LaMotte 2020wi Portable Turbidity Meters - Manual (Page 8)

be very bad! This is not a useful measure of the performance of a test
method.
Repeatability: Repeatability is the within-run precision.
5 A run is a
single data set, from set up to clean up. Generally, one run occurs
on one day. However, for meter calibrations, a single calibration is
considered a single run or data set, even though it may take 2 or 3 days.
Reproducibility: Reproducibility is the between-run precision. 6
Detection Limit (DL): The detection limit (DL) for the 2020we/wi
is defi ned as the minimum value or concentration that can be
determined by the meter, which is greater than zero, independent of
matrix, glassware, and other sample handling sources of error. It is the
detection limit for the optical system of the meter.
1 CFR 40, part 136, appendix B
2 Statistics in Analytical Chemistry: Part 7 – A Review, D. Coleman and L
Vanatta, American Laboratory, Sept 2003, P. 31.
3 Skoog, D.A., West, D. M., Fundamental of Analytical Chemistry, 2 nd ed.,
Holt Rinehart and Winston, Inc, 1969, p. 26.
4 Statistics in Analytical Chemistry: Part 7 – A Review, D. Coleman and L
Vanatta, American Laboratory, Sept 2003, P. 34.
5 Jeffery G. H., Basset J., Mendham J., Denney R. C., Vogel’s Textbook of
Quantitative Chemical Analysis, 5 th ed., Longman Scientifi c & Technical,
1989, p. 130.
6 Jeffery G. H., Basset J., Mendham J., Denney R. C., Vogel’s Textbook of
Quantitative Chemical Analysis, 5 th ed., Longman Scientifi c & Technical,
1989, p. 130
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