MIXED GAS DIVE MODE ACTIVATION,
MAXIMUM OPERATIONAL DEPTH BASED ON SET O2% (14%), HE2% (32%), AND PO2 (1.4) IS
83.3 M.
If set to MIXED GAS mode, the Suunto HelO2 will additionally show on the alternative display:
•the oxygen percentage, labeled O2%
•the helium percentage, labeled He%
•the set oxygen partial pressure limit, labeled PO2
•the current oxygen toxicity exposure, labeled OLF
•maximum depth
•current time
•water temperature
•dive time
•tank pressure
DOWN BUTTON
TOGGLES
BETWEEN O2:HE,
MAXIMUM DEPTH
TANK PRESSURE
AND CURRENT
TIME.
UP BUTTON
TOGGLES
BETWEEN PO2,
OLF, DIVE TIME
AND WATER
TEMPERATURE.
6.2.3. Oxygen limit fraction (OLF)
If set to MIXED GAS mode, in addition to tracking the diver's exposure to inert gas, the instrument tracks the exposure to oxygen. These calculations are treated as entirely sep- arate 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 calcula- tions. The oxygen toxicity calculations are based on the factors listed in Section 10.3. Oxygen exposure .
6.2.4. Gas change and multiple breathing gas mixes
The Suunto HelO2 allows gas changes to enabled gas mixes during the dive.When the maximum operating depth allows for a gas change, the dive computer prompts you to change the gas. When PO2 permits better decompression gas to be used, the dive computer prompts it automatically if it is set as primary. Gas changes are made by following the procedure below:
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