FEDERAL STATE UNITARY ENTERPRISE “STATE SCIENTIFIC CENTER – RESEARCH INSTITUTE OF ATOMIC REACTORS’

The first plutonium and uranium NDA specimens were manufactured in 1980s, since the development and intensive investigations of mixed fuel for BOR-60 reactor were under way at RIAR, and the IAEA was interested in the issues of control and storage of this attractive nuclear material. The following working standards (WSt) were manufactured under the Agency’s Support Program and used for non-destructive assay (NDA) training during IAEA inspectors courses: - Several dismountable fuel assemblies (FDA) containing MOX fuel and uranium dioxide 90, 36, 21% enriched in uranium-235; - Nine WSt containing PuO2 and MOX fuel of up to 0.8 kg mass in cylindrical stainless capsules 44 mm in diameter, 145 mm high, and 2 mm thick; - Five sets of “quasi-infinitely” thick metal uranium enrichment standards each with 235U mass fractions range from 0.3 to 90%. Note. Two sets of such standard originally called UERM (Uranium Enrichment Reference Material) were delivered to IAEA in 1990. The remaining three sets were certified as State Uranium Isotopic and Mass Standards (SUIMS) in 2004. The SUIMS were enlisted into the State Register as SS 8433-2003. For the last decade all the work on the state standards at RIAR was performed under U.S./Russian Program on Nuclear Materials Protection, Control and Accounting (MPC&A). The work was financed by Oak Ridge National Laboratory to support MC&A measurements. New types of dioxide Uranium Enrichment Standards (UESt) for NDA and radiation sources to calibrate and test handheld and portal monitors for the MPC&A system were developed under this program.