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1.
Jean S. Kane 《Geostandards and Geoanalytical Research》2010,34(3):215-230
Reference materials (RMs) to support geoanalysis have a long history, dating back to the issuance of G-1 and W-1 in 1951. This paper addresses only one aspect of the most recent part of that history, the experience of the International Association of Geoanalysts (IAG) as a certifying body. In 2002, the Certification Committee of the IAG met in Potsdam to discuss becoming a certifying body able to produce RMs for the geoanalytical community. Following that meeting, the IAG developed and published a protocol to assure that IAG RMs would meet International Organization for Standardization (ISO) guidelines to the fullest extent possible. Many practical problems arise in the application of the recommendations of the ISO Guides to any one specific certification project. The recommendations describe the ideal; achievable reality is always somewhat less than that ideal, presenting a significant challenge to the IAG as a certifying body. This paper will summarise experience to date, while focusing on the most challenging issues, deriving uncertainties compliant with the Guide to Uncertainty in Measurement (GUM) and establishing traceability of certified values (CVs). 相似文献
2.
Jean S. Kane Bombor Batjargal Dorj Erdenetsetseg 《Geostandards and Geoanalytical Research》2009,33(3):295-308
A report is presented on the recertification of two certified reference materials (CRMs) initially prepared and certified by the Central Geological Laboratory of Mongolia (CGL), namely serpentinite GAS and alkaline granite OShBO. Subsequent work done in collaboration with the International Association of Geoanalysts (IAG) followed the International Organisation for Standardisation (ISO) guidelines for certification (ISO Guide 35, 2006) more closely than had been possible originally. The certification protocol followed was that of the International Association of Geoanalysts (IAG). The recertification added to the number of elements that were certified for OShBO (from 21 to 30), but not for GAS (decreased from 15 to 12) because of the greater analytical difficulties posed by that sample matrix in meeting the more stringent metrological requirements for recertification. Further, the uncertainties for these values were established in accordance with the Guide to Measurement Uncertainty ; individual contributions of heterogeneity and bias are reported as appropriate for each of the certified constituents. Traceability of the certified values was demonstrated to the greatest possible extent, based on concurrent analyses of the matrix-matched existing CRMs, SW and GM, by all participating laboratories. The materials are now available from the CGL for use by laboratories in controlling data quality when analysing materials of similar matrices. 相似文献
3.
Reference materials (RM) are essential to achieve traceability of measurements. Specific uses of RM in analytical laboratories are the validation of methods, the calibration of instruments, the quality control and the demonstration of proficiency. This paper describes the certification of a new geochemical reference material, named BRP-1 (Basalt Ribeirão Preto), and acts as the certificate of analysis for this RM. The rock sample was crushed and pulverised at the USGS (Denver, USA), homogenised and split into 1920 bottles, with 55 g each. BRP-1 was transported back to Brazil and the homogeneity between and within bottles was assessed to demonstrate sufficient homogeneity for certification. The chemical characterisation was performed by twenty-five laboratories. Each laboratory received two bottles of BRP-1 and one of BCR-2 (Basalt Columbia River) used for quality control (QC). Reference values and uncertainties were calculated for forty-four constituents of BRP-1, following ISO Guide 35 recommendations and the IAG Protocol. The calculation of each reference value included data of proven traceability from at least ten laboratories using two or more analytical techniques and the uncertainties combines the characterisation and between bottle homogeneity contributions. 相似文献
4.
Developments at ISO/REMCO and its Impact on the Production and Use of Geological Reference Materials
Angelique Botha 《Geostandards and Geoanalytical Research》2010,34(3):237-244
During the past decade the work of ISO/REMCO, the International Organization for Standardization’s Technical Committee on Reference Materials, was dedicated to achieving global harmonisation, and true involvement of the member countries. The first major accomplishment was the clarification of the terminology in the definitions for reference material and certified reference material, which were published as an amendment to ISO Guide 30 in 2008. The next milestone was the recognition that ISO Guide 34 (‘General requirements for the competence of reference material producers’) be used in conjunction with ISO/IEC 17025 for the accreditation of reference material producers. The third edition of ISO Guide 34 published in November 2009, clarifies the acceptable procedures for the certification of reference materials. This paper will discuss the role of ISO/REMCO in formalising the procedures for the accreditation of reference material producers and the evolution of the terms reference material and certified reference material. The paper will conclude with a case study, where a primary method in a single laboratory – one of the recognised acceptable metrologically valid procedures according to ISO Guide 34 – was used for the certification of reference materials. The reference materials are South African Reference Material SARM 2 (Syenite), SARM 3 (Lujavrite) and SARM 4 (Norite) from the suite of six NIMROCs that were originally certified by the Council for Mineral Technology (MINTEK) in South Africa in the 1970s. 相似文献
5.
