Section 144-263-11 - QUALITY CONTROL CRITERIAA.Quality control criteria for chemistry1. Scopea. This section applies to laboratories performing testing under the inorganic chemistry, metals, volatile organic compounds and other organic compounds test categories unless otherwise indicated.b. All requirements in this Section must be incorporated into the laboratory's procedures, unless otherwise directed by the approved method. The quality control requirements specified by the laboratory's standard operating procedures must be followed.c. All quality control measures must be assessed and evaluated on an ongoing basis and quality control acceptance criteria must be used to determine the validity of the data.2. Method blanks a. A method blank must be processed along with and under the same conditions as the associated samples to include all steps of the analytical procedure.b. The method blank must be analyzed at a minimum of one per batch.c. Procedures must be in place to determine whether a method blank is contaminated. Any affected samples associated with a contaminated method blank must be reprocessed for analysis or the results must be reported with appropriate data qualifying codes.d. Each contaminated method blank must be critically evaluated as to the nature of the interference and the effect on the analysis of each sample within the batch. The source of contamination must be investigated, and measures taken to minimize or eliminate the problem. Affected samples must be reprocessed or data must be appropriately qualified if: (i) The concentration of a target analyte in the blank is at or above the reporting limit as established by the test method or by regulation and is greater than one-tenth of the amount measured in any sample; or(ii) The blank contamination otherwise affects the sample results according to test method requirements or the individual project data quality objectives.3. Laboratory control sample (LCS)a. An LCS must be used to evaluate the performance of the total analytical system, including all preparation and analysis steps. Results of the LCS must be compared to established criteria and, if found to be outside of established criteria, must indicate that the analytical system is "out of control." Any affected samples associated with an out of control LCS must be reprocessed for reanalysis or the results must be reported with appropriate data qualifying codes.b. An LCS must be analyzed at a minimum of one per preparation batch, except for:(i) Analytes for which no spiking solutions are available; or(ii) When the method specifically states that the LCS is not necessary.c. All analyte concentrations must be within the calibration range of the instrument calibration. The components to be spiked must be as specified by the permit, program or rule requirement. In the absence of permit, program, rule or method requirements, the laboratory must spike as follows:(i) For those components that interfere with an accurate assessment, such as spiking simultaneously with technical chlordane, toxaphene and PCBs, the spike must be chosen that represents the chemistries and elution patterns of the components to be reported.(ii) The number of analytes selected is dependent on the number of analytes reported. The analytes selected for the spiking solution must be representative of all analytes reported. The following criteria must be used for determining the minimum number of analytes to be spiked:(1) For methods that include one to ten analytes, spike all components.(2) For methods that include 11 to 20 analytes, spike at least ten components or 80 percent of the analytes, whichever is greater.(3) For methods with more than 20 analytes, spike at least 16 components.d. The results of the analytes included in the LCS are calculated in percent recovery or a measure that allows comparison to established acceptance criteria. The laboratory must document the calculation. The individual LCS is compared to the acceptance criteria as published in the approved method or as specified in client-specified assessment criteria within a permit, program or rule requirement. When there are no established criteria, the laboratory must determine its own criteria and document the method used to establish the limits or utilize client-specified assessment criteria within a permit, program or rule requirement.e. An LCS that is determined to be within the criteria effectively establishes that the analytical system is in control and validates system performance for the samples in the associated batch. Samples analyzed along with an LCS determined to be "out of control" must be considered suspect. The samples must be reprocessed and reanalyzed or the data must be reported with appropriate data qualifying codes.4. Matrix spike and matrix spike duplicatesa. The frequency of the analysis of matrix spikes and matrix spike duplicates must be determined as part of a systematic planning process or as specified by the required approved method, when applicable. Where no requirement is stated, the laboratory must prepare and analyze at least one matrix spike and one matrix spike duplicate with each batch, unless the lab has not been provided a sufficient sample amount. The matrix spikes must be prepared from samples contained in the batch.b. For a matrix spike, the components to be spiked must be as specified by the approved method or permit, program or rule requirement. In the absence of specified spiking components, the laboratory may follow client instructions and then must document its criteria for quality control. In the absence of client instruction, the laboratory must spike as follows: (i) For those components that interfere with an accurate assessment, such as spiking simultaneously with technical chlordane, toxaphene and PCBs, the spike must be chosen that represents the chemistries and elution patterns of the components to be reported.(ii) The number of analytes selected is dependent on the number of analytes reported. The analytes selected for the spiking solution must be representative of all analytes reported. The following criteria must be used for determining the minimum number of analytes to be spiked:(1) For methods that include one to ten analytes, spike all components.