Uwatec Galileo 2, Руководство пользователя

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GALILEO 2 (G2) USER MANUAL
3 .3 .4 Decompression dives in
mountain lakes
In order to ensure optimal decompression,
even at higher altitudes, the decompression
stop starts from 2m/7ft in altitude classes
1, 2 and 3.
If atmospheric pressure is below 610mbar
(altitude higher than 4000m/13300ft), no
decompression calculation is carried out
by the G2 (automatic Gauge mode). In
addition, the dive planner is not available in
this altitude class.
3 .4 Diving with nitrox
Nitrox is the term used to describe
breathing gases made of oxygen-nitrogen
mixes with the oxygen percentage higher
than 21% (air). Because nitrox contains
less nitrogen than air, there is less nitrogen
loading on the diver’s body at the same
depth as compared to breathing air.
However, the increase in oxygen
concentration in nitrox implies an increase
in oxygen partial pressure in the breathing
mix at the same depth. At higher than
atmospheric partial pressures, oxygen
can have toxic effects on the human body.
These can be grouped into 2 categories:
1. Sudden effects due to oxygen
partial pressure over 1.4bar.
These are
not related to the length of the exposure
to high oxygen partial pressure. Sudden
effects can vary and depend on the exact
level of partial pressure they happen at. It is
commonly accepted that partial pressures
up to 1.4bar are tolerable during the active
part of the dive, and maximum oxygen
partial pressures up to 1.6bar during the
decompression.
2. Long exposure effects to oxygen
partial pressures over 0.5bar due to
repeated and/or long dives.
These can
affect the central nervous system and
cause damage to lungs or to other vital
organs. Long exposures can be divided
between more severe Central Nervous
System effects and less dangerous long-
term Pulmonary Toxicity effects.
The G2 treats high ppO
2
and long exposure
effects in the following ways:
• Against sudden effects.
The G2 has
an MOD alarm set for a user-defined
ppO
2
max. As you enter the oxygen
concentration for the dive, the G2 shows
you the corresponding MOD for the defined
ppO
2
max. The default value of ppO
2
max
from the factory is 1.4bar. This can be
adjusted to your preference between
1.0 and 1.6bar. It can also be turned off.
Please refer to chapter:
ppO
2
max for more
information on how to change this setting.
• Against long exposure effects. The
G2 “tracks” the exposure by means of
the CNS O
2
clock. At levels of 100% and