Oxygen Equipment User Manual

8
be performed when the geographic elevation at which the product is being
used changes by more than 500 feet.
The sensor is best calibrated while mounted in the industry standard,
15mm I.D. “T” adapter. As in normal operation, the oxygen sensor
responds best when installed in a vertical position with the sensor facing
down.
In addition, calibration is recommended if the user is unsure when the last
calibration procedure was performed or if the measurement value
displayed is in question.
It is best to calibrate the MAXO
2
 Monitor to a known documented oxygen
concentration at a pressure and flow similar to your clinical application.
Calibrating the MAXO
2 at lower concentrations with a known oxygen
value is also acceptable and may provide additional accuracy if the
calibration gas is closer to the environment in which the MAXO
2 will be
used. A “known” value of oxygen is defined as an oxygen source which
has a traceable certificate and / or USP certification.
Note: Before beginning calibration the MAX-250E sensor must be in
thermal equilibrium. You may also need to be aware of other factors
which affect device calibration values. For more information, refer to
“Factors Influencing Calibration and Performance” in this manual.
2.2.2 To Calibrate the MAXO
2
 Monitor
1) Place the external probe in a stream of gas of known oxygen
concentration. Expose the sensor to the calibration gas at a
regulated pressure and flow.
2) Using the ON/OFF key, make sure the unit is in the power on mode.
3) Allow the oxygen reading to stabilize. This will normally take about
30 seconds or more.
4) Press the LOCK/UNLOCK key to unlock the keypad. The
"LOCKED" icon will disappear from the display.
5) Press the CALIBRATE key on the keypad. The word "CAL" will
appear on the display for about 1 second and then the "%" sign will
start to flash.
R213M05H.qxd 6/26/2006 9:04 AM Page 7