(2) For methods that include 11 to 20 analytes, spike at least ten components or 80 percent of the analytes, whichever is greater.(3) For methods with more than 20 analytes, spike at least 16 components.c. The results from matrix spikes and matrix spike duplicates must be expressed as percent recovery, relative percent difference, absolute difference or other appropriate measure. Results of matrix spikes and matrix spike duplicates must be compared to the acceptance criteria as published in the approved method or as specified in client-specified assessment criteria within a permit, program or rule requirement. When there are no established criteria, the laboratory must determine its own criteria and document the procedure used to establish the limits or utilize client-specified assessment criteria within a permit, program or rule requirement.5. Surrogate spikesa. This sub-section applies to the analysis of organic compounds.b. Except when the matrix precludes their use or when not available, surrogate compounds must be added to all samples, standards and blanks for all appropriate test methods before sample preparation or extraction.c. Surrogate compounds must be chosen to represent the various chemistries of the analytes in the method. When specified, the surrogates mandated in the method must be used.d. The results from surrogate spikes must be expressed as percent recovery. Results of surrogate spikes must be compared to the acceptance criteria as published in the approved method. When there are no established criteria, the laboratory must determine its own criteria and document the method used to establish the limits or utilize client-specified assessment criteria within a permit, program or rule.6. Internal standardsa. This sub-section applies to the analysis of organic compounds.b. When internal standards are recommended or required by the test method, such as mass spectrometry techniques, a laboratory must add the internal standards to all samples, standards, blanks and QC samples before analysis.c. When specified in the test method, a laboratory must use the internal standards mandated in the test method. If internal standards are not recommended in the method, then the analyst must select one or more internal standards that are similar in analytical behavior to the compounds of interest and not expected to be found in the samples otherwise.d. A laboratory must monitor and document the results from analysis of internal standards.e. Results of internal standards must be compared to the acceptance criteria as published in the approved method. When there are no established criteria, the laboratory must determine its own criteria and document the procedure used to establish the limits or utilize client-specified assessment criteria within a permit, program or rule requirement.7. Method detection limits (MDL)a. Each laboratory must experimentally determine the MDL for analysis of each analyte, if applicable, for each matrix in which the laboratory is accredited.b. The laboratory must document its procedure for determining the MDL.c. MDL procedures must be conducted as follows:(i) Drinking Water Program methods: The laboratory must use the procedure for determining the MDL that is described in the analytical method being used. If the analytical method does not include a procedure for the determination of MDLs, then the laboratory must determine the MDL using the procedure described in 40 CFR Part 136 , Appendix B, updated in the Annual Edition of July 1, 2022.(ii) Wastewater Program methods: The laboratory must use the procedure for determining the MDL using the procedure described in 40 CFR Part 136 , Appendix B, updated in the Annual Edition of July 1, 2022.d. Calculations and supporting documentation used in determining limits must be available for inspection.e. MDLs must be expressed in appropriate method reporting units.f. The laboratory must achieve the MDLs required by the applicable regulations or program.g. Sample preparation and analysis for the MDL calculation must be made over a period of at least three days.h. MDLs must be determined as part of a laboratory's initial demonstration of capability to perform an analysis, when there is a change in the test method that may affect how the test is performed, when a change in instrumentation occurs that affects the sensitivity of the analysis, and as required by an analytical method.i. MDLs must be determined using analysts and instruments that are representative of those used in the performance of analyses.j. The laboratory must verify its capability to analyze reporting level standards on an ongoing basis through the analysis of reporting level verification standards that utilize all preparation and analytical steps as required for samples.k. The accreditation officer must not require a detection limit study for any component for which spiking solutions or quality control samples are not available.8. Reporting limits (RL) a. The laboratory must determine the minimum RL for analysis of each analyte for each matrix in which the laboratory is accredited. The laboratory must document the procedure used to determine the minimum reporting level. The laboratory must verify the minimum reporting level on an ongoing basis.b. The RLs must be greater than the MDLs.c. A laboratory must verify the RL each time the instrument is calibrated or monthly at a minimum. The laboratory must analyze a verification standard prepared at a concentration equal to or below the RL, prepared using all the steps of the procedure. The percent recovery of the standard must fall within plus or minus 40 percent of the true value, unless otherwise stated in the method.d. If the percent recovery of the RL verification standard is outside the acceptance criteria, a laboratory must elevate the reporting limit for the associated samples to the concentration of the lowest point, above the zero blank, that meets the