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As part of Task C.35 (Calculation of Parameters for Inspection Planning and Evaluation) of the U.S. Program of Technical Assistance to IAEA Safeguards, Pacific Northwest Laboratory has performed some quantitative analyses of IAEA inspection activities at low-enriched uranium (LEU) conversion and fuel fabrication facilities. This report presents the results and conclusions of those analyses.Implementation of IAEA safeguards at LEU conversion and fuel fabrication facilities must take into account a variety of practical problems and constraints. One of the key concerns is the problem of flow verification, especially product verification. There are basically two kinds of difficulties:• The amount of inspection effort required for full flow verification can be quite large.• Given current measurement technology, no fully satisfactory measurement strategy for product verification is available.The objective of this report is to help put the problem of flow verification in perspective by presenting the results of some specific calculations of inspection effort and probability of detection for various product measurement strategies.Three basic product verification strategies can be defined:• verification of finished fuel assemblies • verification of fuel rods, supplemented by other inspection activities to cover fuel assemblies • verification of pellet stacks prior to their insertion into fuel rods, supplemented by other inspection activities to cover fuel rods and fuel assemblies.A fourth possibility is an appropriate combination of the three basic strategies; this combined approach has some advantages from the practical point of view.In order to provide quantitative information about the advantages and disadvantages of the various strategies, eight ~.pecific cases were examined.For each case, the technical approach was to define model facilities, outline the inspection strategy, and calculate the probability of detection and required inspection effort. When all cases were completed, the results were analyzed. On the basis of the conclusions, a number of supplemental inspection activities were identified and quantitative assessments were made of their impact on the overall inspection approach.For each of the eight case studies, plant throughputs of 200, 400 and 600 tons of uranium per year and plant inventories equal to 34% and 81% of annual throughput were considered. Operator measurement errors consistent with international standards of measurement accuracy were assumed. The following IAEA detection goals were postulated:• significant quantity = 75 kg 235 u contained in low-enriched uranium • detection probability = 95% • false alarm probability = 5% • detection time on the order of one yearThe key conclusion of the study concerns the effectiveness of the verification strategy that includes a) a limited variables sampling plan for verification measurements at the pellet loading station, b) a sampling plan for quantitative NDA verification measurements of fuel rods, and c) an attributes sampling plan for fuel assembly ve...