2
34 NAUI Nitrox Diver
depth (EAD), maximum operating depth (MOD), or best
nitrox mix (Figure 2-10). Divers may also reference the
NAUI Air, EAN32, and EAN36 Dive Tables or the NAUI
RGBM tables.
Verify What You Have Learned
Review the following questions about
Gases and Gas Mixtures:
1. Each of the individual components in a gas
mixture will exert its chemical or physical effects
independently, according to what?
2. Oxygen is what percentage of atmospheric air?
Nitrogen?
3. The symptoms of nitrogen narcosis parallel those
often seen in what?
4. If we heat a gas, we are adding _____, increasing
the speed of the molecules and the force of the
impacts.
5. Which law states: "At a constant temperature, the
volume of a gas varies inversely with absolute
pressure, while the density of a gas varies inversely
with absolute pressure."?
6. Which law states: "The amount of any given gas that
will dissolve in a liquid at a given temperature is a
function of the partial pressure of the gas that is in
contact with the liquid and the solubility coefficient of
the gas in the particular liquid."?
7. What is the portion of the total gas pressure exerted
by a single gas in a mixture of gases?
8. Which law states: "The total pressure exerted by a
mixture of gases is equal to the sum of the pressures
that would be exerted by each of the gases if it
alone were present and occupied volume."?
9. Each _____ that you descend in the ocean adds
another atmosphere of pressure to the one
atmosphere of surface pressure.
10. When you are at a depth of 20 meters of seawater
(msw)/66 feet of seawater (fsw), the absolute
pressure is what?
11. To convert depth to absolute pressure, you first find
the water (hydrostatic) pressure in atmospheres and
then add what?
12. To determine the partial pressure of a gas in a
mixture, you multiply what two numbers?
13. Using the Oxygen Partial Pressure at Depth table,
what is the PO2 of EAN34 at a depth of 24 msw
(80 fsw)?
For answers, see Appendix.
WARNING: EVEN STRICT COMPLIANCE WITH
THESE TABLES WILL NOT GUARANTEE AVOIDANCE
OF DECOMPRESSION SICKNESS. CONSERVATIVE
USAGE IS STRONGLY RECOMMENDED.
RNT
+ADT
TNT
(USE THIS FIGURE TO DETERMINE
END-OF-DIVE LETTER GROUP.)
0.6
9
30
DIVE TIME REQUIRING DECOMPRESSION
MINUTES REQUIRED AT 15-FSW STOP (5-MSW) 00 00
35
1
30
4
A B C D E F G H I J K L M N O
0.8
15
50
TABLE 3 - REPETITIVE DIVE TIMETABLE
RNT
+ADT
TNT
(USE THIS FIGURE TO DETERMINE
END-OF-DIVE LETTER GROUP.)
SHADE INDICATES PO2 GREATER THAN
1.4 ATM OR O2 TIME LIMIT EXCEEDED
DIVE TIME REQUIRING DECOMPRESSION
MINUTES REQUIRED AT 15-FSW STOP (5-MSW) 00 00
0.9
15
50
2
1
0
Figure 2-10 Many tables are available to simplify
nitrox dive planning.
