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National traceability network for chemical analytics

Not only are chemical analyses extremely numerous and manifold but they also are significant for society and commerce. To provide these measurements with a joint and reliable framework, the PTB has set up a traceability system for chemical analytics, together with the BAM (Bundesanstalt für Materialforschung und -prüfung, Federal Institute for Materials Testing and Research), the UBA (Umweltbundesamt, Federal Environment Office) and the DGKC (Deutsche Gesellschaft für klinische Chemie, German Society for Clinical Chemistry). This national network increasingly ensures the traceability of the measurement results to the International System of units (SI), thus adding to their credibility and acceptance, preventing expensive multiple measurements in many areas (such as medicine) and improving the prerequisites for unhindered worldwide trade and economic competition.

The partners in the national network intended to ensure the metrological traceability of chemical measurements in Germany. The arrows illustrate contractual relations between the individual partners.

In chemical analytics, an increasing number of customers, accreditation centres and authorities therefore require the statement of measurement uncertainties and that the measurement results being traceable to acknowledged reference points. This is also reflected by the application of the worldwide accepted standard ISO/IEC 17025 “General Requirements for Calibration and Test Laboratories.” In chemistry a metrological traceability system is already available in partial areas, e.g. in clinical chemistry, in certain fields of electrochemistry (pH-value, electrolytic conductivity) and in gas analysis. For elemental analytics, such a traceability system is at present being set up. Laboratories at the working level are provided with the calibration means necessary for traceability via an intermediate level (e.g.: chemical calibration laboratories accredited within the Deutscher Kalibrierdienst (DKD, German Calibration Service)) or directly from national reference institutes (e.g. in the form of certified reference materials).

In chemistry the existing structures up to now can cover the becessary traceability chains only in part, so the traceability system is being further extended. The network is used to bundle the scattered technical competence available in the area of chemical analysis. The PTB as the institute entrusted by law with the realization, maintenance and dissemination of the units has a managing function here. Within the network, the tasks are distributed among the partners according to their competence and capacities. All partners participate on their own behalf in international key comparisons organized under an agreement between the national metrology institutes. Apart from the gain in efficiency, this structure allows a fast and practice-based estimate of the metrological needs which are continuously discussed with the users. A national network for metrology in chemistry is a new approach to coping with the numerous tasks in chemistry. The strategic approach in Germany has, therefore, raised worldwide interest.

Contact at PTB:

Phone: +49-531-592-0