SUUNTO D4 - Manual (Page 48)

5.11. Deep stops
Deep Stops are safety stops that occur deeper than traditional stops, with the purpose
of minimizing microbubble formation and excitation.
The Suunto RGBM model calculates deep stops iteratively, placing the first stop about
halfway between the maximum depth and the ceiling depth. After the first Deep Stop
is completed, another Deep Stop will be prompted halfway to the ceiling, and so on
until the ceiling depth is reached.
The Deep Stop length can be set to 1 or 2 minutes.
NOTE With Deep Stops on, the Recommended Safety Stops will still be
activated at the end of the dive.
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