64
SECTION 5,
continued
Accuracy Check
Checking Calibration Accuracy
Return the electrode to the calibration and storage chamber. The
chamber should contain a wet sponge or a small amount of water.
Allow at least 10 minutes for stabilization. The meter should
display
100% saturation
. If not, recalibrate the meter.
Method Performance
Precision
In a single lab using one sample at 7.45 mg/L DO and one sample
at 5.10 mg/L DO, the electrode was moved between the two
samples with no rinsing in between. A single operator with a
single sens
ion
156 meter obtained a standard deviation of
0.03 mg/L DO.
Interferences
Oxidizing gases such as chlorine, chlorine dioxide, sulphur
trioxide, and bromine can react at the cathode to produce positive
interferences. Reducing gases such as hydrogen, hydrogen
17.
Press the
DO
key to
change the display from
concentration in mg/L to
% saturation.
Note: The displayed %
saturation will be based on
a meter calculation for the
equilibrium dissolved
oxygen concentration. The
calculation uses the
sample temperature,
salinity, barometric
pressure, and measured
concentration in mg/L
values. Changing the
entry in Setup 7 will alter
the displayed mg/L or %
saturation.
5
DO
%
