JRC releases IRMM-3000a, the diluted version of the IRMM-3000 highly enriched uranium (HEU) reference material series

Why is important

The reduced uncertainties of the ²³⁵U enrichment for the IRMM-3000 and IRMM-3000a series reference materials allow a significant improvement of precision and accuracy for the analysis of highly enriched nuclear material. This type of reference material is needed by nuclear safeguards authorities to monitor the use and prevent the proliferation of highly enriched uranium material, commonly used in enrichment facilities, nuclear weapons facilities and for the production of medical isotopes, for example 99Mo for 99mTc generators. In addition, the diluted IRMM‑3000a series includes enough uranium for high sensitivity mass spectrometers calibration, such as multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) and is therefore also suitable for use in scientific areas such as geochemistry and cosmochemistry.

JRC Contribution

By offering the diluted IRMM-3000a series, JRC makes this valuable series of reference materials available to an extended user community.

Unique preparation

Like the IRMM-3000 series, the IRMM-3000a series of uranium nitrate solution reference materials includes five materials with different isotopic compositions, covering a range from 20 % to 90 % for the enrichment of ²³⁵U. The relative uncertainties of the isotope ratios ²³⁵U/²³⁸U and the ²³⁵U enrichment have an unprecedented level of 0.02 % (95 % confidence level), due to the gravimetrical preparation.

More information

The preparation and certification of the IRMM-3000a and IRMM-3000 series of reference materials are described in the JRC certification report: Preparation and Certification of Highly Enriched Uranium Nitrate Solutions, IRMM-3000 Series

The IRMM-3000a series can be ordered from the certified reference materials online catalogue of the European Commission's Joint Research Centre (JRC).