Published Jul 12, 2021


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Gouda M. Mohamed

Riham S. Hegazy



This research article refers to the application of the evaluated measurement uncertainty for deciding the statement of conformity. It is a proposal to rethink about the classification of measuring devices, taking into account the calculations of uncertainty as a decision rule. It is also a base for complete compatibility and harmonization between ISO 17025:2017 and the other standards. To verify this proposal a case study on compression testing machine classification is used. This proposal aims to review classification criteria for these machines. Since the uncertainty value is equivalent to all parameters that may affect the performance of these machines, it is logical and accurate to use it as the basis for the classification. This approach may be employed for the upcoming version of ISO 7500 standard to use the uncertainty value as a base for machine classification.


Conformity statement, confidence level, decision rule, uncertainty estimation

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How to Cite
Mohamed, G. M., & Hegazy, R. S. . (2021). An investigation on using measurement uncertainty as decision rule for statement of conformity. Universitas Scientiarum, 26(2), 179–191.
Scientific and Industrial Metrology