Non-destructive measurement methods for large scale gaseous diffusion process equipment

Two measurement methods have been developed to measure non-destructively uranium hold-up in gaseous diffusion plants. These methods include passive neutron and passive γ ray measurements. An additional method, high resolution γ ray spectroscopy, provides supplementary information about additional γ ray emitting isotopes, γ ray correction factors, 235U/234U ratios and 235U enrichment. Many of these methods can be used as a general purpose measurement technique for large containers of uranium. Measurement applications for these methods include uranium hold-up, waste measurements, criticality safety and nuclear accountability