Decompression Model; Tissue Compartment Control; No Decompression Limits - Sherwood Scuba Insight Manual Manual

DECOMPRESSION MODEL

The Decompression Model used by the INSIGHT is based on the no decompression multilevel repeti-
tive dive schedules successfully tested by Dr. Ray Rogers and Dr. Michael Powell. These tests did not
include repetitive dives deeper than 90 FT (27 M) or decompression dives. Due to the present unavail-
ability of statistical data, INSIGHT decompression predictions are based on U.S. Navy theory.

TISSUE COMPARTMENT CONTROL

The INSIGHT tracks twelve tissue compartments with halftimes ranging from 5 to 480 minutes. The
Nitrogen Bar Graph always displays the controlling compartment that is the only one important at that
INSIGHT USN
time. Think of the Nitrogen Bar Graph as twelve separate transparent displays laid on top of one an-
Depth NDL-mins. NDL
other. The compartment that has filled up fastest is the only one the viewer can see from the top.
FT (M) Eng (Metric) mins.
30 (9) 260 (283) - - -
35 - - - 310
40 (12) 137 (144) 200
At any particular point, one compartment may be absorbing nitrogen, while another that was previ-
50 (15) 81 (85) 100
ously higher may be off gassing. One compartment "hand over" control to another compartment at a
60 (18) 57 (59) 60
70 (21) 40 (41) 50
different depth. This feature of the Decompression Model is the basis of multilevel diving, one of
80 (24) 30 (32) 40
90 (27) 24 (25) 30
the most important contributions the INSIGHT offers you.
100 (30) 19 (20) 25
110 (33) 16 (17) 20
120 (36) 13 (14) 15
NO DECOMPRESSION LIMITS (NDLS)
130 (39) 11 (11) 10
140 (42) 9 (9) 10
Note how the No Decompression Limits for the INSIGHT are contrasted with the U.S. Navy limits
150 (45) 8 (8) 5
(Fig. 84). The INSIGHT's Dive Planner does not scroll past 190 FT (57 M), or to depths at which
160 (48) 7 (7) 5
170 (51) 7 (6) 5
projected dive time is less than one minute .
180 (54) 6 (6) 5
190 (57) 5 (5) - - -
Fig. 84 - NDL
Comparison
80