SUUNTO FAVOR S - Manual (Page 58)

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To perform these calculations, the dive computer 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 instrument includes the same six compartments, and two additional compartments for an increased range of the mathe-
matical model. The calculations are based on all eight compartments for all phases of diving, including surface intervals and
repetitive dives. The dive computer’s half times range from 2.5 to 320 minutes. The multi-level tissue calculations are based
on modified Haldanean principle.
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 instrument 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 dive computer are reduced according to the lower
ambient pressure. As a result the allowed no-decompression limits are considerably reduced.