SNM Monitor Applications: Diversion Safeguards for Emergency Exits and Detection of Undeclared Feed in Enrichment Plants

摘要

A new monitor for special nuclear material (SNM) uses wide plastic scintillators and digital logic to achieve a higher sensitivity for detecting uranium than is found in conventional personnel SNM monitors. With its detectors spaced 2 m apart, the new monitor meets the DOE requirement to detect a 10-g metal exp 235 U sphere of 93% exp 235 U whose total mass is 10.8 g. This capability suits the monitor to scan people who may have to pass quickly through emergency exits. In yet another application, the monitor meets detection goals for detecting freshly separated, natural UF sub 6 that is brought into enrichment plants through personnel portals. To determine the performance of the new monitor for these applications, laboratory source scans and measurements of the growth of uranium daughter activity in freshly separated UF sub 6 were used.