Attributes Measurements by Calorimetry in 15 to 30 Minutes

An analysis of the early portion of the power-history data collected with both of the IAEA's aii—cooled bulk calorimeters has demonstrated that such calorimeters can measure the power from preheated containers of plutonium oxide with an accuracy of 2-51/. in 15 to 30 minutes. Material accountancy at plutonium facilities has a need for such a capability for measurement of Pu scrap. Also, the IAEA could use just two calorimeters and a gamma-ray assay system for reliable variables and attributes measurements of plutonium mass during a two-day physical-inventory verification (PW) at a mixed-oxide(MQX) fuel-fabrication facility. The assay results would be free of the concerns about sample moisture, impurities, and geometry that previously have limited the accuracy of assays based on neutron measurements.