Suunto D4 manual Decompression dives

6.1.4. Decompression dives

When your NO DEC TIME becomes zero, your dive becomes a decompression dive so you must perform one or more decompression stops on your way to the surface. The NO DEC TIME on your display will be replaced by an ASC TIME, and a CEILING notation will appear. An upward pointing arrow will also prompt you to start your ascent. If you exceed the no-decompression limits on a dive, the dive computer will provide the decompression information required for ascent. After this, the instrument will continue to provide subsequent interval and repetitive dive information.

Rather than requiring you to make stops at fixed depths, the dive computer lets you decompress within a range of depths (continuous decompression).

The ascent time (ASC TIME) is the minimum amount of time needed to reach the surface in a decompression dive. It includes:

•the time needed to ascend to the ceiling at an ascent rate of 10 m/33 ft per minute. The ceiling is the shallowest depth to which you should ascend

•the time needed at the ceiling

•the time needed at the Mandatory Safety Stop (if any)

•the time needed to reach the surface after the ceiling and Safety Stops have been completed

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