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Ref. No. [UMCES] CBL 2016-011
ACT VS16-02
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Data validation uses the outputs from data verification and included inspection of the verified
field and laboratory data to determine the analytical quality of the data set. A representative set of
approximately 10% of the data on core parameters was traced in detail from raw data from field and
laboratory logs and instrument readouts through data transcription or transference through data
manipulation through data reduction to summary data, data calculations, and final reported data.
Data validation established:
•
Required sampling methods were used;
•
Sampling procedures and field measurements met performance criteria;
•
Required analytical methods were used;
Data validation confirmed that ACT’s sample measurement system performed in accordance
with the performance goals specified in the ACT QAPP and the DO Test Protocols and that the data
were accumulated, transferred, reduced, calculated, summarized, and reported correctly. There is
sufficient documentation of all procedures used in the data collection and analysis to validate that
the data were collected in accordance with the verification’s quality objectives.
A Data Quality Assessment (DQA), the third and final process of the overall data assessment,
is a scientific and statistical evaluation of validated data to determine if the data are of the right type,
quality, and quantity to support conclusions on the performance of the DO sensors. The DQA
determined that ACT’s data quality objectives, described in Section 3.4 of the ACT QAPP, were
achieved. This evidence supports conclusions that:
•
The sampling design performed very well and was very robust with respect to changing
conditions.
•
Sufficient samples were taken to enable the reviewer to see an effect if it were present.
•
Data on the performance of the DO sensors are unambiguous, and the vendors and buyers can
make informed choices about the performance of a sensor with a high level of certainty.
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Carignan, R., Blais, A.M., and Vis, C. 1998. Measurement of primary production and community
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Carritt, D.E., and Carpenter, J.H. 1966. Comparison and evaluation of currently employed
modifications of the Winkler method for determining dissolved oxygen in seawater; a NASCO
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