Section 149.48. Quality control requirements for chemical testing.

 

(1)   General requirements .

(a) Laboratories shall establish a quality control program that includes the analysis of appropriate samples, such as method blanks, laboratory control samples, matrix spikes, matrix spike duplicates, replicates, surrogate spikes and analytical protocols, such as detection limit studies and confirmatory techniques. These quality control procedures shall be used to assess:

1. The level of background contamination associated with the preparation and analysis of all samples.

2. The sensitivity of all tests performed.

3. The level of control of an entire analytical system.

4. The bias contributed to sample results by all preparation and analysis steps.

5. The reproducibility of test results.

6. The selectivity of test methods.

(b) At least annually, laboratories shall review and evaluate the acceptability criteria specified in this section for all quality control samples and measures, and update the criteria whenever the performance characteristics of any of these samples and measures change.

(c) Laboratories may not adjust or correct the sample results by the recoveries of associated laboratory control samples, matrix spikes and surrogates, unless a method or project plan approved by the department requires it. Laboratories may not subtract analyte concentrations found in method blanks from sample results unless a method or project plan approved by the department requires it.

(d) Laboratories shall establish procedures for identifying and documenting preparation batches that facilitate determining compliance with the frequencies of quality control samples required by this subchapter.

(2)   Limits of detection and quantitation.

(a) Laboratories shall determine the limit of detection for all tests performed and for all analytes reported except for:

1. Biochemical oxygen demand.

2. Tests for which analyzing a fortified sample is impossible.

3. Titrimetric tests .

4. Gravimetric tests, other than oil and grease as hexane extractable materials.

(b) Laboratories shall determine the limit of detection of an analyte by a protocol established by regulation or as referenced in approved methods of analysis. All sample-processing steps of a test method shall be included in the determination of a limit of detection.

(c) For tests for which this chapter does not require performing a limit of detection, laboratories shall establish estimates of a test's sensitivity based on the intended use of the data for a given application.

(d) Limits of detection shall be determined at least annually unless a laboratory can verify the continued applicability of a previously determined limit of detection by an established and defensible protocol.

(e) Limits of detection shall be determined each time there is a change in a test method or instrumentation that affects the sensitivity of an analysis.

(f) Laboratories shall establish procedures to relate limits of detection to limits of quantitation.

(g) Established limits of quantitation shall be above determined limits of detection.

(3)   Method blank.

(a) Method blanks shall be processed along with and under the same conditions, including all sample preparation steps, as the associated samples in a preparation batch.

(b) Method blanks shall be processed at a frequency of at least one per preparation batch. When samples are analyzed by methods that do not require a preparation step before analysis, a blank, different from a calibration blank, shall be analyzed at the frequency of one per analytical batch.

(c) Whenever a method blank contains analytes of interest above the detection limit of an analysis, the laboratory shall evaluate the nature of the interference and its effect on each sample in a preparation batch.

(d) A sample in a batch shall be reanalyzed or qualified if the concentration of an analyte of interest in the associated method blank exceeds the highest of any of the following values:

1. The limit of detection.

2. Five percent of the regulatory limit for that analyte.

3. Ten percent of the measured concentration in the sample.

(4)   Laboratory control samples.

(a) Unless otherwise exempted by this subsection, a laboratory control sample shall be processed at a frequency of at least one sample per preparation batch, along with and under the same conditions as the associated samples in a preparation batch. These conditions shall include all sample preparation steps, except waste characteristic extractions.

(b) Laboratory control samples for the biochemical oxygen demand and carbonaceous biochemical oxygen demand tests shall be fortified with a mixture of glucose and glutamic acid as specified in approved methods of analysis. These laboratory control samples shall be processed at a frequency of at least one sample per analytical batch for laboratories that analyze more than 20 samples per week. Laboratories that analyze fewer than 20 samples per week shall analyze, at a minimum, one laboratory control sample per week.

(c) Laboratory control samples are not required to be processed for tests for which analyzing a fortified sample is impossible or impractical, or when a laboratory follows par. (e) .

(d) Matrix spikes or certified reference materials may be processed for all reported analytes, at the frequency described in par. (a) , in place of laboratory control samples, if the acceptance criteria for corresponding laboratory control samples are used to evaluate the matrix spikes and the laboratory takes the corrective action required in this subsection when matrix spikes fail established laboratory control sample acceptance criteria.

