Quality Control Samples in Ecology |
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Sample type |
Description |
Assessment Parameter |
collocated sample |
one of 2 or more independent samples collected so that each is equally representative for a given variable at a common space and time |
used to estimate overall precision |
Filed Duplicate |
2 samples taken from and representative of the same population and caqrried through all steps of sampling and analysis in an identical manner |
used to assess total variance of the method, including sampling and analysis |
Replicate sample |
2 or more samples representing the same population, time and place, which are independently carried through all steps of sampling and measurement process in an identical manner |
used to assess total variance |
Split Sample |
2 or more representative portions taken from a sample or subsample and analyzed by different analysts or laboratories |
used to replicate the measurements of interest |
Spiked Sample |
A sample prepared by adding a known mass of target analyte to a specified amount of matrix sample for which an independent estimate of target analyte concentration is available |
used to determinate the effect of matrix on the method recovery efficiency |
Calibration check Sample |
A reference material used to check that the calibration is acceptable |
used to ensure that the measurement system is under control |
Quality Control Sample |
An uncontaminated sample matrix spiked with known amounts of analytes from a source independetn from calibration standard |
used to establish intralaboratory or analyst precision |
¨Performance Evalkuation Sample |
A sample whose composition is unknown to the analyst |
used to test whether the analyst can produce within given performance limitations |
Blind Sample |
A subsample submitted for analysis with a composition and identity known to the submitter but unknown to the analyst |
used to test whether the analyst’s or laboratory proficiency |
Blank Sample |
A clean sample or a sample of matrix processed to measure artifacts in the measurement process |
used to estimate contaminants |
Trip Sample |
A clean sample of matrix that is carried to the sampling site and transported to the laboratory for analysis without being exposed to sampling procedures |
used to estimate contaminants |
Field Blank |
A clean sample carried to the sampling site and exposed to the sampling locations |
used to check for analytical artifacts |
Sampling Equipment Blank |
A clean sample, collected in a sample container with the sample collection device and returned to the laboratory as a sample |
used to check thecleanliness of the devices |