Suunto EON - Oxygen Exposure; Decompression Dives

CAUTION: Always use the same personal and altitude adjustment settings for the actual
dive and for the planning. Increasing the personal adjustment setting from the planned
setting as well as increasing the altitude adjustment setting can lead to longer
decompression times deeper and thus to larger required gas volume. You can run out of
breathing gas underwater if the personal adjustment setting has been changed after dive
planning.
4.10.4. Oxygen exposure
The oxygen exposure calculations are based on currently accepted exposure time limit tables
and principles. In addition to this, the dive computer uses several methods to conservatively
estimate the oxygen exposure. For example:
•
The displayed oxygen exposure calculations are raised to the next higher percentage
value.
•
The CNS% limits up to 1.6 bar (23.2 psi) are based on 1991 NOAA Diving Manual limits.
•
The OTU monitoring is based on the long-term daily tolerance level and the recovery rate
is reduced.
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. For example, the following
information is provided before and during a dive when the computer is set to Air/Nitrox or
Trimix (if helium is activated in use):
•
The selected O
2
% (and possible helium %)
•
CNS% and OTU (visible only after your customization in Suunto app)
•
Audible
notification when CNS% reaches 80%, then warning when 100% limit is exceeded
•
Notification when OTU reaches 250 and then warning when 300 limit is exceeded
•
Audible alarm when pO
2
value exceeds the preset limit (pO
2
high alarm)
•
Audible alarm when pO
2
value is < 0.18 (pO
2
low alarm)
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.
4.11. Decompression dives
When on a decompression (deco) dive you exceed the no decompression limit, Suunto EON
Steel Black provides the decompression information required for ascent. Ascent information is
always presented with two values:
•
ceiling: depth that you should not go above
•
asc. time: optimum ascent time in minutes to surface with given gases
WARNING: NEVER ASCEND ABOVE THE CEILING! You must not ascend above the
ceiling during your decompression. In order to avoid doing so by accident, you should stay
somewhat below the ceiling.
On a decompression dive, there can be three kinds of stops:
•
Safety stop: this is a recommended three-minute stop for every dive over 10 meters (33 ft).
•
Deepstop: this is a recommended stop when you dive deeper than 20 m (66 ft).
Suunto EON Steel Black
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