21
779
34
766
48
752
63
737
79
721
98
702
118
682
141
659
167
633
198
602
237
563
286
514
354
446
465
0
0.7
12
40
18
282
28
272
39
261
51
249
63
237
77
223
92
208
108
192
126
174
146
154
168
132
194
106
224
76
260
0
SHADE INDICATES PO2 GREATER THAN
1.4 ATM OR O2 TIME LIMIT EXCEEDED
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
60
33
27
20
15
12
10
9
7
6
6
6
88
47
30
27
21
17
14
12
11
9
9
8
121
62
50
36
28
22
19
16
14
12
12
11
163
78
62
44
34
28
23
20
17
15
15
14
217
97
76
53
41
33
28
24
21
18
18
15
297
117
91
63
48
39
32
28
24
21
20
449
140
107
73
56
45
37
30
25
25
*
166
125
84
63
50
40
198
145
95
71
236
167
108
75
285
193
121
6
9
12
15
18
21
24
27
30
33
36
40
20
30
40
50
60
70
80
90
100
110
120
130
80
2
55
2
30
4
45
2
135
6
24:00
10:02
10:01
8:45
8:44
7:51
7:50
6:59
6:58
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
9:10
9:09
7:53
7:52
6:59
6:58
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
8:17
8:16
7:01
7:00
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
12:38
12:37
11:22
11:21
10:28
10:27
9:35
9:34
8:43
8:42
7:51
7:50
6:59
6:58
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
11:46
11:45
10:30
10:29
9:35
9:34
8:43
8:42
7:51
7:50
6:59
6:58
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
10:54
10:53
9:38
9:37
8:43
8:42
7:51
7:50
6:59
6:58
6:07
6:06
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
7:25
7:24
6:09
6:08
5:14
5:13
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
6:33
6:32
5:17
5:16
4:22
4:21
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
5:41
5:40
4:24
4:23
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
4:49
4:48
3:32
3:31
2:38
2:37
1:45
1:44
0:53
0:52
0:10
24:00
3:56
3:55
2:40
2:39
1:45
1:44
0:53
0:52
0:10
24:00
3:04
3:03
1:48
1:47
0:53
0:52
0:10
24:00
2:12
2:11
0:56
0:55
0:10
24:00
1:17
1:16
0:10
24:00
0:10
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
PO2
msw
fsw
9
41
14
36
19
31
24
26
29
21
35
15
40
10
46
4
50
0
11
64
17
58
23
52
29
46
35
40
42
33
49
26
57
18
65
10
73
2
75
0
0.5
6
20
1.0
21
70
0.9
18
60
13
117
21
109
29
101
37
93
45
85
55
75
64
66
74
56
85
45
97
33
109
21
122
8
130
0
1.1
24
80
1.2
27
90
1.3
30
100
1.4
33
110
1.5
36
120
1.6
40
130
8
32
12
28
16
24
20
20
25
15
29
11
34
6
39
1
40
0
7
23
10
20
14
16
18
12
22
8
25
5
29
1
30
0
6
19
9
16
12
13
16
9
19
6
22
3
25
0
5
20
8
17
11
14
14
11
17
8
20
5
23
2
25
0
5
15
8
12
11
9
14
6
17
3
20
0
5
10
87
10
5
13
2
15
0
NEW
GROUP
TABLE 2 - SURFACE INTERVAL TIME TABLE
LIGHT FACE / BLACK NUMBERS (TOP) ARE RESIDUAL NITROGEN TIMES (RNT)
BOLD FACE / RED NUMBERS (BOTTOM) ARE ADJUSTED NO-STOP REPETITIVE
DIVE TIMES. ACTUAL DIVE TIME SHOULD NOT EXCEED THIS NUMBER.
00
00
RESIDUAL NITROGEN TIME
ACTUAL DIVE TIME
TOTAL NITROGEN TIME
EAN 32 DIVE TABLE
USE ONLY WITH 32% OXYGEN ENRICHED AIR
TABLE 1 - END-OF-DIVE LETTER GROUP
START
DEPTH
msw fsw
MAXIMUM
NO-STOP TIME
00
20
5
25
3
© 2019 NAUI WORLDWIDE
#35502-32 (Rev. 07/19)
PO2
TIME RANGES IN HOURS : MINUTES
ENTER FROM THE TOP, MOVE DOWN TO FIND SURFACE INTERVAL TIME.
MOVE LEFT TO FIND THE NEXT PRESSURE GROUP.
