How Accreditation improve our quality of life? - Take Weight/Balance Calibration and Uncertainty Evaluation for example

Abstract

Weights and balances are instruments commonly used in laboratories, industries and on the markets. The accuracy and precision of weights and balances would directly affect the data results as well as fair trade. As we know, the different calibration methods chosen by calibration laboratories usually cause different results on both measurement data and uncertainty analysis. In order to enhance the equivalence and mutual recognition of calibration results obtained by laboratories performing calibration of weights and balances, here, TAF (Taiwan Accreditation Foundation) provide an document called "Technical Criteria for Weights/Balances Calibration in Calibration Field" for our accredited laboratories. It gives general idea for the establishing of calibration procedures. The information presented in this document is intended to use as technical requirements for accredited calibration laboratories for performing weights/balances calibration and evaluating measurement uncertainty. In addition, the assessors of TAF should use this document as the basis for on-site assessment and laboratory accreditation. The document contains basic requirements for the static calibration of weights and balances, such as calibration procedure including test of repeatability, error of indication, environmental condition, determination of the uncertainty of measurement, contents of calibration certificates, etc. For calibration laboratories, the uncertainty analysis is one of the important tasks for ISO/IEC 17025 laboratory accreditation. The evaluation results of uncertainty analysis, which perform in the calibration measurement capability (CMC) and scopes of accreditation, usually represent the capabilities and competence in measurement. Since all measurement have an associated uncertainty, it is crucial that the main parameters which can influence the quality of measurement result should be recognized. In order to reduce and identify possible errors, it is necessary to use correct calibration methods. Thus, some main parameters which should be recognized and included in the uncertainty budget also have been written in this document.