Thermo Orion 410Aplus, Instruction Manual

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Orion Benchtop pH/ISE Meter Instruction Manual
Other Measurement Modes 55
12. Insert the reservoir (funnel) into a BOD bottle containing enough
water to just cover the bottom. Insert the electrode, making sure
that the electrode tip is not immersed in the water and does not have
water droplets clinging to the outside of the membrane. Let stand
approximately 30 minutes to ensure water saturation of air in the
BOD bottle. This bottle should be used for storage between
measurements.
13. Turn the electrode mode switch to the AIR position. If measurements
are being made at sea level, use the AIR calibration control on the
electrode to set the pH meter reading to the prevailing barometric
pressure in mm Hg (divided by 100). If the barometric pressure is
unknown, the elevation is above sea level or the sample has a salinity
greater than two parts per thousand, consult
Table 1 found in the
Orion 9708 Instruction Manual to obtain the correct AIR
setting. Turn the electrode mode switch to H
2
O for sample analysis.
14. Record direct ppm reading from meter.