criteria in Section 8. The laboratory must report all samples analyzed after the failed RL check using the elevated RL until a new calibration curve and RL verification standard meet the acceptance criteria.9. Selectivity a. This sub-Section applies to organic compounds.b. Absolute retention time and relative retention time aid in identifying components in chromatographic analyses and evaluating the effectiveness of a chromatographic medium to separate constituents. A laboratory must develop and document acceptance criteria for retention time windows if the acceptance criteria are not specified in the approved method.c. A confirmation must be performed to verify the compound identification when positive results are detected in drinking water. The confirmations must be performed on organic tests, such as pesticides, herbicides or acid-extractable compounds or when recommended by the analytical test method, except when the analysis involves the use of a mass spectrometer or Fourier transform infrared spectrometer (FTIR). All confirmations must be documented.d. A confirmation must be performed to verify the compound identification when positive results are detected in a sample from a location that has not been previously tested. The confirmations must be performed on organic tests, such as pesticides, herbicides or acid-extractable compounds, or when recommended by the analytical test method, except when the analysis involves the use of a mass spectrometer or FTIR. A confirmation is not required on positive results for samples analyzed for diesel range organics and gasoline range organics, Extractable Petroleum Hydrocarbons (EPH), Volatile Petroleum Hydrocarbons (VPH) or Total Extractable Petroleum Hydrocarbons (TEPH) under the Underground Storage Tank Program. All confirmations must be documented.e. A laboratory must document acceptance criteria for mass spectral tuning. The laboratory must ensure that the tuning criteria meet the specifications in the approved method or as established by the client, whichever is more stringent.10. Manual integrations a. If the integrations are not calculated exclusively by the equipment's software, a laboratory must document acceptable use of manual integrations and must have in place a system for review of manual integrations performed to verify adherence to the policies and procedures of the laboratory.11. Consistent test conditionsa. A laboratory must ensure that the test instruments consistently operate within the specifications required of the application for which the equipment is used.b. A laboratory must ensure that glass and plastic containers are cleaned so that they meet the sensitivity of the test method. Any cleaning and storage procedures that are not specified by the test method must be documented in laboratory records and the laboratory SOPs manual.B.Quality control criteria for bacteriology1. Scope This Section applies to laboratories performing tests under the bacteriological test category unless otherwise indicated. All requirements in this Section must be incorporated into the laboratory's procedures unless otherwise directed by the approved method. The QC requirements specified by the laboratory's SOPs must be followed. All QC measures must be assessed and evaluated on an ongoing basis and QC acceptance criteria must be used to determine the validity of the data.2. Sterility and Autofluorescence Checks a. Each lot of pre-prepared, ready-to-use media, including chromofluorogenic reagent and each lot of media prepared in the laboratory must be checked for sterility. Chromofluorogenic media must also be checked for autofluorescence. The media check must be run using a container and water that has passed a sterility check. The analysis must be done before first use of each lot of media.b. For filtration technique: (i) A laboratory must conduct one beginning and one ending sterility check for each filtration unit used in a filtration series. The filtration series may include single or multiple filtration units that have been sterilized before beginning the series.(ii) For pre-sterilized, single-use funnels purchased, a sterility check must be performed on one funnel per lot before use.(iii) The filtration series is considered ended when more than 30 minutes elapse between successive filtrations.(iv) During a filtration series, filter funnels must be rinsed with three 20 to 30 milliliter portions of sterile rinse water after each sample filtration.(v) Laboratories must insert a sterility blank after every ten samples per filtration unit or sanitize filtration units by ultraviolet light after each sample filtration.c. For pour-plate technique, a sterility check of the media must be made by pouring, at a minimum, one uninoculated plate for each lot of pre-prepared, ready-to-use media and one for each lot of media prepared in the laboratory.d. Sterility checks on sample containers and Quanti-Trays® must be performed on at least one container for each lot of purchased, pre-sterilized containers. For containers sterilized in the laboratory, a sterility check must be performed on one container per sterilized batch, using nonselective growth media. Sample containers used for chromofluorogenic methods must also be checked for autofluorescence. The analysis must be done before first use.e. A sterility check must be performed on each batch of dilution water prepared in the laboratory and on each batch of pre-prepared, ready-to-use dilution water using nonselective growth media. The analysis must be done before first use.f. At least one filter from each new lot of membrane filters must be checked for sterility by filtering 20 to 30 milliliters of sterile dilution water through the filter and testing for growth. The analysis must be done before first use.3. Positive controls Each pre-prepared, ready-to-use lot of media, including chromofluorogenic reagent, and each lot of media prepared in the laboratory must be tested with at least one pure culture of a microorganism known to elicit a positive reaction. This must be done before first use of each lot of media.
