A Nondestructive Assay Standards Program at the Savannah River Plant

To minimize accountability inventory differences, high accuracy standards are needed to complement recently developed high precision NBA instruments. A program to acquire specific material standards having the highest achievable accuracy was developed and successfully completed. The goal for this program was to define performance of NDA systems to at least 0.1% + 10 accuracy. Among sixteen standards that were evaluated, relative standard deviations from traceable values were better than 0.0^2%. This was a significant achievement by the four participating analytical laboratories, particularly considering dissolution difficulties of some of the materials. Value of this level of accuracy is significant since some NDA equipment installed in the process has achieved precision better than +0.1% +a of full range. These instruments with forecast good long-term stability and the high accuracy standards should significantly reduce ID's that would have resulted if current measurement techniques had been used.