THE IMPACT OF MEASUREMENT UNCERTAINTY ON CONFORMITY ASSESSMENT AGAINST TECHNICAL REQUIREMENTS
Keywords:
measurement result, measurement uncertainty, conformity assessment, technical requirements, decision rule, guard band, conformity limit, metrological reliabilityAbstract
This article investigates the impact of measurement uncertainty on the assessment of measurement results for conformity with specified technical requirements. Comparing a measurement result solely with the specified value and established tolerance limits may, in certain cases, lead to incorrect decisions regarding conformity or non-conformity. Therefore, it is essential to account for measurement uncertainty, particularly expanded uncertainty, and the limit values of technical requirements when assessing conformity. The article analyses the interrelationship between measurement results, measurement uncertainty, technical specification limits, and decision rules. The metrological aspects of using guard bands and decision rules in conformity assessment are also examined. The findings demonstrate that taking measurement uncertainty into account enables reliable, impartial, and metrologically justified decisions regarding conformity with technical requirements. The proposed approach can be applied in testing and calibration laboratories, as well as in assessing the conformity of products and processes with specified technical requirements.
References
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Phillips, S. and Krystek, M. Assessment of Conformity, Decision Rules and Risk Analysis (2014)
Joint Committee for Guides in Metrology (JCGM). Evaluation of measurement data — Guide to the expression of uncertainty in measurement. JCGM 100:2008 (GUM). BIPM, 2008.
