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Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement (v.7, #4)
Twenty-five years of international collaboration in reference materials via ISO/REMCO by Henry F. Steger (pp. 134-145).
This paper looks back on a quarter century of history of the Council Committee on Reference Materials of the International Organization for Standardization – REMCO. It begins however with the period before its formation in 1976 to describe how the Committee came into being as a response to a growing need by the analytical community for the number and variety of reference materials (RMs) as well as a need for the assurance of the quality of RMs and ends with a view of REMCO activities in the near future. This is not intended as a detailed history but instead to describe the evolution of REMCO by identifying major activities and accomplishments of REMCO.
Keywords: Keywords ISO/REMCO; Reference materials; ISO Guides
Improvements in performance in medical diagnostics tests documented by interlaboratory comparison programs by Daniel W. Tholen (pp. 146-152).
There is evidence to support the notion that interlaboratory comparisons (ILCs) are an effective tool for laboratory improvement. However, despite widespread experience and anecdotal evidence of improvements there are few published studies demonstrating any benefits from ILCs– in any field of testing. Published demonstrations of benefits can help justify the growing use of ILCs. ILCs and proficiency testing have been common for many years in medical laboratories; there has been open information on the results of ILCs, and there has been standardization of results from thousands of laboratories. These studies show general improvement over time in several areas of testing in different countries. Many articles cite specific reasons for the improvements, either proven or supposed. An early version of this paper was presented at the International Laboratory Accreditation Cooperation Conference ”ILAC 2000” in Washington D.C., on 31October, 2000.
Keywords: Keywords Proficiency testing; Interlaboratory comparisons; Medical laboratories; Review
Calibration uncertainty by K. Heydorn; Thomas Anglov (pp. 153-158).
Methods recommended by the International Standardization Organisation and Eurachem are not satisfactory for the correct estimation of calibration uncertainty. A novel approach is introduced and tested on actual calibration data for the determination of Pb by ICP-AES. The improved calibration uncertainty was verified from independent measurements of the same sample by demonstrating statistical control of analytical results and the absence of bias. The proposed method takes into account uncertainties of the measurement, as well as of the amount of calibrant. It is applicable to all types of calibration data, including cases where linearity can be assumed only over a limited range.
Keywords: Keywords Metrology in chemistry; Calibration; Uncertainty; Traceability; Verification
MiC in Chemistry Curriculum at the University of Tartu: the current status by I. Leito; E. Koort; Koit Herodes; Ivari Kaljurand (pp. 159-162).
The introduction of MiC (Metrology in Chemistry) into the Chemistry Curriculum at the University of Tartu using a two-stage approach is described. As the first stage the topics of MiC are first touched at the beginning of the first analytical chemistry lecture course in the 3rd semester. The emphasis there is on the measurement uncertainty (MU) and its practical estimation (based on the ISO GUM approach). The main purpose of this is to make it clear from the beginning that MU is an integral part of any measurement and to enable the students to estimate MU in the laboratory courses of analytical chemistry (3rd and 4th semesters). As the second stage, MiC is treated in more detail in a dedicated course where also topics, such as reference materials, interlaboratory comparisons, standardization, quality management, accreditation, etc are covered.
Keywords: Keywords Metrology in chemistry; Measurement uncertainty; Teaching; Undergraduate studies; Analytical chemistry.
Determination of the purity of potassium iodate by constant-current coulometry by L. Ma (pp. 163-167).
This paper describes a method of determining the purity of potassium iodate by constant-current coulometry. The determination can be divided into two steps. First, a Na2S2O3 solution is prepared and its reductive value is determined. Second, the purity value of an oxidimetric quantity of potassium iodate is determined. This paper discusses the conditions of the reaction process and evaluates type A and B standard uncertainty of this method. The expanded relative uncertainty of this method is 0.02% (k=2).
Keywords: Keywords Potassium iodate; Constant-current coulometry; Oxidimetric quantity
Announcing the collaboration between the European co-operation for Accreditation and the Institute for Reference Materials and Measurements: Improving the metrological basis of the European accreditation system for chemical measurements
by P. Taylor; K. Brinkmann; I. Papadakis; L. Cortez; M. Bednarova; Y. Aregbe (pp. 168-168).
The Operational System of National Accreditation of Laboratories in China by Qiao Dong (pp. 171-172).
This document gives a brief introduction to CNACL (China National Accreditation Committee for Laboratories). Laboratory accreditation in China is integrally administrated by the China State Bureau of Quality and Technical Supervision, a government administrative department of China State Council, which authorizes CNACL to implement Chinese laboratory accreditation activities. CNACL was established on September 20, 1994. It is a full member of both ILAC (International Laboratory Accreditation Cooperation), and APLAC (Asia Pacific laboratory Accreditation Cooperation), and signed the APLAC MRA (Mutual Recognition Arrangement) in New Delhi, India on December 3, 1999. CNACL carries out laboratory accreditation activities in full compliance with international general criteria. Its operation complies with ISO/IEC Guide 58 (1993), ISO/IEC 17025 (1999), ISO/IEC Guide 43 (1997) and other international standards.
Keywords: Keywords Laboratory accreditation; Testing; Calibration; Management system