Dive
- 12 L tank, 10 m, 55 min, 60 bar used
- SAC
- 60 ÷ 55 ÷ 2 = 0.5 bar / min
- RMV
- 0.545 × 12 = 7 L / min
How it works
SAC = used ÷ time ÷ (depth ÷ 32.8 + 1) · RMV = SAC × tank ÷ 3442 psi
- SAC surface air consumption in psi per minute
- RMV respiratory minute volume in cubic feet per minute
- Tank capacity in cubic feet at the 3442 psi service pressure
Example
- Dive
- 100 cf tank, 64 ft, 55 min, 1987 psi used
- SAC
- 1987 ÷ 55 ÷ 2.95 = 12.2 psi / min
- RMV
- 12.24 × 100 ÷ 3442 = 0.356 cf / min
Take it to the dive site
The same calculator works offline in the Deep Tools app, together with the dive planner, dive log and blender.
