96 NAUI Nitrox Diver
Appendix D
Absolute Pressure at Depth
Depth
(msw)
Depth
(fsw)
Pressure
(ata)
0 0 1
3 10 1.3
6 20 1.6
9 30 1.9
12 40 2.2
15 50 2.5
18 60 2.8
21 70 3.1
24 80 3.4
27 90 3.7
30 100 4.0
34 110 4.4
37 120 4.7
40 130 5.0
43 140 5.3
46 150 5.6
Figure D-8 This table can be used to convert either from depth to
absolute pressure or absolute pressure to equivalent depth.
Oxygen Partial Pressure (in atmospheres absolute) at Depth
FO2 Air 0.24 0.26 0.28 0.30 0.32 0.34 0.36 0.38 0.40
Figure D-9 Oxygen partial pressure at depth for various nitrox blends–moderate shading indicates an oxygen
partial pressure between 1.4 and 1.6 ata. Dark shading indicates oxygen partial pressure in excess
of 1.6 ata.
Depth
(msw)
Depth
(fsw)
12 40 0.46 0.53 0.58 0.62 0.66 0.71 0.75 0.80 0.84 0.88
15 50 0.53 0.60 0.65 0.70 0.75 0.80 0.86 0.91 0.96 1.01
18 60 0.59 0.68 0.73 0.79 0.85 0.90 0.96 1.01 1.07 1.13
21 70 0.66 0.75 0.81 0.87 0.94 1.00 1.06 1.12 1.19 1.25
24 80 0.72 0.82 0.89 0.96 1.03 1.10 1.16 1.23 1.30 1.37
27 90 0.78 0.89 0.97 1.04 1.12 1.19 1.27 1.34 1.42 1.49
30 100 0.85 0.97 1.05 1.13 1.21 1.29 1.37 1.45 1.53 1.61
33 110 0.91 1.04 1.13 1.21 1.30 1.39 1.47 1.56 1.64 1.73
36 120 0.97 1.11 1.21 1.30 1.39 1.48 1.58 1.66 1.76 1.85
40 130 1.04 1.19 1.28 1.38 1.48 1.58 1.68 1.77 1.88 1.98