(e) For analyses of polychlorinated biphenyls, the laboratory shall fortify a laboratory control sample with at least one Aroclor per preparation batch. For other tests that determine analytes with responses that encompass more than one chromatographic peak, as in the case of toxaphene and chlordane, the laboratory may fortify a laboratory control sample with a single multi-peak analyte per preparation batch. The laboratory shall ensure that all multi-peak analytes detectable by a method are fortified in laboratory control samples at least once every year that any of those analytes are reported.

(f) The laboratory shall compute the recovery of each fortified analyte in a laboratory quality control sample. The laboratory shall evaluate the results of laboratory control samples against acceptance criteria published by the department, or when the department has not published acceptance criteria, against:

1. Criteria contained in approved methods of analysis.

2. Laboratory generated acceptance criteria when approved methods of analysis do not contain acceptance criteria.

3. Criteria specified in project quality plans approved by the department.

(g) When laboratory control samples do not meet acceptance criteria, the laboratory shall reprocess or reanalyze all samples associated with the failing laboratory control samples or qualify the results of all samples in the preparation batch.

(h) Laboratories may process and analyze replicate laboratory control samples to establish a measure of the ability of an analytical system, independent of matrix effects, to reproduce results. The laboratory may reprocess or reanalyze all samples, or qualify the results of all samples in a preparation batch, if the relative percent difference of laboratory sample control duplicates exceeds criteria established by the laboratory.

(5)   Quality control standards.

(a) Laboratories that do not use second source standards to verify the accuracy of initial calibrations shall analyze quality control standards as defined in s. NR 149.03 (57) , 3 times per year at evenly spaced intervals for all certified or registered analytes determined by tests amenable to fortification, and for which known quality control samples are commercially available.

(b) Laboratories shall evaluate the results of known quality control samples against the acceptance criteria supplied by the provider. If the results of known quality control samples exceed the acceptance limits issued by a provider, the laboratory shall take corrective action and demonstrate within 30 days, through analysis of another known quality control sample or processed second source standard, the effectiveness of the corrective action taken.

(6)   Matrix spikes and matrix spike duplicates.

(a) Matrix spikes and matrix spike duplicates corresponding to the quality system matrix to which collected samples are assigned shall be processed and analyzed, unless as allowed in sub. (7) (a) , when:

1. Mandated test methods require their analysis and a sufficient volume or amount of sample has been received to permit their analysis.

2. Project plans require their analysis.

3. They are used in place of laboratory control samples to evaluate the level of control of an analytical system.

(b) When required to be analyzed by par. (a) , matrix spikes and matrix spike duplicates shall be:

1. Processed along with and under the same conditions as the associated samples in a preparation batch. These conditions shall include all sample preparation steps, except waste characteristic extractions.

2. Processed and analyzed at a frequency of one per preparation batch of samples consisting of the same quality system matrix or at frequency specified by a project plan or client agreement.

3. Fortified with the analytes specified in approved methods, project plans, client agreements or with all reported analytes, except as allowed in sub. (4) (e) .

4. Fortified with all reported analytes when matrix spikes are used in place of laboratory control samples.

(c) The laboratory shall compute the recovery of each fortified analyte in a matrix spike and matrix spike duplicate, and the relative percent difference or absolute difference of each fortified analyte in a matrix spike and matrix spike duplicate pair. The laboratory shall evaluate the recoveries, and the relative percent difference or absolute range against acceptance criteria published by the department, or when the department has not published criteria, against:

1. Criteria contained in approved methods of analysis.

2. Laboratory generated acceptance criteria when approved methods of analysis do not contain acceptance criteria.

3. Criteria specified in documented and approved project quality plans, or client agreements.

(d) When matrix spikes or matrix spike duplicates do not meet acceptance criteria, the laboratory shall reprocess, reanalyze or qualify the results of the chosen fortified sample in the preparation batch. When the laboratory determines that the failure of matrix spikes or matrix spike duplicates has affected other samples in the same preparation batch, the laboratory shall reprocess or reanalyze the samples, or qualify their results.

(7)   Sample replicates.

(a) Sample replicates may be analyzed in place of matrix spike duplicates when there is a high probability that a replicate pair will contain the analytes of interest at or above the limit of quantitation of an analysis.

