Community Research and Development Information Service - CORDIS


The Nuclear Signatures Inter-laboratory Measurement Evaluation Programme (NUSIMEP) has been established to support the growing need to measure the isotopic abundances of elements characteristic of the nuclear fuel cycle present in trace amounts in the environment. Such measurements are required for safeguards applications as well as for the implementation of the Non-Proliferation Treaty (NPT). Through this and similar programmes, the degree of equivalence of measurements from individual laboratories on the international scene can be ascertained. It complements the two other, long running programmes at the Institute for Reference Materials and Measurements (IRMM), the Regular European Inter-laboratory Evaluation Programme (REIMEP) in the nuclear field and the International Measurement Evaluation Programme (IMEP) in the field of non-nuclear chemical amount measurements.

The present campaign, NUSIMEP-3, follows NUSIMEP-2 in requiring measurements of uranium isotopic ratios but this time in saline matrices. This is a step towards having samples similar to environmental samples that commonly have to be analysed by field laboratories. The samples were prepared and certified at IRMM: uranium isotopic ratios by mixing certified isotopic material as UF6 and measuring minor isotopes by TIMS. The saline matrix solutions were prepared by dissolving salts to reach prescribed concentrations matching expected saline waters and the uranium concentration in these salt mixtures was measured by IDMS using the highly enriched 233U spike IRMM-073 and applying a quadrupole ICP-MS (ELAN 6000). The measured isotopic ratios are shown in a series of graphs for comparison.

Additional information

Authors: HELD A ET AL, European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Geel (BE)
Bibliographic Reference: EUR 20377 EN (2002), 41pp. Free of charge
Availability: Available from European Commission, JRC Knowledge Management Unit, Ispra (IT) Tel: +39 033278 9843 or +39 033278 9864 Fax: +39 033278 9623 E-mail:
Record Number: 200315871 / Last updated on: 2003-02-13
Original language: en
Available languages: en