INRiM contributions in the characterization and certification of reference materials

Abstract: The National Institute of Metrological Research (I.N.Ri.M.), in Italy, has among its duties the development, the maintenance and the dissemination of primary standards for establishing a correct traceability chain at national level. For this reason, I.N.Ri.M. has been developing research activities on reference materials, mainly in the chemical field, dealing both with the characterization and the certification of reference materials. The present paper focuses on the certified reference solutions for electrolytic conductivity, on the primary reference gas mixtures, and on I.N.Ri.M. contribution in the certification of various reference materials by determining trace element mass fraction by means of instrumental neutron activation analysis. The description of the main features of the produced reference materials, of the used procedures, and of the uncertainty evaluation are given.