SNM measurement methods: the state of the practice

In order to determine the specific applications and performance of special nuclear materials (SNM) measurement methods being used routinely in nuclear fuel production facilities, a survey of users was conducted at 22 commercial and DOE plants. The methods used and their performance when applied to the wide range of uranium and plutonium materials encountered during processing were evaluated. The most frequently used methods for safeguards material control and accounting involve a combination of bulk measurement (weight or volume), sampling, and chemical assay/isotopic analysis, particularly for feed, intermediate products, and final products. Non-destructive assay methods are used on materials that are difficult to sample or dissolve (when chemical assay methods are ineffective), wuch as inhomogeneous, impure scrap and waste