4. Negative controls Each pre-prepared, ready-to-use lot of selective media, including chromofluorogenic reagent and each lot of selective media prepared in the laboratory must be analyzed with one or more known negative culture controls (e.g., non-target microorganisms) that should not grow on the test media, as appropriate to the method. This analysis must be done before first use of each lot of media.
5. Test variability For test methods that specify colony counts, such as methods using membrane filters or plated media, duplicate counts must be performed and documented monthly on at least one positive sample for each month that the test is performed. With respect to this test for variability, if the laboratory has two or more analysts, each analyst must count typical colonies on the same plate and counts must be within a ten-percent difference between analysts to be acceptable. In a laboratory with only one bacteriology analyst, the same plate must be counted twice by the analyst, with no more than a five-percent difference between the counts.
6. Method evaluation A laboratory must demonstrate proficiency with the test method before first use, by comparison to a method already approved for use in the laboratory, by analyzing a minimum of ten spiked samples with a matrix representative of those normally submitted to the laboratory or by analyzing and passing one proficiency test series provided by an approved proficiency sample provider. The laboratory must maintain documentation of the proficiency demonstration, as long as the method is in use and for at least five years after the date of last use.
7. Test performance To ensure that analytical results are accurate, those laboratories using commercially prepared media with manufacturer shelf-lives of greater than 90 days must run positive and negative controls each quarter, in addition to running these controls and sterility checks on each new lot of media.
8. Quality of standards, reagents and media a. Culture media may be prepared from commercial dehydrated powders or may be purchased ready-to-use, unless otherwise indicated in the approved method. Media may be prepared by the laboratory from basic ingredients when commercial media are not available or when it can be demonstrated that commercial media do not provide adequate results. Media prepared by the laboratory from basic ingredients must be tested for performance, such as for selectivity, sensitivity, sterility, growth promotion and growth inhibition, before first use. Detailed testing criteria information must be defined in the laboratory's SOPs manual or QA manual.b. Reagents, commercial dehydrated powders and media must be used within the shelf life of the product. The specifications of the reagent, powder or media must be documented according to the laboratory's QA manual.c. Distilled, deionized or reverse-osmosis produced water that is free from bactericidal and inhibitory substances must be used in the preparation of media, solutions and buffers. The quality of the water must meet the requirements as listed in Section 8.d. Media, solutions and reagents must be prepared, used and stored according to a documented procedure following the manufacturer's instructions or the test method. Documentation for media prepared in the laboratory must include the: (ii) Preparer's initials;(iii) Type and amount of media prepared;(iv) Manufacturer and lot number;(v) Final pH of the media after sterilization; ande. Documentation for media purchased pre-prepared and ready-to-use must include the:(iii) Type and amount of media received;(v) Expiration date of the media; and(vi) Verification of the pH of the liquid.9. Selectivity a. To ensure identity and traceability, reference cultures used for positive and negative controls must be obtained from a recognized national organization.b. Microorganisms may be single-use preparations or cultures maintained by documented procedures that demonstrate the continued purity and viability of the organism.c. Reference cultures may be revived, if freeze-dried or transferred from slants and sub-cultured once to provide reference stocks. The reference stocks must be preserved by a technique that maintains the characteristics of the strains. Reference stocks must be used to prepare working stocks for routine work. If reference stocks have been thawed, they must not be refrozen and reused.d. Working stocks must not be cultured sequentially more than five times and must not be sub-cultured to replace reference stocks.10. Temperature measuring devicesa. Temperature measuring devices such as liquid-in-glass thermometers, thermocouples and platinum resistance thermometers used in incubators, autoclaves and other equipment must be of the appropriate quality to meet specifications in the test method.b. The temperature measuring devices must be graduated in 0.5°C increments (or 0.2°C increments for tests which are incubated at 44.5°C) or less, except as noted for hot air ovens and refrigerators. These devices must be calibrated against thermometers from an accredited third party or a National Metrology Institute (e.g., NIST), traceable to the SI, International System of Units. All measurements must be recorded.11. Autoclaves a. The performance of each autoclave must be evaluated initially by establishing