Cochran Nemesis IIa NITROX, Руководство пользователя

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The NEMESIS™ IIa NITROX: Overview
In addition to its standard time/depth-based decompression algorithm, the NEM-
ESIS™ IIa NITROX has incorporated the influence of additional physiological factors
such as Altitude, Temperature, Ascent Rate, and Workload. However, the NEMESIS™
IIa NITROX allows the diver, via the optional Analyst PC Interface, to disable the Tem-
perature and/or Workload decompression compensation should the diver deem a
particular diving situation would so warrant. Calculation of Central Nervous System
Oxygen Toxicity (CNS), Mission Oxygen Tolerance Units (OTU's), and the Partial Pres-
sure of Oxygen (PPO2) is yet another added feature of this algorithm. Twelve half-time
compartments ranging from 5 minute to 480 minute theoretical tissue groups are
used. An added degree of conservatism from 0 to 50% may also be added to the base
algorithm if the diver should so desire. You will find that this unit is extremely user
friendly and can be customized to your individual diving conditions and practices.
Some additional factors that influence the decompression algorithm of your NEM-
ESIS™ IIa NITROX are detailed below.
Altitude Adaptation
The NEMESIS™ IIa NITROX continues to monitor changes in barometric pressure
that may occur during travel to and/or from diving destinations. Should a significant
change in altitude occur due to travel to a higher elevation dive site, your unit will
display the time, in hours, that you should wait before diving in order to "off-gas" all
residual nitrogen present as a result of this altitude change. This "adaptation" time is
displayed as Time-To-Fly. Should you wish to begin diving prior to completing the
adaptation time, the NEMESIS™ IIa NITROX will treat your first dive of the day as a
repetitive dive with appropriate reductions in no-decompression (NDC) limits.
Intelligent Deep-Dive Compensation
Modern research has suggested that failing to make each repetitive dive profile, in a
diving day to a shallower depth (inverted profiles) and/or diving square or "sawtooth"
profiles greatly increases your susceptibility to decompression sickness. Your NEM-
ESIS™ IIa NITROX is constantly monitoring the residual nitrogen in all twelve half-time
compartments and modifies its algorithm to alert you to this danger. The intelligent
deep-dive compensation provides real-time adjustment of this factor based upon
residual nitrogen. It is strongly recommended that you always make your first dive of
a diving day the deepest dive, with each repetitive dive to a shallower depth than that of
the previous dive.
Sea Water/Fresh Water Recognition
As you no doubt learned in your entry-level SCUBA class, there is a difference of
approximately three percent between feet of fresh water and feet of sea water. Your
NEMESIS™ IIa NITROX automatically "senses" the type of water you are in upon
entering the Subsurface Mode and provides depth readings in either feet of fresh
water or feet of sea water. With this unique feature, you are assured of extremely
accurate depth information for the medium of water in which you are diving.