Klaus Peter Jochum Jacinta Enzweiler Regina Mertz-Kraus Xiaohong Wang 《Geostandards and Geoanalytical Research》2010,34(4):353-385
This review gives an overview of the literature on reference materials of geochemical and environmental interest for the two-year period 2008–2009. Reference materials play an increasingly important role in all fields of geoanalytical research. This is demonstrated by the large number of publications containing data on reference materials. Although many reference materials exist, there is still a great need for certified samples, so-called delta zero materials for stable isotopic work and homogeneous microanalytical reference materials. This review focuses on six topics: developments of certification processes of reference materials mainly postulated in ISO guidelines and the IAG protocol, new developments of the GeoReM database, investigations of powdered rock reference materials, Chinese reference materials published in Chinese journals, microanalytical reference materials and isotopic reference materials. 相似文献
6.
Jean S. Kane 《Geostandards and Geoanalytical Research》2004,28(1):53-80
The International Association of Geoanalysts (IAG) has certified a slate sample, OU-6, for twelve major and minor constituents, as well as thirty-five trace elements through an interlaboratory programme conducted in close compliance with the International Organization for Standardization (ISO) Guide 35 (1989). Laboratories were qualified for participation in the certification programme, based on their performance in the prior analysis of OU-6 as a proficiency test material. Thirty laboratories provided data for the certification, though not for each constituent that was certified. Certification criteria included a means of establishing traceability for the certification data, generally through concurrent analysis of the existing Geological Survey of Japan reference material JSl-1, agreement of results between laboratories and methods, and a minimum of data rejection (4% rejection rate for OU-6 data and 6% for JSl-1 data), preferably for well-understood technical reasons only. Information values are provided for an additional eight constituents where certification criteria were not met. Uncertainties developed in accordance with the "Guide on Uncertainty in Measurement" (Eurachem 2000) and representing the 95% confidence interval of the certified and information values are reported for all fifty five constituents. The material is currently available in 40 g units for distribution by the IAG. Supply is anticipated to last about ten years. 相似文献
7.
黑色页岩样品中痕量级铂族元素地球化学成分标准物质研制 总被引：2，自引：2，他引：0
介绍了黑色页岩样品中6个铂族元素铂、钯、钌、锇、铑、铱的标准物质研制过程。黑色页岩样品采自贵州黄家湾,为一次采集、一次混样的原始样品,随机抽取包装好后的样品进行检验与定值。均匀性、稳定性符合要求后,按照国际标准化组织(ISO)34、35指南的基本要求和我国一级标准物质的技术规范,采用多个实验室协同测试的定值方式,利用不同原理的分析方法对此样品的6个铂族元素进行定值。以各实验室组数据作为最小统计单元,用Grubbs准则、Dixon法检验剔除离群数据,Shapiro-Wilk法检验各元素数据分布的正态性。检验结果100%的元素呈正态或近似正态分布。定值的6个元素均符合标准值水平。 相似文献
8.
Philip J. Potts Peter C. Webb Michael Thompson 《Geostandards and Geoanalytical Research》2019,43(3):409-418
ISO Guide 35:2017 provides, for the first time, an alternative way of characterising certified reference materials using proficiency testing. In this paper, the properties of assigned values derived from the well‐established GeoPT proficiency testing scheme are examined. This scheme, designed for laboratories that undertake the routine analysis of silicate rocks and related materials, routinely has over 100 participants contributing results. Following a detailed assessment of the metrological properties of GeoPT assigned values in relation to Guide 35 recommendations, it is demonstrated that these values may be regarded as certified values, provided a number of criteria are met. These criteria include the following: a demonstration of sufficient homogeneity of the candidate CRM; circulation, when judged to be appropriate, of an established matrix‐matched CRM for co‐analysis in that round; the robust statistical analysis of data sets using GeoPT established criteria; a decision whether assigning a value is justified (including a requirement of a minimum of fifteen valid results); and an expert group to manage the certification and the maintenance of appropriate records. In summary, the GeoPT proficiency testing scheme, subject to the arrangements summarised above, is considered to be competent for the certification of geological reference materials. 相似文献
9.
