Standard Test Method for Nondestructive Assay of Nuclear Material in Scrap and Waste by Passive-Active Neutron Counting Using a 252Cf Shuffler
|Publication Date:||10 June 2001|
|ICS Code (Special wastes):||13.030.30|
|ICS Code (Radiation measurements):||17.240|
1.1 This test method covers the nondestructive assay of scrap and waste for uranium and plutonium content using a 252Cf shuffler. Shuffler measurements provide rapid results and can be applied to a variety of matrix materials in containers as large as 208-litre drums. Corrections are made for the effects of matrix material. This test method has been used to assay items containing uranium, plutonium, or both. Applications of this test method include measurements for safeguards, accountability, TRU, and U waste segregation, disposal, and process control purposes (1,2,3).
1.1.1 This test method uses passive neutron coincidence counting to measure 238Pu, 240Pu, and 242Pu. It has been used to assay items with plutonium contents between 0.03 g and 1000 g. It could be used to measure other spontaneously fissioning isotopes. It specifically describes the approach used with shift register electronics; however, it can be adapted to other electronics.
1.1.2 This test method uses neutron irradiation with a moveable californium source and counting of the delayed neutrons from the induced fissions to measure 235U. It has been used to assay items with 235U contents between 0.1 g and 1000 g. It could be used to assay other fissionable isotopes.
1.2 This test method requires knowledge of the relative isotopic composition to determine the mass of the different elements.
1.3 This test method may give biased results for measurements of containers that include large quantities of hydrogen.
1.4 The techniques described in this test method have been applied to materials other than scrap and waste. These other applications are not addressed in this test method.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.