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Diving Terms Used by this Watch
The following provides an explanation of the diving terms displayed by this watch along with their basic meanings.
<Algorithm>
This watch employs the calculation formula of the Canadian Defense and Civil Institute of Environmental Medicine (DCIEM).
<Scuba Diving and Skin Diving>
This watch automatically distinguishes between skin diving and scuba diving according to the following conditions, and records log data separately for each type of diving.
•Scuba diving: Continuously diving for 3 minutes or more to a depth of 1 m (4 ft) or more
•Skin diving: Continuously diving for less than 3 minutes to a depth of 1 m (4 ft) or more
<No-Decompression Diving and No-Decompression Limit (NDL) Time>
<One Dive>
In this watch, one dive constitutes the time from initially diving to a depth of 1 m (4 ft) (start of dive) from the preliminary dive mode state to the time the dive mode is terminated (end of dive).
<NITROX Diving>
NITROX diving refers to diving in which a mixed gas of oxygen and nitrogen is used that has a higher oxygen concentration than ordinary air tanks. This watch allows the oxygen concentration (O2%) to be set within the range of 22% to 50% in the dive plan mode.
*NITROX diving reduces the diver’s risk of decompression sickness by reducing the nitrogen ratio (%) to a level lower than ordinary AIR diving. However, increasing the oxygen ratio (%) also invites the risk of “oxygen toxication” for the diver, a condition that is unpredictable in the case of AIR diving. In the case of performing NITROX diving, always make sure to receive safety training relating to NITROX diving in advance.
<AIR Diving>
AIR diving refers to diving using an ordinary air tank (compressed air having an oxygen concentration of 21%). This watch uses the term AIR diving to distinguish it from NITROX diving in which the oxygen concentration is 22% or higher.
<High-Altitude Diving and Altitude Setting>
*Since atmospheric pressure at high altitudes differs from that at lower altitudes where ordinary diving is performed,
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