Po2 Alarm; Curve Dive; Ascent Rate - Cressi Archimede II Manual De Instrucciones

NOTE: The result of the computation is the oxygen compo-
sition is approximated to the nearest whole number.
NOTE: The computation of CNS toxicity shown by the rela-
ting graph, takes into account both mixtures used during the
dive. By using highly nitrox mixtures during the decompres-
sion, the toxicity level may be reached during the final phase
of the dive. In this case, the alarm will sound after the seventh
pixel has lit up; the diver must quickly change over to the bot-
tom mixture and the computer must be consequently reset.
m
DANGER: Do not use nitrox mixtures during diving acti-
vities without proper training by certified training agencies.
Related topics:
• 3.1. - AIR DIVE.
• 3.2. - NITROX MIXTURES DIVE.
• 3.3.1. - PO2 partial pressure setting..
• 3.3.2. - Oxygen fraction FO2 setting.
• 3.3.5. - PO2 alarms.
• 4.1.2. - Logbook.

3.3.5. - PO2 alarm.

Archimedes II computer is able to constantly monitor ano-
ther basic parameter relating to oxygen, and that is O2 partial
pressure value (PO2). Oxygen toxicity may be caused both
by an excessive accumulation (CNS toxicity, seen in the pre-
vious chapter) and by exceeding the maximum PO2, which is
exceeding the maximum depth allowed by the mixture used.
As already seen, the PO2 limit value is set by the diver in a
range between 1.0 bar and 1.6 bar. Archimedes II considers
the 1.6 bar value as the partial pressure maximum allowable
limit and, according to the used mixture, automatically signals
the maximum depth which may be reached. Remember that
even by using air, you may reach the oxygen toxicity limit.
Such limit varies according to the set PO2. Archimedes II is
manufactured with a preset value of 1.4 bar, whose corre-
sponding maximum depth is 1834 ft. in air. It is possible to set
the computer on other PO2 values, up to a maximum of 1.6
bar. Archimedes II is equipped with two kinds of PO2 alarms:
1 By reaching the limit depth relating to the set PO2 (from
1.0 bar to 1.6 bar), a sound alarm will start lasting 15
seconds while the display will be flashing, showing the
( ) icon and the reached PO2 limit value, at the top on
the left (picture 16).
2 A second alarm will start by achieving the depth equiva-
lent to PO2 of 1.6 bar and will last 15 seconds. The display
will be flashing and will stop only when the diver will reach
a depth lower than the limit one.
Both alarms will be entered in the Logbook.
Related topics:
• 3.1. - AIR DIVE.
• 3.2. - NITROX MIXTURES DIVE.
• 3.3.1. - PO2 partial pressure setting.
• 4.1.2. - Logbook.

3.4. - Curve dive.

3.4.1. – Ascent rate.
Archimedes II Cressi-sub computer's algorithm considers
different ascent rates according to the depth. The speed is
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