Tongxiang Ren Jun Wang Hai Lu Tao Zhou Yuanjing Zhou 《Geostandards and Geoanalytical Research》2016,40(2):227-238
Due to intensive research into selenium isotopes in recent years, the increasing requirement for reliable and comparable measurement results has created a strong demand for selenium isotopic certified reference materials (iCRM) that were previously not available. To address this, eleven selenium iCRMs were developed, including ten synthetic iCRMs (GBW 04447–GBW 04456) and one natural iCRM (GBW 04457). The synthetic iCRMs were prepared with 76Se, 78Se, 80Se and 82Se solutions and a natural selenium solution; the natural iCRM was prepared with highly pure selenium material. The property values of isotope ratios in these iCRMs were certified by calibrated mass spectrometry with a collision cell multi‐collector ICP‐MS. The mass discrimination effect of the instrument was corrected with corresponding 78Se/76Se isotope mixtures and 82Se/76Se isotope mixtures, which were gravimetrically prepared with purified, isotopically enriched selenium materials. Homogeneity and stability tests were performed, and no significant influences were found. The uncertainty of the property values of the iCRMs was evaluated according to the Guide to the Expression of Uncertainty in Measurement (GUM) of ISO/BIPM and ISO Guide 35. The δ82/76Se value of GBW 04457 relative to NIST SRM 3149 was also calculated. These iCRMs are intended for use in calibration of instruments and evaluation of methods for the determination of selenium isotope ratios. 相似文献
10.
The Use of Reference Materials: A Tutorial 总被引：2，自引：1，他引：2
Jean S. Kane 《Geostandards and Geoanalytical Research》2001,25(1):7-22
Any review of the analytical literature shows that, while reference materials are routinely used in laboratories world-wide, not all uses follow ISO Guide 33 (1989), which outlines best practices. Analytical data quality can suffer as a result. This paper reviews the various uses that the geoanalytical community has made of reference materials from a historical perspective, and suggests improvements in practice that would more closely follow ISO Guide 33 recommendations. 相似文献
11.
12.
Zhizhong Cheng Mei Liu Hongku Huang Tiexin Gu Weidong Yan Hongli Wen 《Geostandards and Geoanalytical Research》2015,39(2):221-232
The preparation and characterisation of three nickel ores and two nickel concentrate certified reference materials are described in this paper. The samples of nickel ore and nickel concentrate were collected from the Hongqiling nickel deposit in Jilin province. The raw materials were crushed and passed through a 2.0‐mm sieve. The rough samples were then ground for 48 hr in a high‐alumina ball mill to a final size of < 0.074 mm. Homogeneity of the samples was tested by X‐ray fluorescence spectrometry (WD‐XRF) and inductively coupled plasma‐atomic emission spectrometry (ICP‐AES). The relative standard deviations (RSD) of results on mass fraction measurements by WD‐XRF were < 1.0% m/m for eighteen components. F‐tests showed that all five samples were homogeneous. Nineteen laboratories contributed with measurement results (2127 in total) for the certification of mass fractions for twenty‐three elements and compounds. Twenty‐three components in the nickel ores and twenty components in the nickel concentrates were characterised as certified values, while the Ni mass fractions ranges from 0.1 to 9.02% m/m in these certified reference materials. These five samples were approved as national certified reference materials by the National Organisation of Reference Materials of China in 2012. 相似文献
13.
An Interpretation of ISO Guidelines for the Certification of Geological Reference Materials 总被引：3，自引：0，他引：3
Recommendations for the certification of reference materials, as published by the International Organisation for Standardisation (ISO), are reviewed and proposals made as to how they can be adapted for the certification of new geological reference materials. Whilst acknowledging the important contribution made by the large number of existing matrix-matched geological reference materials, it is recommended that future characterisation programmes should follow the ISO guidelines for certification, not the least so that laboratories can readily use the resultant samples to establish the traceability of geoanalytical results. 相似文献
14.
Jean S. Kane Philip J. Potts Thomas Meisel Michael Wiedenbeck 《Geostandards and Geoanalytical Research》2007,31(3):285-288
The International Association of Geoanalysts (IAG) published a protocol for the certification of reference materials in close accord with the International Organisation for Standardisation (ISO) guidelines (Kane et al. 2003). This article supplements that protocol, providing additional discussion of best approaches for pre-selecting laboratories for participation in certification projects. This discussion also makes a distinction between inter-laboratory certifications, where n = 15 is the general standard, and expert laboratory certifications, where a much smaller number of laboratories will be deemed qualified to provide data of the quality needed for certification. 相似文献
15.
Henry F. STEGER 《Geostandards and Geoanalytical Research》1981,5(2):189-193
The Canadian Certified Reference Materials Project has amended its procedure in interla-boratory certification programs. The reasons for reducing to one from two the number of bottles of a candidate reference materials submitted to each participating laboratory are discussed. The effect of the smaller number of results of the one-bottle approach to be expected on the certified value and 95% confidence interval is shown to be minor. 相似文献
16.