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
36
20
17
12
9
7
6
5
4
4
4
3
354
223
465
260
130
* HIGHEST ATTAINABLE GROUP AT THIS
DEPTH REGARDLESS OF BOTTOM TIME
** RESIDUAL NITROGEN TIME (RNT)
EXCEPTION (see rule on reverse)
500
5
300
5
EAN 36 DIVE TABLE
USE ONLY WITH 36% OXYGEN ENRICHED AIR
TABLE 1 - END-OF-DIVE LETTER GROUP
WARNING: EVEN STRICT COMPLIANCE WITH
THESE TABLES WILL NOT GUARANTEE AVOIDANCE
OF DECOMPRESSION SICKNESS. CONSERVATIVE
USAGE IS STRONGLY RECOMMENDED.
RESIDUAL NITROGEN TIME
ACTUAL DIVE TIME
TOTAL NITROGEN TIME
MAXIMUM
NO-STOP TIME
00
NEW
GROUP
TABLE 2 - SURFACE INTERVAL
LIGHT FACE / BLACK NUMBERS (TOP) ARE RESIDUAL NITROGEN TIMES (RNT)
BOLD FACE / RED NUMBERS (BOTTOM) ARE ADJUSTED NO-STOP REPETITIVE
DIVE TIMES. ACTUAL DIVE TIME SHOULD NOT EXCEED THIS NUMBER.
TIME RANGES IN HOURS : MINUTES
ENTER FROM THE TOP, MOVE DOWN TO FIND SURFACE INTERVAL TIME.
MOVE LEFT TO FIND THE NEXT PRESSURE GROUP.
TABLE 3 - REPETITIVE DIVE TIMETABLE
A B C D E F G H I J K L M N O
1.3
24
80
1.4
27
90
9
41
14
36
19
31
24
26
29
21
35
15
40
10
46
4
50
0
8
32
12
28
16
24
20
20
25
15
29
11
34
6
39
1
40
0
3:30
3:29
2:38
2:37
1:45
1:44
0:53
0:52
0:10
2:38
2:37
1:45
1:44
0:53
0:52
0:10
1:45
1:44
0:53
0:52
0:10
0:53
0:52
0:10
0:10
24:00
2:12
2:11
0:56
0:55
0:10
24:00
1:17
1:16
0:10
24:00
0:10
101
43
27
23
17
14
12
10
9
7
158
61
38
32
24
19
17
14
12
11
245
82
50
42
31
25
22
19
16
14
426
106
62
52
39
31
28
23
20
17
165
91
74
55
43
39
32
28
24
205
107
87
63
50
45
37
30
25
256
125
100
72
56
50
40
330
145
115
82
60
461
167
131
92
185
105
3
100
14
65
3
55
3
35
3
30
5
45
3
190
3
PO2
msw
fsw
15
170
24
161
33
152
43
142
53
132
64
121
75
110
88
97
101
184
116
69
132
53
149
36
169
16
185
0
1.0
18
60
12
88
18
82
25
75
32
68
40
60
48
52
56
44
64
36
73
27
83
17
93
7
100
0
10
50
15
45
20
40
26
34
32
28
38
22
44
16
51
9
58
2
60
0
7
23
10
20
14
16
18
12
22
8
25
5
29
1
30
0
6
19
9
16
12
13
16
9
19
6
22
3
25
0
1.5
30
100
1.6
33
110
1.2
21
70
0.6
06
20
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
START
DEPTH
PO2 msw fsw
00
00
0.7
09
30
0.8
12
40
18
282
28
272
39
261
51
249
63
237
77
223
92
208
108
192
126
174
146
154
168
132
194
106
224
76
261
39
300
0
0.6
0.7
0.8
0.9
1.0
1.2
1.3
1.4
1.5
1.6
6
9
12
15
18
21
24
27
30
33
20
30
40
50
60
70
80
90
100
110
* HIGHEST ATTAINABLE GROUP AT THIS
DEPTH REGARDLESS OF BOTTOM TIME
** RESIDUAL NITROGEN TIME (RNT)
EXCEPTION (see rule on reverse)
57
26
17
14
11
8
7
6
5
4
223
168
260
300
3
*
133
76
63
46
37
33
28
24
21
*
193
148
100
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
TABLE 2 SURFACE © 2019 NAUI WORLDWIDE
#35502-36 (Rev. 07/19)