Suunto SS020393000 Scuba Diving Equipment User Manual


 
3.21.3 Oxygen exposure
The oxygen exposure calculations are based on currently accepted
exposure time limit tables and principles.
The dive computer calculates separately the Central Nervous System
oxygen toxicity (CNS) and the Pulmonary Oxygen toxicity, the latter
measured by the addition of Oxygen Toxicity Units (OTU).
Both fractions are scaled so that the diver’s maximum tolerated
exposure for each is 100%.
Suunto D4i does not display CNS% or OTU% but instead displays
the larger of the two in the OLF% field. OLF% value is the Oxygen
limit fraction or Oxygen Toxicity Exposure.
For example, it the diver’s maximum tolerated exposure for CNS% is
85% and the maximum tolerated exposure for OUT% is 80% the
OLF% displays the largest scaled value, here 85%.
Oxygen related information displayed by the dive computer is also
designed to ensure that all warnings and displays occur at the
appropriate phases of a dive.
WARNING:
WHEN THE OXYGEN LIMIT FRACTION INDICATES
THAT THE MAXIMUM LIMIT IS REACHED, YOU MUST IMMEDIATELY
TAKE ACTION TO REDUCE OXYGEN EXPOSURE. Failure to take
action to reduce oxygen exposure after a CNS%/OTU warning is
given can rapidly increase the risk of oxygen toxicity, injury, or
death.
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