Working Party on Harmonization of Quality Assurance
Metrological Traceability of Measurement Results
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
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
* 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: + 14 851 338
FAX: + 14 853 908
> see Project Description for access to later version (available online on 13 July 2009)