UP BUTTON
TOGGLES
BETWEEN PO
2
,
OLF, DIVE TIME
AND WATER
TEMPERATURE.
DOWN BUTTON
TOGGLES
BETWEEN O
2
,
MAXIMUM DEPTH
TANK PRESSURE
AND CURRENT
TIME.
6.2.3. Oxygen limit fraction (OLF)
If set to NITROX mode, in addition to tracking the diver's exposure to nitrogen, the
instrument tracks the exposure to oxygen. These calculations are treated as entirely
separate functions.
The dive computer calculates separately for Central Nervous System oxygen toxicity (CNS)
and Pulmonary Oxygen toxicity, the latter measured by the addition of Oxygen Toxicity
Units (OTU). Both fractions are scaled so that the maximum tolerated exposure for each
is expressed as 100%.
The Oxygen Limit Fraction (OLF) displays only the value of the higher of the two
calculations. The oxygen toxicity calculations are based on the factors listed in Section
9.3 “Oxygen exposure”.
6.2.4. Gas change and multiple breathing gas mixes
The Suunto Cobra2 allows gas changes to enabled gas mixes during the dive. Gas changes
are made by following the procedure below:
CHANGING GAS MIX. SCROLL
THROUGH ENABLED MIXES BY
PRESSING THE UP OR DOWN
BUTTONS. SELECT NEW MIX BY
PRESSING THE SELECT BUTTON.
NOTE
Mix number, O
2
%, and PO
2
for the mixes are shown when scrolling.
If the set PO
2
limit is exceeded , it will be shown with the PO
2
value
blinking. The dive computer does not allow you to change to a gas
whose set PO
2
is exceeded. In such a case, the mix is shown but
cannot be selected.
NOTE
If no button is pressed in 15 seconds, the dive computer will go back
to the dive display without changing the gas mix. Upon ascent, the
computer prompts you to change gas when the PO
2
level you have
set for the next mix allows a gas change. The prompt is an audible 3
beeps and the current O
2
mix starts to blink.
6.3. Diving in GAUGE mode (DIVEgauge)
If set to GAUGE mode, the dive computer can be used as a bottom timer.
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