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ALTITUDE SAMPLING/COMPENSATION
Atmospheric pressure decreases as altitude increases above sea level. Weather systems and ambi-
ent temperature also affect barometric 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 ATMOS 2 automatically compensates for decreased ambient pressure when activated at high
altitudes up to 14,000 feet (4,270 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 ATMOS 2 senses ambient pressure when it is activated, every 15 minutes while it is acti-
vated, or every 30 minutes when it is not activated. At an Altitude of 2,000 feet (610 meters), it
will automatically 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). Therefore, when returning to lower Altitudes, diving should not be con-
ducted until the unit automatically clears of any residual nitrogen and oxygen loading and resets
to operate at the new lower Altitude.
WARNING: The ATMOS 2 will not sense ambient pressures or provide Alti-
tude compensation when it is wet. DO NOT dive at any different Altitude until
the unit shuts off and is reactivated at the new Altitude. If the unit is acti-
vated at elevations higher than 14,000 feet (4,270 meters), it will perform a di-
agnostic check followed by immediate shutdown.
