Completing A Dive With Mb Levels; Pdis (Profile Dependent Intermediate Stop); Introduction To Pdis - Uwatec Aladin H User Manual

Since level stops are more restrictive
than decompression stops, when all
decompression obligations have been
observed the display changes from STOP
DECO to STOP only.
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3.8.5 Completing a dive with MB
levels
A dive with MB levels is completed the
same way as a dive without MB levels
(see chapter: Diving with your Aladin H,
section: Safety stop timer) except for the
following exceptions:
If the MB level has been reduced during the
dive, the Aladin H will display a flashing MB
level symbol and the current MB level for
5 minutes after reaching the surface. The
dive is then completed and the Aladin H
changes to user mode with the MB level
switching back to the original MB setting.
Repetitive dives and MB levels: If during
a dive a level stop is ignored and you start
another descent shortly afterwards, the
Aladin H might immediately request level
stops. To complete the dive with the initially
set MB level all level stops must be observed.
3.9 PDIS (Profile Dependent
Intermediate Stop)
3.9.1

Introduction to PDIS

The main purpose of a dive computer is to
track your nitrogen uptake and recommend
a safe ascent procedure. Diving within the so
called no-stop limits means that at the end
of the dive you can ascend directly to the
surface, albeit at a safe ascent rate, while for
dives outside of the no-stop limit (so-called
decompression dives), you must perform
stops at certain depths below the surface and
allow time for excess nitrogen to be expelled
from your body before finishing the dive.
In both cases, it can be beneficial to stop
for a few minutes at an intermediate depth
between the maximum attained depth
during the dive and the surface or, in case
of a decompression dive, the first (deepest)
decompression stop.
An intermediate stop of this kind is beneficial
as soon as the ambient pressure at that
depth is low enough to ensure that your
body is predominantly off-gassing nitrogen,
even if under a very small pressure gradient.
In such a situation, you can still cruise along
the reef and enjoy the dive while your body
gets a chance to slowly release nitrogen.
ALADIN H USER MANUAL