Determination of a standard efficiency using the ISOCS uncertainty estimator for calculating the activity concentration of 226Ra, 232Th, and 40K in concrete

The Activity Concentration Index (ACI) requires knowledge of the activity concentrations of Ra, Th (Pb), and K, typically determined through gamma spectrometry. The inherent heterogeneity of concrete makes the determination of gamma counting efficiency a complex problem. For this reason, this study...

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Detalles Bibliográficos
Autores: Caño, Andrés, Suárez-Navarro, José Antonio, García Calvo, José Luis, Marzal García, Queralt, Alonso López, M. del Mar
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/391936
Acceso en línea:http://hdl.handle.net/10261/391936
Access Level:acceso abierto
Palabra clave:Activity concentration index
ISOCS
Uncertainty estimator
NORM materials
Gamma spectrometry
Concrete
Descripción
Sumario:The Activity Concentration Index (ACI) requires knowledge of the activity concentrations of Ra, Th (Pb), and K, typically determined through gamma spectrometry. The inherent heterogeneity of concrete makes the determination of gamma counting efficiency a complex problem. For this reason, this study employed the ISOCS Uncertainty Estimator (IUE), which allows for probabilistic calculations based on variations in parameters affecting counting efficiency, such as dimensions, density, and composition. The IUE enabled the estimation of a representative efficiency for a standard concrete configuration applicable to concrete specimens and samples from existing structures. The results obtained with the proposed efficiency for natural radionuclides of the uranium and thorium series, along with K, compared to the classical material grinding method, showed no significant differences in the mean and variance. The maximum differences observed when applying regression analysis were less than 16 %, thus validating the representative efficiency obtained with the IUE.