44644 2018 eng lecture 0 -- -- -- Measurement results and scientific models leading to important decisions in forensics, food fraud or climatology are based on isotope ratio data. Molar masses of multi-isotopic elements are as well based on isotope ratio data. Thus, in the case of Si, isotope ratios directly impact the redefinition of the SI base units kilogram and mole. Therefore, new strategies are required leading to new primary isotope reference materials, whose isotope ratios are traceable to the SI. This in turn will ensure the comparability of isotope ratio data and will render the traceability exception requested by the CCQM superfluous. Such new procedures will be developed for the key elements S, Si, Ca, Sr and Nd at relative uncertainty levels of ≤ 0.01 %. EURAMET TC-MC Meeting Vienna, Austria 05.02.2018 06.02.2018 0 Jochen Vogl eng uncontrolled Metrology in chemistry eng uncontrolled Isotope amount ratio eng uncontrolled SI traceability eng uncontrolled Atomic weight eng uncontrolled Molar mass eng uncontrolled Synthetic isotope mixtures Analytische Chemie Datei im Netzwerk der BAM verfügbar ("Closed Access") Präsentation