Laserfiche WebLink
z <br /> BROWN AND CALDWELL ANALYTICAL _LABORATORIES <br /> BATCH QC REPORT <br /> Definitions and Terms <br /> Aecuracv: The ability of a procedure to determine the "true" concentration of an <br /> analyte. <br /> Batch: A group of samples analyzed sequcntially using the same calibration curve, <br /> reagents, and instrument_ <br /> Laborato y Control .Laboratory reagent water spiked with known compounds and subjected <br /> Standard (LCS): to the same procedures as thes�.,.pl 1';:e LCS thus indicates the accuracy <br /> of the analytical method and, because it is prepared from a different source <br /> than the standard used to calibrate the instrument, it also serves to double- <br /> check the calibration. <br /> LC Result: Laboratory result of an LCS analysis. <br /> LT Result: Expected result, or true value, of the LCS analysis. <br /> Matrix QC: Quality control tests performed on actual client samples. For most inorganic <br /> analyses, the laboratory uses a pair of duplicate samples and a spiked <br /> sample. For most organic analyses, the laboratory uses a pair of spiked <br /> I samples (duplicate spikes). 3 <br /> Percent Recovery: The percentage of analyte recovered: <br /> For LCS, the percent recovery calculation is <br /> LC _ LTx100. <br /> For spike recoveries, the percent recovery calculation is <br /> (S Bar- Sample Concentration x 100 <br /> Spike Amount <br /> Precision: The reproducibility of a procedure demonstrated by the agreement between <br /> analyses performed on either duplicates of the same sample or a pair of <br /> duplicate spikes. <br /> R 1, R2 Result: Result of the analysis of replicate aliquots of a sample,with R 1 indicating <br /> the fust analysis of the sample and R2 its corresponding duplicate; used to <br /> determine precision. <br /> t Relative Percent Calculated using one of the following: <br /> Difference (RPD): <br /> (P, -R2X 100 (Sl -S21x-_100 <br /> (RI + R2) - 2 .(S1 + S2) - 2 <br /> S Bar Result The average of spike analysis results. <br /> # S l, S2 Result: Result of the analysis of replicate spiked aliquots,with S 1 indicating one <br /> spike of the sample and S2 the second spike; used to determine precision <br /> �--� and accuracy. <br /> True value: The theoretical, or expected,result of a spike:sample analysis. <br />