IN-PLANT EVALUATION OF THE NDA OF HTGR FUEL

Two state-of-the-art nondestructive assay instruments, the LASL Random Driver and the LASL Segmented Gamma- Ray Scanner, are undergoing in-plant evaluation for the assay of HTGR fuel materials as part of a joint General Atomic Company/LASL effort for the improvement of HTGR fuel accountability. Test results include measurements of the instrument operating parameters such as stability, reliability, sensitivity to operating and environmental conditions, and ease of operation. Instrument performance results are also presented and error statements are given in terms of the calibration error, the reproducbility of measurement, the error caused by variable material from, and the bias relative to results obtained using sampling and chemical analysis.