20
5 Functions at the Surface
III Uwatec
®
Smart dive computers
5.1 End of a dive
After reaching the surface (<0.8 m/3 ft) Smart remains on for 5 minutes after
the dive is terminated. The delay allows for surfacing for a short period for ori-
entation.
When the dive is closed after 5 minutes, it is entered into the logbook.
For the calculations of the desaturation and No Fly Time it is assumed that the
diver breathes air.
5.2 Desaturation time
After the dive has been closed
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 saturati-
on (<CNS O
2
LIMIT>) 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 manipu-
lation 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 the Smart displays <Do not fly> may
lead to serious injury or death from decompression
sickness.
DESAT
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 Warning of bubbles
Through repetitive dives microbubbles accumulate in the lungs if the surface
interval is not long enough. Ignoring decompression stops or an excessive
ascent rate can also lead to bubbles in tissues. In order to reduce the risk of
decompression sickness for future repetitive dives, the surface interval should
be planned long enough to reduce the risk of decompression sickness. If Smart
calculates that the formation of microbubbles occur during the surface inter-
val, it will advise a diver to extend the surface interval. Duration of the micro-
bubble warning: see page 27.
If the <bubble 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 bubble warning, the diver must cope with a
clearly shorter no-stop time or an extension of decompression. The duration of
the bubble warning at the end of the dive can increase considerably.
DIVE TIME
DEPTH
DECO INFO
MAX.DEPTH
NO STOP
%
NO
Microbubble
warning
Desaturation time
WARNING
WARNING
WARNING
Eg-SMART III+IV 13.10.2001 11:16 Uhr Seite 20
