Operating instructions

Altitude Diving
The mathematical model in the Matrix accounts for the reduced no-decompression time available at higher elevations
based on the National Oceanic and Atmospheric Administration (NOAA) guidelines. When diving in high altitude lakes or
rivers (from 3,000 to 14,000 ft; 915 to 4267 m), the Matrix automatically adjusts to these conditions providing correct
depth and reduced no-decompression times. At altitudes over 3,000 ft (915 m), depth calibration automatically
changes to read in feet/meters of freshwater (FFW, MFW) instead of feet/meters of seawater (FSW, MSW).
WARNING: Until it has shut itself off, you must not use the Matrix at an altitude other than
the altitude where it was originally activated. Doing so will result in an error equal to the
difference in barometric pressure, and possibly a false dive mode.
SURFACE MODE
The Matrix enters Surface Mode when (1) the computer completes the startup/
diagnostic procedures, or (2) ten minutes after completing a dive deeper than 5 feet,
or 1.5 meters. While in Surface Mode, the Matrix alternates between the following
three informational displays:
1: Standard surface information
2. Pre-dive planning sequence
3. Wait-to-fly time
Standard Surface Information
The first display to appear in Surface Mode is standard surface information (figure 5).
This display gives the following information:
a. Surface Time. Notice how the wave icon is below the time display, meaning that
it is “time above the water.” The time is displayed in HH:MM
b. Dive number. The computer displays the number of the dive just completed. After
startup, this number will be 0. The Matrix counts up to 10 dives. After dive 10, it
cycles back to 1.
c. Depth. Depth always shows 00 ft., or 0.0 m during Surface Mode.
d. Compartment Loading Bar Graph (CLBG). The CLBG is only displayed after
making a dive. During the surface interval, the CLBG starts to recede, indicating
that you are off-gassing nitrogen. When you first turn on the Matrix, you will not
see the CLBG.
Wait-to-fly Time
The second display to appear during Surface Mode is wait-to-fly time (figure 6). It
appears about twenty seconds after the standard surface information, and only
appears after a dive. Only two elements appear: (a) the no-fly icon (airplane icon) and
(b) the wait-to-fly time.
Wait-to-fly time starts to count down from 23:50 (24 hours less the first 10 minutes of
surface interval). At the 12:00 mark, the Matrix shuts down internally, but continues to
display the countdown from 11:59 to zero. Therefore, if you want to make a dive while
wait-to-fly time is 12 hours or less, you must first reactivate the computer by pressing
the neon-yellow button.
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Wait-to-fly guidelines
In 1990, the Undersea and Hyperbaric Medical Society (UHMS) published a set of
guidelines for lowering the chance of decompression sickness due to flying too
soon after diving. The UHMS suggests divers using standard air tanks and exhibit-
ing no symptoms of decompression sickness wait 24 hours after the last dive to fly
in an aircraft with an internal cabin pressure of 8,000 feet (2438 m) or less. The
only two exceptions to this recommendation are:
Figure 6
Wait-to-fly Time
Figure 5
Standard Surface mode
Imperial