Suunto Gekko User Manual page 13

However, when the gas mix is altered, the oxygen content of the mix is generally
increased. This increase exposes the diver to an oxygen toxicity risk not usually
considered in recreational diving. In order to manage this risk, the dive computer
tracks the time and intensity of the oxygen exposure and provides the diver with
information to adjust the dive plan in order to maintain oxygen exposure within
reasonably safe limits.
In addition to the physiological effects of enriched air on the body there are op-
erational considerations to be addressed when handling altered breathing mixes.
Elevated concentrations of oxygen present a fi re or explosion hazard. Consult the
manufacturer of your equipment in regards to its compatibility with nitrox.
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