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ALTITUDE DIVING
Atmospheric pressure decreases as Altitude increases above sea level. Weather systems
and ambient temperature also affect barometric pressures. Consequently, Depth reading
instruments that do not compensate for the decrease in ambient pressure indicate Depth
readings shallower than the Depth they are actually at.
Oceanic PDCs automatically compensate for decreased ambient pressures for Altitudes be-
tween 3,000 (915 meters) and 14,000 feet (4,270 meters). Their programs compensate
for high altitudes by reducing No Decompression and Oxygen Exposure Limits (times), thus
adding a larger zone of caution.
DECOMPRESSION MODEL
The decompression models used are based on no decompression multi level repetitive dive
schedules successfully tested and validated.
Using an Oceanic PDC, just as using the U.S. Navy (or other) Decompres-
sion Tables, is no guarantee of avoiding decompression sickness.
Every diver’s physiology is different, and can even vary from day to day. No machine
can predict how your body will react to a particular dive profile.
