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13. Measurement Uncertainty

Philip M. Fleischmann


„Sicher is’, dass nix sicher is, drum bin ich vorsichtshalber misstrauisch.“ (Karl Valentin)

One thing’s certain and that is that nothing is certain, so I’d rather be suspicious.

It is a horrible idea for users that measurements should be uncertain. Not to mention the measurements made by calibration laboratories! However, even the most accurate methods unfortunately have the unpleasant characteristic that their measurement uncertainty cannot be zero.


And this is exactly what the Technical Committee Measurement Uncertainty deals with.

Since the Technical Committee consists of participants from all Technical Committees, it is sometimes difficult to find a common set of general procedures providing the best solution to a problem. But maybe it is also the nature of the matter to be able to give only "approximately exact " information?


The Technical Committee is currently preparing a guideline on the application of decision rules and risk assessment. It is intended to provide the users in calibration laboratories with a practicable tool to be able to practically fulfil the essential points of the sections and of DIN EN ISO/IEC 17025:2018.


In addition, a guideline for the rounding of results and measurement uncertainties in calibration certificates as well as a guideline for the determination of calibration intervals with regard to the calculation of the measurement uncertainty are currently being prepared.


The Technical Committee has published the following guidelines:


·         DKD-L 5: Guide for the practice-oriented determination of measurement uncertainty – Basics

·         DKD-L 13-2: Validation of measurement uncertainty budgets