its functional properties and performance (e.g., heat distribution characteristics with respect to typical uses). Autoclaves must meet specified temperature tolerances. Pressure cookers must not be used for sterilization of growth media.b. Demonstration of sterilization temperature must be provided by use of a continuous temperature recording device or by use of a maximum registering thermometer with every cycle. Appropriate biological indicators must be used once per month to determine effective sterilization. Temperature-sensitive tape must be used with the contents of each autoclave run to indicate that the autoclave contents have been processed.c. Records of autoclave operations must be maintained for every cycle. Records must include: date, contents, maximum temperature reached, pressure, time in sterilization mode, total run time (which may be recorded as time in and time out) and operator's initials.d. Autoclave maintenance, either internally or by service contract, must be performed annually or must include a pressure check and calibration of the temperature device. Records of the maintenance must be maintained in equipment logs.e. The autoclave's mechanical timing device must be checked quarterly against a stopwatch and the actual time elapsed must be documented.12. Ultraviolet instrumentsa. Ultraviolet (UV) instruments used for sterilization must be tested quarterly for effectiveness with an appropriate UV light meter or by plate counts on agar spread plates.b. Bulbs must be replaced if output is less than 70 percent of original for light tests or if count reduction is less than 99 percent for a plate containing 200 to 300 organisms.13. Incubators, water baths and ovensa. The stability and uniformity of temperature distribution and the time required after test sample addition to reestablish equilibrium conditions in incubators and water baths must be documented. Calibration-corrected temperature of incubators and water baths must be documented twice daily, at least four hours apart, on each day of use.b. Ovens used for sterilization must be checked for sterilization effectiveness monthly with appropriate biological indicators. Records must be maintained for each cycle and include the date, cycle time, temperature, contents and analyst's initials.14. Labware, glassware and plasticwarea. A laboratory must have a documented procedure for washing labware, if applicable. Detergents designed for laboratory use must be used.b. Glassware must be made of borosilicate or other noncorrosive material, free of chips and cracks and must have readable measurement marks.c. Labware that is washed and reused must be tested for possible presence of residues that may inhibit or promote growth of microorganisms by performing the inhibitory residue test annually and each time the laboratory changes the lot of detergent or washing procedures.d. At a minimum, one piece of washed labware must be tested daily, each day of washing, for possible acid or alkaline residue. Labware must be tested with a suitable pH indicator (e.g., Bromothymol blue). Records of tests must be documented.15. Quanti-Tray® sealer When the Quanti-Tray® or Quanti-Tray® 2000 test is utilized, the sealer must be checked monthly by adding a dye (e.g., Bromocresol purple) to the water. If the dye is observed outside of the wells, maintenance must be performed, or another sealer utilized.C.Quality control criteria for radiochemistry1. Scope a. This Section applies to laboratories performing radiochemistry testing on environmental samples. All requirements in this Section must be incorporated into the laboratory's SOPs unless otherwise directed by the approved method.b. The quality control requirements specified by the laboratory's SOPs must be followed. All quality control measures must be assessed and evaluated on an ongoing basis and quality control acceptance criteria must be used to determine the validity of the data.2. Method blanks a. A laboratory must analyze at least one method blank per batch. The method blank result must be evaluated according to the acceptance criteria in the laboratory's standard operating procedures.b. When the method blank acceptance criteria are not met, a laboratory must take corrective action. The occurrence of a failed method blank and the actions taken must be noted in the laboratory report.c. In the case of gamma spectrometry, where the sample matrix is simply aliquoted into a calibrated counting geometry, the method blank must be of similar counting geometry that is empty or filled to similar volume with ASTM Type II water to partially simulate gamma attenuation due to the sample matrix.d. A laboratory must not subtract results of method blank analysis from the sample results in the associated batch, unless permitted by the approved method. This requirement does not preclude the application of any correction factor, such as instrument background, analyte presence in tracer, reagent impurities, peak overlap or calibration blank, to all analyzed samples, both program- or project-submitted and internal QC samples. The correction factors must not depend on the required method blank result in the associated analytical batch.e. The method blank sample must be prepared with similar aliquot size to that of the routine samples for analysis whenever