Quality control/assurance recommended

SMHI uses quality assurance and quality control procedures recommended by ICES/ HELCOM/OSPAR/IOC. 

The use of appropriate reference materials should be a key feature of the quality assurance/quality control structure in any future ocean science project involving chemical measurement. Reference materials use should be explicitly addressed in the project planning stages, proposals, and publications. In the event that appropriate reference materials are not already available, the committee recommends that the proposed project develop a strategy for preparation to assure the ultimate value of measurements made as part of the research. 

Similar to the methods validation protocol, it is recommended to obtain approval signatures from both the director of quality control and quality assurance because of the regulatory criticality of a method transfer exercise. 

Several recommendations arose from the interlaboratory smdy to minimize analytical challenges and to ensure data quality. As discussed above, it is recommended that mass labelled PFCs be employed as internal standards [93, 97]. It should be noted, however, that some electrospray ionization suppression may still occur if these internal standards are used at high concentrations [97]. Matrix effects can also be minimized by employing matrix-matched calibration standards in lieu of solvent-based calibration standards [97]. Unfortunately, matrix-matched standards can be impractical when an appropriate clean matrix cannot be found [94]. Other quality assurance and quality control measures, such as spike and recovery analyses of an analyte added to the sample matrix, repetitive analysis of samples to determine precision and comparison of internal standard quantitation to quantitation via standard additions, are also useful in determining data quality [94]. 

CRMs are an important tool for quality assurance and quality control in analytical laboratories. They are used for verification of accuracy and precision (i.e., reliability of the results of analysis, validation of analytical procedures, establishing measurement traceability, and calibration of measurement equipment). Use of CRMs is recommended by the ISO/IEC 17025 standard and therefore it is obligatory for those who wish to obtain and maintain accreditation of the laboratory. 

To have a real impact on the quality of the laboratory performance the participation in interlaboratory performance studies should be done on a regular basis and should be an integral part of the laboratory quality assurance and quality control system. The common project of lUPAC/AOAC/ISO, leading to a harmonised protocol [3] gives several indications and recommendations on the organisation and evaluation of such interlaboratory studies. 

Standards and standardization play a major role in reliability assurance. Only by using standard methods for product quality control can a product be introduced into the market. Quality standards are very important, especially for food analysis. Recommended standard (or etalon in French) matrices as well as methods are defined in terms of accuracy and precision.246 The European Union has prescribed strict quality standards for laboratories and the methods of analysis to be used in laboratories when carrying out official food quality control. 

Measures should be taken to confirm that designated Manufacturing and Quality Assurance procedures are being followed by staff at ail levels. To this end appropriate Production, Quality Control and (as necessary) Engineering staff should carry-out periodic inspection and evaluation of the Company s own Quality Assurance systems. This should cover production, warehousing and quality control laboratories, and resulting in a formal written report with recommendations for action. Follow-up action should be recorded. 

Method 3810 recommends that a sample be heated to 90°C and 2 mL of headspace gas taken with a gas-tight syringe. The written procedure for this method was published in SW-846 and provided no data on method performance at that time. The publication of a method from a regulatory agency without even a minimum of quality assurance and quality control is inexcusable This method serves as one example of neglected GLP. The importance of GLP was introduced in Chapter 1 and this neglect attests to the fact that little to no interest in static HS techniques existed back in 1986. 

Some difficulties arise when the material requirements, or the material test methods, must be specified for balsa wood because its physical properties are uniquely complex. Structural components typically are fabricated from a multiplicity of laminated strips or planks. These are selected and combined in such a manner that the mechanical properties averaged over the full size component will meet or exceed certain specified values. The quality assurance and quality control (QA/QG) procedures for making sure that this is the case are not simple, however. It will be shown later that conventional test coupons complying with recommended ASTM Standard Methods of Test are likely to exhibit mechanical properties that are far from being representative of the whole laminate. Conventional methods of material testing. 

The laboratory must describe sample preparation and analytical methods in detail or must make reference to Recommended Operating Procedures (ROPs), or Standard Operating procedures (SOPs) or to the validated procedures according to the quahty assur-anoe/quality control (QA/QC) regime of the laboratory. All deviations from the procedures will have to be described in detail. 

The usability of the calibration depends on the type of instrument and can last for a period of up to several days or weeks. All tuning parameters, in particular the adjustment of the ion source, affect the calibration as described above. In particular the analyzer scan speed has a strong impact on the mass calibration with many instruments. Special attention should also be paid to a constant temperature of the ion source. Regular mass calibration using analysis conditions is recommended to comply with the lab internal QA/QC (quality assurance/quality control) procedures. 

To assure the accuracy and comparabihty of the results with other laboratories, an appropriate external quality assessment is necessary. For external quality control, participation in a round robin test is recommended. There are various quality control programs containing cadmium in blood and urine, e.g., the international program of the German External QuaUty Assessment Scheme (E-QUAS), where cadmium analysis can be tested for the concentration range found in occupational and environmental medicine [48], or the external quahty assessment schemes of the Centre of Toxicology in the National Institute of Public Health of Quebec [49]. 

Because of the status of the CAC described above, the work that it has carried out in the area of laboratory quality assurance must be carefully considered. One of the CAC Committees, the Codex Committee on Methods of Analysis and Sampling (CCMAS), has developed criteria for assessing the competence of testing laboratories involved in the official import and export control of foods. These were recommended by the Committee at its 21st Session in March 19979 and adopted by the Codex Alimentarius Commission at its 22nd Session in June 1997 10 they mirror the EU recommendations for laboratory quality standards and methods of analysis. The guidelines provide a framework for the implementation of quality assurance measures to ensure the competence of testing laboratories involved in the import and export control of foods. They are intended to assist countries in then-fair trade in foodstuffs and to protect consumers. 

For the majority of the methods, the necessary quality assurance is provided by a combination of simple and robust sampling techniques with well-described sampling equipment, and the use of synthetic control samples for the chemical analyses. The methods defined in EMEP4 are harmonized whenever possible with recommendations in other networks such as WMO/GAW5 and standardization organizations such as the European Committee for Standardization (CEN). 

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