SCUBAPRO-UWATEC galileo luna, Manual

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1. Introduction to Galileo 1. Introduction to Galileo
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30m/100ft would result in the same deep
stop of 15m/50ft.
With PDIS, as the name suggests, Galileo
interprets your dive profile and suggests
an intermediate stop that is a function of
your nitrogen uptake so far. The PDI stop
will therefore change through the course of
the dive to reflect the continuosly changing
situation in your body. Along the same lines,
PDIS will account for the accumulated
nitrogen from previous dives, hence
PDIS is also repetitive-dive dependent.
Conventional deep stops completely ignore
these facts.
The following figure quantifies the extent
of PDIS and illustrates its dependence on
cumulative nitrogen uptake for two sample
dive profiles. This figure also demonstrates
the conceptual difference between PDIS
and the rather rudimental “deep” stops.
Specifically, the figure compares two dive
profiles to a maximum depth of 40m/132ft
but otherwise very different. Profile 1 stays
at 40m/132ft for 7 minutes, then ascends
to 30m/100ft for 3 minutes, followed by
12 minutes at 20m/65ft. Profile 2 stays
less than two minutes at 40m/132ft, then
ascends to 21m/69ft and stays there for
33 minutes. Both dive profiles are no-stop
dives to the limit of entering decompression.
The solid line with triangles represents the
PDIS depth as displayed on the computer
screen during the course of the dive for
profile 1, the dotted line with triangles
represents the PDIS depth as displayed on
the computer screen during the course of
profile 2. One can see that the displayed
PDIS depth increases as more nitrogen
is accumulated in the body, but does so
very differently in the two dives due to the
different exposure in the two profiles. The
PDI stop is carried out at 25 minutes for
profile 1 and at 37 minutes for profile 2,
followed by the safety stop at 5m/15ft.
The solid line with open circles on the other
hand represents the depth that would be
displayed by a computer following the
conventional deep stop method, and it
would be the same for the two dive profiles.
Deep stops completely ignore any facts
about the dives themselves aside for the
max depth.