The total U-235 load in the defined irradiation specimens can be determined by the gamma scanning technique with a precision of at least ±2％at the 95^ confidence limits. The homogeneity of these specimens, total uranium-235 per l/8" increment of specimen length, can be determined with a precision of about ±3.5％ for 8 wt ％uranium (93-2％ U-235) fuel and about ±5% for 4 wt ％uranium fuel. These precision values are for a counting time of 1 min/increment. The total fuel load may be biased by 0.6％ in the unlikely event that a specimen is fabricated with a constant thickness at the extreme of the thickness tolerance. A single determination of homogeneity and fuel load for these specimens re¬quires about one hour. This analytical time can be reduced by scanning larger increments of specimen length or by decreasing the length of time for which each Increment is counted. Precision is inversely proportional to the square root of total counting time.
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