Dongyang Sun Jin Liu Chenzi Fan Linghao Zhao Xiuchun Zhan Mingyue Hu 《Geostandards and Geoanalytical Research》2023,47(1):7-22
Four CGSP (Chinese Geological Standard Powders) carbonate matrix element reference materials were prepared by a coprecipitation method. The major and trace elements were dissolved from natural rare earth carbonate raw materials in strong acid and precipitated with ammonium bicarbonate or ammonia to form carbonate matrix phases. The carbonate reference materials were ground and pressed into tablets for microanalysis. The element homogeneity and stability in CGSP reference materials were tested by LA-ICP-MS using a calibration strategy without an internal standard element and evaluated mainly following ISO Guide 35: 2017 and JJF 1343-2012. Although the homogeneity of most of elements in the CGSP series were comparable to the repeatability obtained from homogeneous glasses, some elements (e.g., Mo, Se, Ga, Ge, Cd, Ni, Co, U) were found to have some degree of heterogeneity. All of elements passed the t-test evaluation in a 32-month stability examination except for Mo in CGSP-A, Na, Ge, Mo in CGSP-B, Ni, Cd, Sn in CGSP-C, and Al, P, Tb, Ho in CGSP-D. The certified element mass fraction values and uncertainties were determined with the characterisation of a non-operationally defined measurand using various bulk analysis methods in eight laboratories. GGSPs will provide a new carbonate calibration reference option for microanalysis. 相似文献
17.
A Review of the IAG GeoPT™ and Certification Programmes,their Protocols,and the Differences between the Original and Potential Modifications to the Certification Protocol 
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下载免费PDF全文 Jean S. Kane 《Geostandards and Geoanalytical Research》2015,39(4):419-432
The IAG conducts two programmes, the GeoPT ? proficiency test and a certification programme that are closely interconnected. Both support the quality control/quality assurance activities of geochemical laboratories. Each derives an estimate of ‘true value’ for a number of samples, but arrives at that estimate, and its uncertainty, differently. This review discusses the history of the two programmes and compares the ‘true values’ and their uncertainties obtained through each. It then considers ‘fitness‐for‐purpose’ issues related to both GeoPT ? and certification uncertainties. Issues related to potential modification of the IAG protocol for certification are also considered. 相似文献
18.
The International Organisation for Standardisation (ISO) is a federation of national standards bodies that has developed a number of international agreements concerning the standardisation of various commercial and scientific activities which have been published as technical standards and guides. Several of the documents describe the way in which measurements should be made to ensure that all laboratories measuring the same quantity in the same material will produce results that are in harmony with one another. Others describe universally accepted practices for the production and use of reference materials. A summary of the ISO guides most relevant to the production of geochemical reference materials is presented; producers of these materials are encouraged to accept these guides in the interest of increasing the credibility and status of reference materials available to the geoanalytical community. 相似文献
19.
Molan Tang Bolun Fan Lingyang Yao Zhengyu Bao Huan Tian Zhenzhen Ma Ziyi An Ming Ma Hongyu Zhang Zhongbiao Fu 《Geostandards and Geoanalytical Research》2020,44(2):375-384
The preparation and characterisation of certified reference materials of four selenium‐rich rocks (GBW07397 to GBW07400) are described in this paper. The raw materials were derived from selenium‐rich rocks in two famous seleniferous regions, Enshi Prefecture, Hubei Province and Ziyang County, Shaanxi Province, China. Sample homogeneity and stability were tested by inductively coupled plasma‐mass spectrometry and atomic fluorescence spectrometry. The determined element mass fractions included selenium, arsenic, copper, zinc, molybdenum, cadmium, lead, vanadium and silver. Except for silver, the results of analysis of variance (ANOVA) and the relative standard deviations of the element mass fractions showed that the four materials exhibited good homogeneity and stability. Ten laboratories were involved in an interlaboratory comparison scheme for certification. Eight element mass fractions in the selenium‐rich rocks were assigned as certified values, while only indicative values were obtained for Ag mass fractions. The certified values and expanded uncertainties for the selenium mass fractions in GBW07397–GBW07400 are 0.96 ± 0.05, 1.03 ± 0.05, 49 ± 4 and 38.5 ± 1.9 μg g?1, respectively. 相似文献
20.
W.S. BOWMAN 《Geostandards and Geoanalytical Research》1995,19(2):101-124
This report describes the location, collection, preparation, mineralogy, homogeneity testing, and interlaboratory certification program of a diorite gneiss reference material, SY-4. This work was an undertaking of the Canadian Certified Reference Materials Project (CCRMP). SY-4 has been certified for 49 whole-rock, minor, and trace elements. Eight additional constituents have been provisionally certified and information ranges are reported for another 14 elements. 相似文献