Laserfiche WebLink
a . If the failure is reported to be due to sample matrix interference , the laboratory shall document the <br /> process by which this conclusion is determined . <br /> 6 . Evaluation of Laboratory Duplicate/Replicate Samples — All replicate samples (sample duplicates , <br /> matrix spike duplicates , LCS duplicates or other replicates ) must be evaluated for a precision criterion <br /> not to exceed 20 % RPD . This criterion shall be listed in the planning document . <br /> a . In the event that laboratory replicate agreement is not observed , the laboratory must investigate <br /> the poor precision and report the results with appropriate qualifiers and/or comments . <br /> 7 . Instrument Calibration — In addition to calibration procedures specified in the analytical methods listed <br /> in the planning document, the GRANTEE shall ensure that the following requirements are met : <br /> a . All sample results shall be chronologically bracketed between acceptable calibration verifications . <br /> b . Initial Calibration Requirements <br /> ( i ) The minimum number of calibration standards required to calibrate each instrument used for <br /> the contracted analyses shall conform to the analytical method approved in the planning <br /> document . If the minimum number of calibration standards is not specified in the method , the <br /> number must be specified in the planning document and shall be consistent with the NELAC <br /> Chapter 5 standards . <br /> ( ii ) Unless otherwise specified by the method , all sample results shall be based on the initial <br /> calibration curve responses . <br /> ( iii ) If linear regressions are used , the correlation coefficient shall be equal to or greater than <br /> 0 . 995 for all regressions . <br /> ( iv) Immediately after performing an initial calibration , the accuracy of the calibration shall be <br /> verified using a second source . A second source may be a standard , a Standard Reference <br /> Material (SRM ) , or other sample type with a verified concentration such as a QC Check <br /> Sample . Standards must have been prepared from a different lot or vendor. <br /> (v) The acceptance criteria for second -source verifications shall be specified in the planning <br /> document . <br /> (vi ) Sample analysis cannot proceed if an initial calibration is unacceptable . <br /> c . Continuing Calibration Requirements : <br /> ( i ) When an initial calibration is not performed on the day of analysis , a continuing calibration <br /> standard shall be analyzed , evaluated and determined to be acceptable prior to analyzing <br /> samples . <br /> ( ii ) A continuing calibration standard shall be analyzed and evaluated at the end of the analytical <br /> run . <br /> ( iii ) The acceptance criteria for continuing calibration verifications shall be specified in the <br /> planning document. <br /> ( iv) For each analytical run , the analytical sensitivity must be evaluated using a continuing <br /> calibration standard prepared at the Agreement-specified PQL . The analyzed value of this <br /> standard must be within 70 % — 130 % of the expected value . If this PQL check fails , the blank <br /> and associated sample results must be reported as "estimated" per Chapter 62- 160 , F . A. C . <br /> unless the affected results are at least 10 times the absolute value of the observed bias of the <br /> PQL check . <br /> (v) If a continuing calibration verification fails , samples not chronologically bracketed by <br /> acceptable calibration verifications must be reanalyzed or appropriately qualified . <br /> d . Sample results below the Agreement-specified PQL and above the highest calibration standard <br /> shall be appropriately qualified . <br /> 8 . Quality Control Blanks <br /> a . If a Contracted analyte is detected in any analytical QC blank , the sample results that <br /> are <br /> associated with the blank must be reported with the appropriate qualifier from Chapter 62- 160 , <br /> F .A. C . , unless the affected sample concentrations are at least 10 times higher than the calculated <br /> QC blank concentration . <br /> b . Sample results must be chronologically bracketed with acceptable beginning and ending <br /> analytical QC blanks . <br /> C . If a Contracted analyte is detected in the field blank , equipment blank or trip blank , the result must <br /> be confirmed by reanalyzing a new aliquot of the blank unless the sample concentration results <br /> Revised 3/05 <br /> DEP Agreement No . GO 143 , Attachment H, Page 9 of 11 <br />