(b) Sample replicates corresponding to the quality system matrix to which collected samples are assigned, shall be processed and analyzed when:

1. Mandated test methods require their analysis and a sufficient volume or amount of sample has been collected or received to permit their analysis.

2. Project plans require their analysis.

3. Clients, by agreement with a laboratory, require their analysis.

(c) When required to be analyzed by par. (b) , sample replicates shall be:

1. Processed along with and under the same conditions, including all sample preparation steps, as the associated samples in a preparation batch.

2. Processed and analyzed at a frequency of one per preparation batch of samples consisting of the same quality system matrix or at a frequency specified by a project plan or client agreement.

(d) The laboratory shall compute the relative percent difference or absolute difference of each pair of sample replicates. The laboratory shall evaluate these results against acceptance criteria published by the department, or when the department has not published acceptance criteria, against:

1. Criteria contained in approved methods of analysis.

2. Laboratory generated acceptance criteria when approved methods of analysis do not contain criteria.

3. Criteria specified in documented and approved project quality plans or client agreements.

(e) When sample replicates do not meet acceptance criteria, the laboratory shall reprocess, reanalyze or qualify the results of the chosen sample analyzed in replicate in the preparation batch. When the laboratory determines that the failure of sample replicates has affected other samples in the same preparation batch, the laboratory shall reprocess or reanalyze the samples or qualify their results.

(8)   Surrogate spikes.

(a) Surrogate compounds specified in approved methods of analysis or documented and approved project plans shall be added to all samples in a preparation batch, including method blanks, laboratory control samples, matrix spikes, matrix spike duplicates and replicates.

(b) The laboratory shall compute the recovery of all surrogates added to each sample in a preparation batch. The laboratory shall evaluate these results against acceptance criteria published by the department, or when the department has not published acceptance criteria, against:

1. Criteria contained in approved methods of analysis.

2. Laboratory generated acceptance criteria when approved methods of analysis do not contain criteria.

3. Criteria specified in documented and approved project quality plans or client agreements.

(c) When surrogate recoveries do not meet acceptance criteria, the laboratory shall determine whether the failures are the result of matrix interference. If the failures result from matrix interference, the laboratory shall qualify the results of the affected samples. If the failures cannot be attributed to matrix interference, the laboratory shall reprocess and reanalyze the affected samples or qualify sample results.

(9)   Selectivity.

(a) The laboratory shall establish procedures to confirm the results of organic analytes determined by techniques that, unlike mass spectrometry, do not provide a positive unique identification when:

1. The history of a sample source does not suggest the likely presence of the detected analyte.

2. A client or approved project plan requires it.

(b) The laboratory shall establish procedures and rules for reporting results for samples analyzed by dual column and dual detector systems that declare:

1. Under what conditions a presumptive identification is confirmed.

2. Under what conditions a presumptive identification is reported.

3. The value that will be reported when the dual systems both provide quantitative confirmed results.

(c) The laboratory shall develop and document acceptance criteria, for chromatographic retention time windows, which consider retention time shifts due to routine column maintenance.

(d) The laboratory shall document acceptance criteria for mass spectral tuning.

History: CR 06-005 : cr. Register April 2008 No. 628 , eff. 9-1-08.

Note

Method blanks are not appropriate or required for analysis of pH, alkalinity, conductivity and solids determinations . Microsoft Windows NT 6.1.7601 Service Pack 1 Waste characteristic samples are fortified after the extraction is completed. Microsoft Windows NT 6.1.7601 Service Pack 1 Laboratory control samples need not be analyzed for the following tests: pH, solids determinations, chlorophyll a, color, odor, oil and grease as freon extractable material. Microsoft Windows NT 6.1.7601 Service Pack 1 Analysis of quality control standards is not required for tests, such as pH, which are performed using instruments calibrated by tuning them to conform to a universally accepted scientific law or scale. These tests are also exempt from initial calibration verification with a second source standard. Microsoft Windows NT 6.1.7601 Service Pack 1 Matrix spikes need not be analyzed for the following tests: biochemical oxygen demand, carbonaceous biochemical oxygen demand, pH, solids determinations, alkalinity, acidity, chlorophyll a, color, odor, oil and grease as freon extractable material. Microsoft Windows NT 6.1.7601 Service Pack 1 Waste characteristic samples are fortified after the extraction is completed. Microsoft Windows NT 6.1.7601 Service Pack 1