Analysis and discussion on influence components of uncertainty in gas meter calibration devices

During the review process of metrological institution standardization assessments, it was observed that numerous municipal and county-level metrological institutions inadequately considered the influence components of uncertainty in the uncertainty evaluation of gas meter calibration devices. This reflects a lack of in-depth understanding among some laboratory personnel regarding the uncertainty influences of such devices. In particular, older devices, constrained by the technical and economic limitations of their time, are equipped with relatively simple supporting metrological equipment. This inevitably leads to more complex sources of uncertainty, which are often overlooked in practical evaluations. To address this issue, this paper systematically identifies and comprehensively considers various uncertainty influence components, using the uncertainty evaluation of gas meter calibration devices at the Hebei Institute of Metrological Supervision and Inspection as a case study. The aim is to provide a reference for relevant metrological institutions.