Uwatec Aladin A1, User Manual

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49
English
A1 USER MANUAL
4.9.2 Altitude and the
decompression algorithm
Atmospheric pressure is a function of
altitude and weather conditions. This is an
important aspect to consider for diving,
because the surrounding atmospheric
pressure has an influence on on-gassing
and off-gassing of nitrogen in your body.
The A1 divides the possible altitude range
into 5 classes that are illustrated in the
picture below:
Altitude Class Elevation
Barometric
switch point
Dive computer
mode
GAUGE
(no deco data)
SCUBA
SCUBA
SCUBA
SCUBA
The altitude classes are approximate
elevations because the effect of weather
conditions can make the switch point
pressure occur at different levels.
WARNING
At the altitude class 4 or higher the A1
operates in GAUGE mode only (the mode will
switch automatically).
F
NOTE: You can check your current
altitude class and elevation in the
Altimtr menu.
F
NOTE: The A1 deals with altitude
automatically: it monitors the
atmospheric pressure every 60
seconds and if it detects a sufficient
drop in pressure, it does the following:
it indicates the new altitude range and,
if applicable, the prohibited altitude
range; it indicates the desaturation
time, which in this case is an
adaptation time to the new ambient
pressure. If a dive is started during
this adaptation time, the A1 considers
it a repetitive dive since the body has
residual nitrogen.
F
NOTE: A fast descent from mountains
or a fast rise in airplane cabin pressure
may activate the dive mode. The A1
will automatically detect and end this
“dive” after 12 hours, or you may
manually activate the check by a
press-and-hold of both +/UP and -/
DOWN buttons at the same time. This
kind of false dive will not be stored in
the A1 logbook.
4.9.3 Prohibited altitude
Going to altitude, as well as flying after
diving, exposes your body to a reduced
ambient pressure. In a manner similar
to no-fly time, the A1 advises you of the
safe altitudes you can reach after a dive,
and those which are not safe. If you have
to drive over a mountain pass to return
home after a dive, this information can be
quite important and you can check this
information in the planner.