possible.3. Laboratory control samplea. Laboratory control samples must be performed at a frequency of one per batch. The results of the analysis must be one of the QC measures to be used to assess the batch.b. The laboratory control sample result must be assessed against the specific acceptance criteria specified in the laboratory SOPs. When the specified laboratory control sample acceptance criteria are not met, the specified corrective action and contingencies must be followed.c. The occurrence of a failed laboratory control sample acceptance criterion and the actions taken must be noted in the laboratory report.d. The activity of the laboratory control sample must be:(i) Two to ten times the MDL; or(ii) At a level comparable to that of routine samples, if the sample activities are expected to exceed ten times the MDL.e. The laboratory standards used to prepare the laboratory control sample must be from a source independent of the laboratory standards used for instrument calibration, if available.f. The laboratory control sample must be prepared by adding a known activity of target analyte. When a radiochemical method, other than gamma spectroscopy, has more than one reportable analyte isotope, such as Plutonium, Pu-238 and Pu-239, using alpha spectrometry, only one of the analyte isotopes need be included in the laboratory control sample. When more than one analyte isotope is added to the laboratory control sample, each isotope must be assessed against the specified acceptance criteria.4. Matrix spikes a. Matrix spikes must be performed at a frequency of one per batch for those methods that do not utilize an internal standard or carrier, for which there is a chemical separation process and when there is sufficient sample to do so.b. Gross alpha, gross beta and tritium require matrix spikes for aqueous samples. The result of the analysis must be one of the QC measures used to assess sample acceptability. The matrix spike result must be assessed against the specific acceptance criteria specified in the laboratory SOPs.c. When the specified matrix spike acceptance criterion is not met, the corrective actions specified in the laboratory's SOPs must be followed. The occurrence of a failed matrix spike acceptance criterion and the actions taken must be noted in the laboratory report. The lack of sufficient sample aliquot size to perform a matrix spike must also be noted in the laboratory report.d. The activity of the analytes in the matrix spike must be greater than 10 times the MDL.e. The laboratory standards used to prepare the matrix spike must be from a source independent of the laboratory standards used for instrument calibration, if available.f. The matrix spike must be prepared by adding a known activity of target analyte. When a radiochemical method, other than gamma spectroscopy, has more than one reportable analyte isotope, such as Plutonium, Pu 238 and Pu 239, using alpha spectrometry, only one of the analyte isotopes needs to be included in the matrix spike sample. When more than one analyte isotope is added to the matrix spike, each isotope must be assessed against the specified acceptance criteria.g. When gamma spectrometry is used to identify and quantitate more than one analyte isotope, the laboratory control sample and matrix spike must contain isotopes that represent the low (Americium-241), medium (Cesium-137) and high (Cobalt-60) energy range of the analyzed gamma spectra. As indicated by these examples, the isotopes need not exactly bracket the calibrated energy range or the range over which isotopes are identified and quantitated.h. The matrix spike sample must be prepared with similar aliquot size to that of the routine samples of analyses.5. Tracera. For those approved methods that allow or require the use of a tracer (e.g., internal standard), each sample result must have an associated tracer recovery calculated and reported. The tracer recovery for each sample result must be one of the QC measures used to assess the associated sample result acceptance.b. The tracer recovery must be assessed against the specific acceptance criteria specified in the laboratory SOPs. When the specified tracer recovery acceptance criteria are not met, corrective actions specified in the laboratory's SOPs must be followed. The occurrence of a failed tracer recovery and the corrective actions taken must be noted in the laboratory report.6. Carrier a. For those approved methods that allow or require the use of a carrier, each sample must have an associated carrier recovery calculated and reported. The carrier recovery for each sample must be one of the QC measures used to assess the associated sample result acceptance.b. The carrier recovery must be assessed against the specific acceptance criteria specified in the laboratory SOPs. When the specified carrier recovery acceptance criteria are not met, the corrective actions specified in the laboratory's QA manual must be followed. The occurrence of failed carrier recovery acceptance criteria and the actions taken must be noted in the laboratory report.7. Analytical variability; reproducibility for radiochemistry testinga. A laboratory must analyze replicate samples at least once per batch when there is sufficient sample to do so. The results of the analysis must be one of the QC