Methodology and Analysis of the ILCs Provided by INRIM from 2016 to 2018

To assess the technical competence of calibration laboratories, national accreditation bodies (NABs) take into account the results of national and/or international proficiencies testing (PTs) including the inter-laboratory comparisons (ILCs). As the Italian NAB stopped acting as PT provider since 2015 due to the result of a peer assessment by the European co-operation for accreditation, the National Institute of Metrological Research (INRIM) reorganized itself and reoriented part of its activity to become a ILCs provider, thus supporting the calibration laboratories. This paper describes how INRIM has been organized as ILCs provider to guarantee the accreditation activity continuation and gives information about the main typologies of the provided ILCs and details on the analysis of the ILCs results in different metrological areas. From 2016 to 2018, INRIM provided 114 ILCs, in the areas of acoustics ultrasonic and vibration, electricity and magnetism, length (L), mass (M) and thermometry (T), involving 138 laboratories, for which 375 ILC reports were issued.