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Main text CCQM-K143 is a key comparison that assesses participants' ability to prepare single element calibration solutions. Preparing calibration solutions properly is the cornerstone of establishing a traceability link to the International System of Units (SI), and therefore should be tested in order to confirm the validity of CCQM comparisons of more complex materials. CCQM-K143 consisted of participants each preparing a single copper calibration solution at 10 g/kg copper mass fraction and shipping 10 bottled aliquots of that solution to the coordinating laboratory, the National Institute of Standards and Technology (NIST). The masses and mass fraction for the prepared solutions were documented with the submitted samples. The solutions prepared by all participants were measured at NIST by high performance inductively coupled plasma optical emission spectroscopy (HP-ICP-OES). The intensity measurements for copper were not mapped onto values of mass fraction via calibration. Instead, ratios were computed between the measurements for copper and simultaneous measurements for manganese, the internal standard, and all subsequent data reductions, including the computation of the KCRV and the degrees of equivalence, were based on these ratios. Other than for two participants whose measurement results appeared to suffer from calculation or preparation errors, all unilateral degrees of equivalence showed that the measured values did not differ significantly from the KCRV. These results were confirmed by a second set of ICP-OES measurements performed by the Physikalisch-Technische Bundesanstalt (PTB). CCQM-K143 showed that participants are capable of preparing calibration solutions starting from high purity, assayed copper metal. Similar steps are involved when preparing solutions for other elements, so it seems safe to infer that similar capabilities should prevail when preparing many different, single-element solutions. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Electrolytic conductivity measurement is one of the important parameters to evaluate the concentration of dissolved substances in a solution and has been widely used in various fields of life, science, and technology. It was being used for process control and quality assurance. The traceability of the measuring results is a crucial requirement to guarantee reliability. The electrochemistry laboratory - chemical metrology Indonesia has started to develop a secondary method for electrolytic conductivity measurement. The objective of this work is to provide a traceability chain for electrolytic conductivity measurement in Indonesia through secondary reference material of Potassium Chloride (KCl) 1 M. The secondary reference material of KCl 1 M can be used as a standard for calibrating the conductivity meter, especially in seawater analysis. The secondary reference material that is developed has an electrolytic conductivity value of about 111 mS/cm and was measured using cell type D from ZMK, Germany. This cell is made from glass with two platinization electrodes inside. The distance of the electrodes is 60 mm, and the diameter of the electrode is 20 mm. The uncertainty measurement was estimated according to the ISO GUM recommendation by identifying all possible uncertainty sources in the electrolytic conductivity measurement process. The result showed that the expanded uncertainty of electrolytic conductivity measurement for KCl 1 M by a secondary method using cell type D was 0.33% at k=2 for 95% confidence level with a repeatability of the measurements and cell constant as the biggest sources of uncertainty which contributed as 80% and 17%, respectively.

Besi (Fe) dan Seng (Zn) merupakan unsur yang berguna bagi manusia. Keberadaan logam Fe dan Zn dalam produk perikanan yang cukup kecil (trace), mudah tekontaminasi oleh kondisi lingkungan, dan metoda preparasinya yang komplek menyebabkan penentuan logam Fe dan Zn ini cukup sulit, sehingga perlu dicari suatu metoda uji  yang valid dan akurat. Dalam penelitian ini dilakukan pengembangan metoda standar American of Analytical Chemistry (AOAC) tahun 2005 no. 999.10 dengan menggunakan bahan acuan bersertifikat DORM 3 (Fish Protein Certified Reference Material for Trace Metal) dari National Research Council of Canada (NRCC) untuk menguji keakuratan dan ketertelusuran hasil ke Standard Internasional (SI). Metoda ini sudah divalidasi berdasarkan parameter-parameter kimia analitik. Hasil penelitian menunjukkan rata-rata kadar Fe dan Zn dalam sampel perikanan sebesar 178 ±  14 mg.Kg-1  dan 59,8 ±  6,6 mg.Kg-1 (berat kering) dengan faktor cakupan 2 dan tingkat kepercayaan 95%, yang berada pada rentang yang ditentukan 183,5 ± 4,3 mg Kg-1 and 60 ± 1,1 mg Kg-1.Kata kunci : Fe, Zn, trace, CRM, perikanan Iron (Fe) and Zink (Zn) are  essential elements for human being. Determination of this elements in fish products is quite difficult because of Fe and Zn content  in trace level, easy to be contaminated by the environmental conditions, and, complex preparation methods so that it is needed to find a good and accurate method. In this paper, we have developed a standard method from American of Analytical Chemistry (AOAC), 2005, no. 999. using DORM 3 as Certified Reference Materials (CRMs) to check accuracy and traceability’s results to Standard International (SI). The method has been validated according to analytical parameters.  The results showed that means of Fe and Zn concentration in the investigated fish product were 178 ±  14 mg.Kg-1 and 59.8 ±  6,6 mg.Kg-1 respectively with coverage factor 2 and 95%  level of confident, and  in range of expected mass were 183,5 ± 4,3 mg.Kg-1 and 60 ± 1,1 mg.Kg-1in dry basis.Keywords : Fe, Zn, trace, CRM, fisher

As a consequence of the globalization of trade and industries, the presence of an accurate and traceable measurement has become very important for quality assurance of a product or service in the market, including pH measurement. pH measurement is a basic analysis used in a wide variety of applications, such as agriculture, wastewater treatment, industrial processes, research and development, and environmental monitoring. The reliable and comparable results of pH measurement are advantaged as one of the parameters for quality control that will affect the decision making. The Electrochemistry Laboratory under Deputy of National Measurement Standard – National Standardization Agency of Indonesia (SNSU–BSN) has a main duty to ensure the reliability, comparability, and traceability of pH measurements in Indonesia, as a commitment in building chemical metrology infrastructure. In this article, all the activities related to the establishment of traceability chain for pH measurement in Indonesia are comprehensively discussed. As of currently, the Electrochemistry Laboratory has successfully developed the secondary method for pH measurement using differential potentiometric cell, production of certified reference material (CRM) for buffer solution (oxalate, phthalate, phosphate, and borate buffer), dissemination by proficiency testing (PT) schemes for pH measurement, participation in the key comparison (KC) of APMP.QM-K91 for phthalate buffer, and claim submission for the Calibration Measurement Capabilities (CMCs) of phthalate buffer (pH 3.97-4.03) with expanded uncertainty 0.004.