• 품질경영학회지
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• 제45권3호
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• pp.447-462
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• 2017

Purpose: This study aims to develop distributable samples that can be used for proficiency testing to verify the ability of the testing laboratory to perform high temperature and low temperature tests. Method: In this study, the temperature-resistance characteristics of the NTC thermistor were used to develop samples. The homogeneity and stability of samples were examined according to the proficiency testing requirements. Results: Thirty samples with homogeneity and stability were developed and used for the proficiency testing. Thus, it was possible to distinguish between the test laboratories that showed satisfactory results and those that did not. Conclusion: It was the first time to develop samples that can be used for proficiency testing in high temperature and low temperature tests. and it was proved that the proficiency test program can be operated using the characteristics of NTC thermistor.

• 한국물환경학회지
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• 제31권1호
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• pp.49-54
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• 2015

Acute toxicity test with Daphnia magna has a variety of factors such as incubation condition of test species, food quality and proficiency of laboratory workers. Therefore, proper proficiency testing samples were required for evaluating the competence of laboratory workers. This study aims to propose some appropriate proficiency testing samples for laboratory workers of acute toxicity test with Daphnia magna. Proposed four kinds of standard samples (Sample A, B, C, and D) for proficiency testing were selected from reference materials which were recommended from Canada and USA WET(Whole Effluent Toxicity) authorities. Proposed standard samples were tested by trial application of proficiency testing, homogeneity and stability checks using repeatability test. Sample A, C and D were estimated ad the suitable candidates for proficiency test standard samples except for Sample B. In addition, Sample A was proved to be the most suitable sample.

• 한국물환경학회지
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• 제29권4호
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• pp.568-573
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• 2013

In this study, we conducted whole effluent toxicity (WET) proficiency testing based on the results which $EC_{50}$ value of 3 types (A, B, C) unknown samples calculated from 32 water quality measurement agencies in Korea. WET proficiency testing was expected to their improve of analysis skill and ensure reliability of analysis results. Ultimately, it is intended to promote the reliable enforcement of WET. WET proficiency testing was evaluated using the z-score, robust z-score and the results showed that 30 participating agencies were "compliance". In addition, $EC_{50}$ values of "unknown sample A" were the normal distribution. Therefore, "unknown sample A" was considered as the most suitable standard toxicity substance.

• 한국산업보건학회지
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• 제30권1호
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• pp.58-66
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• 2020

Objectives: The objective of this study was to develop formaldehyde samples for quality control (QC) and to test the applicability of proficiency analytical testing in Korea. Methods: We made formaldehyde samples with certified standard solutions (formaldehyde in water or acetonitrile) and 2,4-dinitrophenylhydrazine (2,4-DNPH)-coated silicagel tubes. Four levels of formaldehyde concentration were tested for storage stability at room temperature and at 4℃ over three months. Analytical proficiency testing was performed with four or 36 institutes. Results: Formaldehyde sample tubes were easily made through the injection of standard solutions and the average efficiencies of recovery were 95-101%. The coefficients of variation (CV) of the formaldehyde samples were 1.39-2.55%. The recovery efficiencies fell between 90% and 110% at the concentration range of 1-10 ㎍/sample over three months storage at refrigerated and room temperature. The CVs were less than 5% in the proficiency analytical testing. By adjusted proficient ranges, 64% of the results of the second proficiency analytical testing were acceptable. Conclusions: The formaldehyde samples made by injection on 2,4-DNPH-coated silicagel tubes were stable and applicable for quality control.

• 한국물환경학회지
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• 제30권6호
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• pp.632-637
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• 2014

Proficiency testing by interlaboratory comparisons is used to determine the performance of individual laboratories. In order to verify the quality of acute toxicity testing with Daphnia magna, National Institute of Environmental Research in South Korea is regularly organizing interlaboratory comparisons to estimate the analytical accuracy of different laboratories. Total 58 laboratories located in South Korea took part in interlaboratory proficiency testing scheme with three proficiency testing samples. TU(Toxic Unit) values of each laboratory were determined and robust z-score was calculated in order to evaluate the proficiency levels. Based on the robust z-score classification, 74% of the participant laboratories showed a satisfactory performance (43 laboratories). The main reason of 'unsatisfactory' performance seemed to be considered that the unsuitable management of test organism incubation system and the lack of experience on the identification of the test organism condition by effect of toxicity.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.586-591
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• 2003

This paper describes the result of proficiency testing by inter-laboratory comparisons for braking lining. Proficiency testing provides an objective means of assessing and demonstrating the validity and reliability of test results produced by laboratories. To more accuracy comparison test for braking lining test, they will be made the same test procedure and environment conditions.

• 한국대기환경학회지
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• 제16권1호
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• pp.69-77
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• 2000

This paper summerizes the results of the first proficiency testing program for achieving the analytical quality assurance of anions and metal ions in air borne particles in Korea. This program covered the chemical testing of anions(Cl-, NO3-, SO42-) and metals(Fe, Pb, Zn) in qeueous solution. The exercies was conducted by the Measurement & Analysis Committee of Korean Society for Atmospheric Environment(KOSAE). Pilot lab. was Division of Chemical Metrology and Materais Evaluation in Korea Research Institute of Standards and Science(KRISS). A total of 11 laboratories participated in the program. Two samples of 100mL in low density polyehylene bottles were supplied to participating laboratories. The proficiency testing results were interpreted by two graphical methods, Youden polt and x-Charts(control chart).

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2005년도 추계학술대회
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• pp.389-400
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• 2005

This paper introduces measurement Quality Management System(QMS) (KSA ISO 10012:2004), and general requirements for the competence of testing, inspection and calibration laboratories(KSA 17025:2000 and KSA 17020:2000) and proficiency testing by interlaboratory comparisions(KS A ISO/IEC Guide 43-1, 2:2002).

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1149-1154
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• 2010

Liquid chromatography/mass spectrometry using isotope dilution method has been established as a primary method for the measurement of cortisol in human serum. Verification of this method was accomplished by the participation in Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM) pilot study. Two levels of cortisol certified reference materials were prepared and certified by the established method. They were used as sample materials for the proficiency testing. The expanded uncertainty in the measurement of cortisol in human serum was approximately 1.2% at 95% confidence level. The results of the proficiency testing showed a good precision among the participants, but some bias to the certified values. This means that commercial field laboratories should keep traceability chain to SI unit through available reference measurement procedures and/or available reference materials.

• 분석과학
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• 제23권3호
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• pp.284-294
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• 2010

하천수 시료를 이용한 중금속분석용 수질표준물질, NIER-I08RW 및 NIER-I09를 제조하여 납, 카드뮴, 크롬, 구리 등 중금속 4 종에 대한 인증분석 및 불확도 등을 평가하였다. 균질성 평가 결과, 병간균질도가 숙련도시험의 목표표준편차의 0.3 배 이하로서 숙련도시험용 시료로서 사용하기에 충분히 균질한 시료인 것으로 확인되었다. 제조된 표준물질을 이용하여 국내 환경측정분석기관을 대상으로 숙련도시험을 실시하고, 설정값의 설정방법에 따른 로버스트 Z 값의 변동을 비교하였다. 다른 항목에 비해 농도가 낮은 NIER-I08RW의 카드뮴 항목을 제외하고는, 특성값과 참가기관의 합의값의 차이인 상대편차, $B_{relative}$는 모두 ${\pm}$1 이하로서 크지 않았으며, 설정값을 달리 설정함으로 Z 값이 달라진 경우는 46 개로서 전체의 2.9%에 불과하였다.