Second Dive: Post-Dive Profile
After the second dive, the following details are known.
- TOD: 15 m/49 ft.
- Actual depth: 15 m/49 ft.
- NDL: 33 min.
- Actual time: 30 min.
- Cylinder: 90 bar/1,323 psi (gas pressure on surface)
Calculating SAC
SAC is calculated by using the following information.
- Gas used: 110 bar/1,677 psi or 1,221 L/44.72 cu. ft.
200 bar - 90 bar = 110 bar
3,000 psi - 1,323 psi = 1,677 psi
or
110 bar × 11.1 L = 1,221 L
80 cu. ft. × 1,323 ÷ 3,000 = 35.28 cu. ft.
80 cu. ft. - 35.28 cu. ft. = 44.72 cu. ft. - Time: 35 minutes
30 min. (Dive Time) + 2 min. (Ascent Time) + 3 min. (Safety Stop Time) = 35 min.
- Average depth: 12 m/39 ft./2.2 bar
Metric
1,221 L ÷ 35 min. = 34.88 L p/m (RMV)
34.88 L ÷ 2.2 bar = 15.85 L p/m (~16 L p/m) (SAC)
Imperial
44.72 cu. ft. ÷ 35 min. = 1.28 cu. ft. p/m (RMV)
1.28 cu. ft. p/m ÷ 2.2 bar = 0.58 cu. ft. p/m (SAC)