Experience of the International Association of Geoanalysts as a Certifying Body

Abstract

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).

Geostandards and Geoanalytical Research Bibliographic Review 2011

“…This is shown by the production and certification procedures of new CRMs and their increasing use by geoanalysts. Although powdered rock RMs are the backbone of geoanalysis (Kane ), there is currently a great interest in microanalytical and environmental samples as well as isotopic RMs. This is indicated by some examples of the 2011 literature.…”

GGR Biennial Critical Review: Analytical Developments Since 2010

“…Historically, geochemical RMs were produced using the best practices available (Kane , Meisel and Kane ). The necessity to follow and apply metrological principles motivated the International Association of Geoanalysts (IAG) to elaborate a protocol for the certification of geochemical RMs, with procedures compliant to ISO/REMCO guidelines (Kane et al .…”

“…, ). The main goal of the IAG certification programme is to achieve target uncertainties that are both metrologically valid and are fit for purpose (Kane ). The characterisation of candidate RMs is mainly performed by experienced laboratories, selected on basis of their performance during the analysis of samples with similar matrix in the Geo PT ™ Proficiency Testing (PT) programme, which is regularly run by IAG.…”

“…The characterisation of candidate RMs is mainly performed by experienced laboratories, selected on basis of their performance during the analysis of samples with similar matrix in the Geo PT ™ Proficiency Testing (PT) programme, which is regularly run by IAG. Kane () exemplifies the calculation of combined uncertainties of certified values and also discusses the achievements and needs of the IAG certification programme. Recently, it has became apparent that the IAG protocol needs to undergo revision to comply with the new editions of ISO Guides 35 and 34 (Meisel and Kane ).…”

“…Powdered rock RMs are the backbone of geoanalysis (Kane ). Inspection of the literature shows that most geochemists use these samples to demonstrate their data quality.…”