Perspectives on detection limits for nuclear measurements in selected national and international programs

Issues involving the definition and practical significance of detection limits are discussed in the light of US and international programs in which the concept plays a central role. The US program relates to the lower limit of detection (LLD) which forms a part of the technical specifications for nuclear power reactors, as required by the US Nuclear Regulatory Commission for measurements of effluent and environmental radioactivity. The programs of the International Atomic Energy Agency, which are oriented toward coordinated research and technical cooperation, similarly require common understanding and use of the limit of detection (LOD) as a practical and meaningful performance characteristic for measurements of trace elements in bioenvironmental matrices. Efforts to meet the needs of these two programs to formulate realistic and practicable detection limits will be reviewed, with special focus on problems-in-common such as the treatment of the blank, decision criteria, algorithm and assumption dependence, and the reporting of subliminal results