Expanding needs for metrological traceability and measurement uncertainty

In our daily life, numerical evaluation of a quantity is normally required not only for scientific decision but also for judgment of products. Under the Metre Convention, ideal system of the International System of units (SI) is globally recognized and utilized in many fields of science and technology 1]. Some documented standards such as International Vocabulary of Metrology (VIM) 2], and Guide to the expression of Uncertainty in Measurement (GUM) 3] are edited and published by the Joint Committee for Guides in Metrology (JCGM) and commonly introduced in the fields of metrology, science and conformity assessment in connection with ISO/IEC 17025. This paper describes the recent situation in measurement science, and how to obtain a reliable measurement result using the expression of metrological traceability together with measurement uncertainty. In the paper, a response to Prof. Ludwik Finkelstein’s message for ‘challenges and problems to future advancement in measurement science’ is also reported.