Metrology for Chemical Engineers

The first full-semester course on Quality Assurance in Chemical Measurement was held at the Technical University of Denmark from September to December 1999. The course required sufficient knowledge of basic statistics to understand and apply the methods recommended in ISO 5725-1/6 Accuracy of Measurement Methods and Results.

The main purpose of the course was, however. to familiarize PhD students with the BIPM philosophy, using the International Organization for Standardization (ISO) Guide to Expression of Uncertainty in Measurement, which was accepted by IUPAC and other international scientific organizations in 1993. Chemists are notoriously reluctant to accept the BIPM philosophy, but the appearance of a new Draft Guide Quantifying Uncertainty in Analytical Measurement at the EURACHEM Workshop in Helsinki in June 1999 stimulated us to make an attempt to overcome such chemical prejudice.

After thorough reading of the examples presented in the Draft Guide. each of the participating students had to prepare an uncertainty budget for their own particular project and present it to the other participants for discussion. Eventually the students learned how to verify their uncertainty budgets by means of experimental results. this invariably entailed a reevaluation of the uncertainty components in the original budget.

The revised budget was again verified. and this iteration was continued until the budget correctly predicted the uncertainty of individual results covering the whole range of applicability of the analytical method. The paper presents the detailed structure of this first course. as well as improvements in the next course scheduled for the year 2000.