5
Chapter 5 Dive Tables and Dive Computers 63
Since, the nitrogen fraction is “one minus the
oxygen fraction,” you can add even another twist into
the formula by substituting (1 - FO2) for FN2, and the
formula becomes:
or in the U.S. formula
Using the NAUI MobileTM App to
Determine Equivalent Air Depth (EAD)
The NAUI MobileTM Application EAD Tool allows divers
to calculate EAD similar to how MOD and Best Mixes
are calculated. The EAD calculator can calculate nitrox
mixes from 21% to 40% O2 and planned depths of up
to 40 meters (130 feet). From the NAUI MobileTM App,
open the Dive Tools menu. Use the slide-bars to select
the appropriate FO2 and planned depth. For example, the
EAD for a FO2 of .40 (or 40% O2) with a planned depth
of 24 meters (79 feet) is just 16 meters (52 feet) (Figure
5-6).
USING THE NAUI RGBM NITROX
DIVE TABLES
NAUI RGBM Dive Tables are “no-calculation” tables
and do not require use of letter groups, a surface
interval credit table, or residual nitrogen times, thus
making repetitive dive planning extremely easy and
straightforward.
NAUI RGBM Dive Tables have been prepared for
EAN32 (Figure 5-7) and EAN36 (Figure 5-8) as well as
for air diving. The sea-level tables provide dive-planning
information for altitudes up to 610 meters (2000 feet).
Additional sets of tables are available for diving at
altitudes between 610 and 1829 meters(2000 and 6000
feet) and for 1829 to 3048 meters (6000 to 10,000 feet).
Figure 5-6 The NAUI MobileTM App dive tool
calculators simplify finding equivalent air
depth during dive planning.
Reduced Gradient Bubble Model (RGBM)
Dive Table - EAN 32
Sea Level to 2,000 ft / 610 m
DIVE ONE
DIVE TWO
DIVE THREE
MDT MDT MDT
MAX DEPTHS
MAX DEPTHS
MAX DEPTHS
fsw
120
110
100
90
80
70
60
50
40
msw
36
33
30
27
24
21
18
15
12
minutes
20
25
30
38
47
60
85
115
150
fsw
80
75
70
65
60
55
50
45
40
msw
24
23
21
20
18
17
15
14
12
minutes
47
47
60
60
85
85
115
115
150
fsw
40
40
40
40
40
40
40
40
40
msw
12
12
12
12
12
12
12
12
12
minutes
150
150
150
150
150
150
150
150
150
This table is designed for scuba dives employing EAN 32.
Read the instructions on the back and seek proper training before
using this table or EAN 32. Even strict compliance with this table will
not guarantee avoidance of decompression sickness.
Copyright © 2019 NAUI Worldwide. All rights reserved. #35514
Figure 5-7 NAUI RGBM Sea Level Nitrox Dive Table -
EAN32
Reduced Gradient Bubble Model (RGBM)
Dive Table - EAN 36
Sea Level to 2,000 ft / 610 m
DIVE ONE
DIVE TWO
DIVE THREE
MDT MDT MDT
MAX DEPTHS
MAX DEPTHS
MAX DEPTHS
Read the instructions on the back and seek proper training before using
this table or EAN 36. Even strict compliance with this table will not
guarantee avoidance of decompression sickness.
Copyright © 2019 NAUI Worldwide. All rights reserved. #35517
fsw
110
100
90
80
70
60
50
msw
33
30
27
24
21
18
15
minutes
31
35
46
60
85
115
150
fsw
80
75
70
65
60
55
50
msw
23
21
20
18
17
15
14
minutes
60
60
85
85
115
115
150
fsw
50
50
50
50
50
50
50
msw
15
15
15
15
15
15
15
minutes
150
150
150
150
150
150
150
This table is designed for scuba dives employing EAN 36.
Figure 5-8 NAUI RGBM Sea Level Nitrox Dive Table -
EAN36
(D msw + 10 msw) × (1 − FO2 )
EAD msw =( 0.79
) − 10 msw (D fsw + 33 fsw) × ( 1 − FO2 )
EAD fsw = ( 0.79
) − 33 fsw