10
Oxygen Accumulation Bar Graph (O2BG)
The O2 Bar Graph (Fig. 2a) represents oxygen loading, your rela-
tive oxygen tolerance dosage (OTU), showing the maximum of ei-
ther per dive accumulated oxygen, or 24 hour period accumulated
oxygen. As your accumulation increases during the dive, segments
will add to the Bar Graph, and as loading decreases, it will begin to
recede, indicating that additional exposure is allowed.
NOTE: Displays associated with oxygen and the
O2 Bar Graph will only appear if FO2 has been set
at a value other than 'Air' (e.g., a numerical value).
Variable Ascent Rate Indicator (VARI)
The Variable Ascent Rate Indicator (Fig. 2b) provides a visual rep-
resentation of ascent speed (i.e., an ascent speedometer). Green is
a 'normal' rate, yellow a 'caution' rate, and red is 'Too Fast'. The
segments of the Variable Ascent Rate Indicator represent 2 sets of
speeds which change at a reference depth of 60 feet (18 meters).
Refer to the chart for segment values.
WARNING: At depths greater than 60 feet (18
meters), ascent rates should not exceed 60 feet per
minute (18 mpm). At depths of 60 feet (18 meters)
and shallower, ascent rates should not exceed 30
feet per minute (9 meters per minute).
Fig. 2 - O2BG and VARI
Variable Ascent Rate Indicator
Deeper than 60 feet (18 m)
Segments
Ascent Rate =
Displayed
FPM
MPM
0
0-20
0 - 6
1
21-30 6.5-9
2
31-40 9.5-12
3
41-50 12.5-15
451-60 15.5-18
5
>60
>18
60 feet (18 m) & Shallower
Segments
Ascent Rate =
Displayed
FPM
MPM
0
0-10
0 - 3
1
11-15 3.5-4.5
2
16-20 5-6
3
21-25 6.5-7.5
426-30 8-9
5
>30
>9
a
b
