I  U  P  A  C

News & Notices

Organizations & People

Standing Committees







Links of Interest

Search the Site

Home Page












Provisional Recommendations

Analytical Chemistry Division

Interdivisional Working Party on Harmonization of Quality Assurance

Metrological Traceability of Measurement Results in Chemistry

In commerce, society, and science, metrological comparability* of measured quantity values and various published values is essential to determine their spatio-temporal differences, ratios, and drifts. Achieving metrological comparability of measurement results requires definition of calibration hierarchies providing metrological traceability chains which enable the establishment of metrological traceability of measured quantity values to a common metrological reference.
Experience has shown that the understanding of the concepts involved, their relation, role, definition, and use is insufficient and varied. Consequently, an attempt is made in this study to arrive at a set of consistent concept systems with associated terminology for measurement in chemistry. The systems build on definitions of concepts and associated terms from the new 3rd edition (2007) of the International Vocabulary of Metrology -Basic and General Concepts and Associated Terms - VIM, such as quantity, measurand, calibration, measurement procedure, measurement uncertainty, measurement standard, calibrator, reference material. Additional concepts such as metrological equivalence of measurement results are also given.
Flow charts of generic calibration hierarchies are presented as well as a variety of examples.
The establishment, assessment, and reporting of metrological traceability are discussed, including the needed metrological institutional hierarchy and the role of interlaboratory comparisons.

Recommendations are made about the essential steps in planning and performing a measurement, and reporting a measurement result.

* Bold face indicates a concept defined in this report, or in the VIM3.

> Download full text of the Provisional Recommendations (pdf file - 1.28MB)

Comments by 29 February 2008
Prof. Paul De Bièvre
TEL: +[32] 14 851 338
FAX: +[32] 14 853 908
E-MAIL: [email protected]

> see Project Description for access to later version (available online on 13 July 2009)

Page last modified 13 July 2009.
Copyright ©2007-2009 International Union of Pure and Applied Chemistry.
Questions or comments about IUPAC, please contact, the Secretariat.
Questions regarding the website, please contact Web Help.