18-14 Change A
U.S. Navy Diving Manual—Volume 4
18-4.5
Transit with Excursion Limits. A 20 foot maximum depth for transit with one
excursion, if necessary, will be the preferred option in most combat swimmer
operations. When operational considerations necessitate a descent to deeper than
20 fsw for longer than allowed by the excursion limits, the appropriate single-
depth limit should be used (paragraph 18-4.6).
18-4.5.1
Transit with Excursion Limits Definitions. The following definitions are illus-
trated in Figure 18-3:
Transit is the portion of the dive spent at 20 fsw or shallower.
Excursion is the portion of the dive deeper than 20 fsw.
Excursion time is the time between the diver’s initial descent below 20 fsw
and his return to 20 fsw or shallower at the end of the excursion.
Figure 18-3. Example of Transit with Excursion.
Table 18-5. Single-Depth Oxygen Exposure Limits.
Depth
Maximum Oxygen Time
25 fsw
240 minutes
30 fsw
80 minutes
35 fsw
25 minutes
40 fsw
15 minutes
50 fsw
10 minutes
