Suunto HELO2 Scuba Diving Equipment User Manual


 
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 at the deep stop
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
WARNING
YOUR ACTUAL ASCENT TIME MAY BE LONGER THAN DIS-
PLAYED BY THE INSTRUMENT! The ascent time will increase if
you:
remain at depth
ascend slower than 10 m/33 ft per minute
make your decompression stop deeper than at the ceiling
do not use optimal decompression gas
These factors will also increase the amount of gas required to reach
the surface.
Ceiling, ceiling zone, floor and decompression range
When in decompression, it is important that you understand the meaning of ceiling, floor,
and decompression range.
The ceiling is theshallowest depth to which youshould ascend when in decompression.
At this depth, or below, you must perform all stops
The ceiling zone is the optimum decompression stop zone. It is the zone between the
minimum ceiling and 1.2 m/4 ft below the minimum ceiling
The floor is the deepest depth at which the decompression stop time will not increase.
Decompression will start when you pass this depth during your ascent
The decompression range is the depth range between the ceiling and floor. Within this
range, decompression takes place. However, it is important to remember that the de-
compression will be very slow at, or close to, the floor
The depth of the ceiling and floor will depend on your dive profile. The ceiling depth will
be fairly shallow when you enter the decompression mode, but if you remain at depth, it
will move downward and the ascent time will increase. Likewise, the floor and ceiling may
change upwards while you are decompressing.
When conditions are rough,it may be difficult tomaintain a constant depth near the surface.
In such cases, it is more manageable to maintain an additional distance below the ceiling,
to make sure that the waves do not lift you above the ceiling. Suunto recommends that
decompression takes place deeper than 4m/13 ft, even if the indicated ceiling is shallower.
NOTE
It will take more time and more gas to decompress below the ceiling
than at the ceiling.
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