This is a joint WG with CITAC.

Terms of Reference

1. The EURACHEM/CITAC Measurement Uncertainty and Traceability Working Group has been established and will operate in accordance with the Constitution agreed in the EURACHEM Memorandum of Understanding.
2. The EURACHEM/CITAC Measurement Uncertainty and Traceability Working Group will prepare guidance for the evaluation of uncertainties and establishment of traceability in chemical analysis. This guidance will be applicable to all chemical analytical laboratories and will provide guidance on the assessment of uncertainties and establishment of traceability required for accreditation.
3. These guides will be developed in collaboration with EA and will be updated as experience is gained in their use.

Work Programme

Guides

• The Working Group produced the Eurachem Guide Quantifying Uncertainty in Analytical Measurement, first published in 1995 and now in its third edition, which was published in 2012. Several translations are available.
• The Eurachem guide Use of uncertainty information in compliance assessment, published in 2007, provides guidance on how uncertainty may be taken into account in deciding compliance with a limit.
• The Eurachem guide Setting and Using Target Uncertainty in Chemical Measurement, published in 2015, gives guidance on the important task of deciding target uncertainty; this helps to make sure that a procedure is fit for its intended purpose.
• In 2003 the Working Group published the first Eurachem guide on Traceability in Chemical Measurement, which was updated in 2019. This Guide gives principles and guidance for the establishment of measurement traceability in quantitative chemical analysis.

Information leaflets

The working group has so far published five information leaflets:

• Traceability for analytical measurement summarise the principles of metrological traceability in routine testing.
• Use of uncertainty information in compliance assessment summarises the principles of interpreting results against regulatory or other specification limits.
• Using repeated measurements to improve the standard uncertainty addresses a common problem: when it is appropriate to divide a standard deviation by the square root of the number of observations when evaluating uncertainty for random variation.
• Treatment of an observed bias discusses whether or not an observed significant bias should be corrected and the impact this may have on the measurement uncertainty (MU).
• The leaflet Setting Target Measurement Uncertainty gives a brief introduction to the topic and introduces the Guide on the topic.

In addition, the WG maintains the leaflet Measurement Uncertainty for Laboratory Customers, originally published by SP (now RISE) and elaborated with Eurolab and others to help customers understand why laboratories report measurement uncertainty.

Workshops

The Measurement Uncertainty and traceability working group has coordinated several International workshops on measurement uncertainty, including

• Evaluation of measurement uncertainty (Graz, 1994; Berlin, 1997, Lisbon, 2011)
• Measurement Uncertainty in Sampling and Compliance (Berlin, 2008)
• Eurachem Workshop: Quality in Analytical Measurements (Lisbon, 2014)
• Eurachem workshop on Uncertainty from sampling and analysis for accredited laboratories (Berlin, 2019)

Members*

*Last updated 2022-05-06

Contact

The working group may be contacted via the working group Secretary using the Website contact form.

• Measurement uncertainty
• Traceability
• Working groups

• Prev
• Next