Technical information

20
5 Functions at the surface
UWATEC
®
Smart dive computers
5.1 End of a dive
After reaching the surface (<0.8 m/3 ft) Smart remains in dive mode for 5 min
-
utes. The delay allows for surfacing for a short period for orientation.
After 5 minutes the dive is closed and it is entered into the logbook.
For the calculations of the desaturation and no-fly time it is assumed that the
diver breathes air while on the surface.
5.2 Desaturation time After the dive has been closed
DESAT
,
desaturation time in hours and
minutes and, if available, oxygen toxicity is displayed. Desaturation time is
determined either by oxygen toxicity, nitrogen saturation or the regression of
microbubbles, depending on which requires the longer time. Oxygen toxicity
(<CNS O
2
>) is displayed and adjusted until the value becomes 0%.
Desaturation time is indicated until the next dive or until it reaches zero.
The display is switched off to save energy three minutes after the last manipula
-
tion is made. The calculations are nevertheless continued in the background.
5.3 No-fly time
The <no-fly time> is indicated beside the icon <do not fly>. <No-fly time> is
the time in hours that should pass before a flight and is displayed and adjusted
until the value becomes 0 hours.
Flying while Smart displays <do not fly> may lead
to serious injury or death from decompression sick
-
ness.
DIVE TIME
DEPTH
DECO INFO
MAX.DEPTH
%
C
DIVE TIME
DEPTH
DECO INFO
MAX.DEPTH
NO
CNS O
2
%
h
DESAT
h
%
%
C
DIVE TIME
DEPTH
DECO INFO
MAX.DEPTH
NO
CNS O
2
%
h
DESAT
h
%
%
C
Desaturation time
Oxygen toxicity
Do not fly icon
No-fly time
5.4 Microbubble warning
Through repetitive dives microbubbles accumulate in the lungs if the surface
interval is not long enough. Ignoring decompression stops or ascending at
an excessive ascent rate can also lead to microbubbles in tissues. In order
to reduce the risk of decompression sickness for repetitive dives, the surface
interval should be planned long enough. If Smart calculates that the forma
-
tion of microbubbles occurs during the surface interval, it will advise a diver to
extend the surface interval via the microbubble warning. The duration of the
microbubble warning is visible by entering the dive planner ->
29.
If the <microbubble warning (NO DIVE)> is visible
during the surface interval, the diver should not
undertake another dive.
If the dive is made in spite of the microbubble warning, the diver must cope
with a clearly shorter no-stop time or an extension of decompression. Also,
the duration of the microbubble warning at the end of the dive can increase
considerably.
DIVE TIME
DEPTH
DECO INFO
MAX.DEPTH
NO
NO
CNS O
2
%
DESAT
h
%
%
C
Microbubble
warning
Desaturation time
WARNING
WARNING
WARNING