measures used to assess sample results acceptance. The replicate result must be assessed against the specific acceptance criteria specified in the laboratory's SOPs.b. When the specified replicate acceptance criteria are not met, the corrective actions specified in the laboratory's SOPs must be followed. The occurrence of failed replicate acceptance criteria and the actions taken must be noted in the laboratory test results.c. If sample concentrations are expected to contain analytes of interest below three times the detection limit, a laboratory may substitute replicate laboratory control samples or replicate matrix spiked samples for replicate samples in above. The replicate result must be assessed against the specific acceptance criteria specified in the laboratory's SOPs. When the specified replicate acceptance criteria are not met, the corrective actions specified in the laboratory's SOPs must be followed. The occurrence of failed replicate acceptance criteria and the actions taken must be noted in the laboratory test results.8. Instrument calibration a. Radiochemistry analytical instruments must be calibrated prior to first use in sample analysis.b. Calibration must be verified when: (i) The instrument is serviced;(ii) The instrument is moved; and(iii) The instrument settings have been changed.c. The standards used for calibration must have the same general characteristics (e.g., geometry, homogeneity and density) as the associated samples.d. The calibration must be described in the laboratory's SOPs.9. Continuing calibration verificationa. Calibration verification checks must be performed using appropriate check standards and monitored with control charts or tolerance charts to ensure that the instrument is operating properly and that the calibration has not changed.b. The same check standards used in the preparation of the tolerance chart or control chart at the time of calibration must be used in the calibration verification of the instrument.c. The check standards must provide adequate counting statistics for a relatively short count time. The sources must be sealed or encapsulated to prevent leakage and contamination of the instrument and laboratory personnel.d. For alpha and gamma spectroscopy systems, the instrument calibration verification must include checks on the counting efficiency and the relationship between channel number and alpha or gamma ray energy.e. For gamma spectroscopy systems, the calibration verification checks for efficiency and energy must be performed at least weekly along with performance checks on peak resolution.f. For alpha spectroscopy systems, the calibration verification check for energy must be performed at least weekly and the performance check for counting efficiency must be performed at least monthly for each day the instrument is used for sample analysis.g. For gas-proportional and scintillation counters, the calibration verification check for counting efficiency must be performed each day of use.10. Background radiation measurement a. Background radiation measurements must be performed on a regular basis and monitored using control charts or tolerance charts to ensure that a laboratory maintains its capability to meet required data quality objectives.b. Background radiation measurement values must be subtracted from the total measured activity in the determination of the sample activity.c. For gamma spectroscopy systems, background radiation measurements must be performed at least monthly.d. For alpha spectroscopy systems, background radiation measurements must be performed at least monthly.e. For gas-proportional counters, background radiation measurements must be performed at least weekly.f. For scintillation counters, background radiation measurements must be performed each day of use.11. Instrument contamination monitoring A laboratory must have a written procedure for monitoring radiation measurement instrumentation for radioactive contamination. The procedure must indicate the frequency of the monitoring and must indicate criteria that initiate corrective action.
12. Method detection limits a. Detection limits must be determined before sample analysis and must be redetermined each time there is a significant change in the test method or instrument type.b. The procedures employed must be documented and consistent with published references.13. Quality of standards and reagents a. The QA manual must describe the procurement, use and storage of radioisotope standards.b. Reference standards that are used in a radiochemical laboratory must be obtained from an accredited third party or a National Metrology Institute (e.g., NIST) and be traceable to the SI, International System of Units.c. Reference standards must be accompanied with a certificate of calibration that describes traceability to the SI, International System of Units, from an accredited third party or a National Metrology Institute (e.g., NIST) when appropriate.d. Laboratories must consult with the supplier if the laboratory's assessment of the activity of the reference traceable standard indicates a noticeable deviation from the certified value. The laboratory must not use a value other than the decay-corrected certified value.e. All reagents used must be of analytical reagent grade or better.10-144 C.M.R. ch. 263, § 11