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surface interval increases, so does the available dive time for the next dive.
To perform these calculations, the SOLUTION
á
continuously models the
absorption and release of excess nitrogen from theoretical compartments. Each
compartment absorbs and releases nitrogen at a different rate. The compartments
that absorb and release nitrogen rapidly are believed to have a high tolerance for
excess nitrogen, whereas compartments that absorb and release nitrogen more
slowly are believed to be more sensitive.
The no-decompression limits in the U.S. Navy tables are based upon six theoretical
compartments for single dives, and one compartment for surface intervals and
repetitive dives. If you are familiar with table theory, you may know that they are
characterized by half times (i.e. the time required for 50 % equilibration to a
pressure change) ranging from 5 minutes to 120 minutes.
The SOLUTION
á
includes the same six compartments, and three additional
compartments for an increased range of the mathematical model. The calculations
are based on all nine compartments for all phases of diving, including surface
intervals and repetitive dives. The SOLUTION
á
's half times range from 2.5 to 480
minutes.
Altitude Diving
The atmospheric pressure is lower at high altitudes than at sea level. After traveling
to a higher altitude, the diver will have additional nitrogen in his body, compared to
the equilibrium situation at the original altitude. This "additional" nitrogen is released
gradually in time and equilibrium is reached within a couple of days.
Before high altitude diving the SOLUTION
á
must be set to high altitude diving
mode to take this into account. The maximum partial pressures of nitrogen allowed
by the mathematical model of the SOLUTION
á
are reduced according to the lower
ambient pressure.
As a result the allowed no-decompression limits are considerably reduced.
Surface Intervals
The SOLUTION
á
requires a minimum surface interval of 10 minutes between
dives. If a surface interval is shorter than 10 minutes, the SOLUTION
á
dive
counter and dive timer treat the next dive as a continuation of the previous dive. It
adds the dive times, and calculates no-decompression limits or decompression
stops based on excess nitrogen absorbed on both dives. In this regard, it is similar
to the U.S. Navy tables.
