Performance Verification Statement for the Precision Measurement Engineering miniDOT Dissolved Oxygen Sensors

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Ref. No. [UMCES] CBL 2016-011
ACT VS16-02
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Figure A. Response of the PME miniDOT (sn 7392-340698) to changing dissolved oxygen
concentrations at 15.4 oC and S=0.00. Top Panel: Time series of instrument readings and Winkler
reference samples drawn at level of sensor foil in well-mixed test tanks. The large offsets for the
final two concentrations are suspected to indicate bubbles from the sparging gas being trapped on
sensor foil and contaminating the measurement. Bottom Panel: Corresponding offset between
instrument reading and Winkler DO reference sample during exposure trial. Dotted line represents
zero offset from reference. Offsets beyond +/- 2 mg/L are excluded for clarity.