1.1This test method covers the nondestructive assay of scrap and waste items for U, Pu, or both, using a ²⁵²Cf shuffler. Shuffler measurements have been applied to a variety of matrix materials in containers of up to several 100 L. Corrections are made for the effects of matrix material. Applications of this test method include measurements for safeguards, accountability, TRU, and U waste segregation, disposal, and process control purposes (1, 2, 3).2

1.1.1This test method uses passive neutron coincidence counting (4) to measure the ²⁴⁰Pu-effective mass. It has been used to assay items with total Pu contents between 0.03 g and 1000 g. It could be used to measure other spontaneously fissioning isotopes such as Cm and Cf. It specifically describes the approach used with shift register electronics; however, it can be adapted to other electronics.

1.1.2This test method uses neutron irradiation with a moveable Cf source and counting of the delayed neutrons from the induced fissions to measure the ²³⁵U equivalent fissile mass. It has been used to assay items with ²³⁵U contents between 0.1 g and 1000 g. It could be used to assay other fissile and fissionable isotopes.

1.2This test method requires knowledge of the relative isotopic composition (See Test Method C1030) of the special nuclear material to determine the mass of the different elements from the measurable quantities.

1.3The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4The 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.

1.5This 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.