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ALTITUDE SAMPLING/COMPENSATION
Diving at high altitude requires special knowledge of the variations
imposed upon divers, their activities, and their equipment by the
decrease in atmospheric pressures. AERIS recommends comple-
tion of a specialized Altitude training course by a recognized train-
ing agency prior to diving in high altitude lakes or rivers.
Atmospheric pressure decreases as altitude increases above sea
level. Weather systems and ambient temperature also affect baro-
metric pressures. Consequently, depth reading instruments that do
not compensate for the decrease in pressure indicate depth readings
shallower than the depth they are actually at.
The XR2 automatically compensates for decreased ambient pres-
sure when activated at high altitudes up to 14,000 feet (4,267
meters). Its program contains a high altitude algorithm that re-
duces no decompression and oxygen exposure limits to add a larger
zone of caution.
The XR2
senses ambient pressure when it is activated, every 15
minutes while it is activated, or every 30 minutes when it is not ac-
tivated. At an Altitude of 2,000 feet (610 meters), it will automati-
cally recalibrate itself to measure depth in feet of fresh water rather
than feet of sea water. It will then readjust the no decompression
and oxygen limits at additional intervals of 1,000 feet (305
meters).
