Ionising radiation metrology for the metallurgical industry

Every year millions tons of steel are produced worldwide from recycled scrap loads. Although the detection systems in the steelworks prevent most orphan radioactive sources from entering the furnace, there is still the possibility of accidentally melting a radioactive source. The MetroMetal project, carried out in the frame of the European Metrology Research Programme (EMRP), addresses this problem by studying the existing measurement systems, developing sets of reference sources in various matrices (cast steel, slag, fume dust) and proposing new detection instruments. This paper presents the key lines of the project and describes the preparation of radioactive sources as well as the intercomparison exercises used to test the calibration and correction methods proposed within the project.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Assessment of the uncertainty budget associated with 4pi-gamma counting

The 4pig-counting technique is recognized as a powerful primary method for the standardization of radionuclides decaying with abundant gamma emissions. Based on the use of a gamma detector in quasi 4pi-geometry, a detection efficiency close to 100% and a low uncertainty can be achieved thanks to the summing effect of subsequent gamma transitions. Uncertainties have to be assigned to the realistic modelling of the source-detector geometry with respect to dimensions, density and material composition, the calculation of the total counting efficiency of the detector for the various emitted radiation and the effect of possible flaws in the decay scheme of a radionuclide on the calculated total efficiency. Other uncertainty factors pertain to typical metrological sources of uncertainty, such as weighing, nuclear counting with pulse pile-up and system dead-time effects, impurity corrections, decay corrections, timing and frequency, etc. In order to ensure good metrological practices at NMIs, the uncertainties particular to the method are discussed.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Review and assessment of pool scrubbing models

Centro de Informacion y Documentacion Cientifica (CINDOC). C/Joaquin Costa, 22. 28002 Madrid. SPAIN / CINDOC - Centro de Informaciòn y Documentaciòn CientìficaSIGLEESSpai

Editorial: Documentaliste et chercheur, un couple qui s’ignore ?

Document en libre accèsEditorialManque de communication, disparition des bibliothécaires, nouvelles attentes de la recherche, mutation des métiers, ignorance des nouveaux outils documentaires par les directions...Tels sont les points saillants qui ressortent de l'atelier Dialogu'IST organisé récemment par le réseau national des professionnels l'information scientifique (Renatis), visant à recenser les enjeux de l'information scientifique et technique (IST). Selon Magali Damoiseaux et Danielle Cristofol,les trois quarts des documentalistes ont dû se reconvertir vers de nouveaux métiers liés à la bibliométrie, la communication,la formation, l'informatique, le web, ou l'édition avec en général peu de moyens. Avec la disponibilité des publications sur internet, de nombreux laboratoires n'ont plus recruté de personnels de l'IST, perdant ainsi le contact local. Certaines disciplines s'en sortent mieux que d'autres, c'est le cas des sciences humaines et sociales où les postes restent abondants en raison d'une politique prioritaire en édition scientifique interne, alors que les sciences physiques et biologiques ont confié la diffusion de leurs travaux aux éditeurs privés. Plus surprenant, le papier n'a pas disparu dans certains domaines, c'est le cas des mathématiques où les chercheurs apprécient toujours les vieux grimoires ! Difficultés à avoir des articles récents ou anciens, il est plus facile de travailler sur une longue durée avec du papier. li y a donc une hétérogénéité des métiers qui dépend des disciplines et des politiques institutionnelles

Radioactive waste management: Review on clearance levels and acceptance criteria legislation, requirements and standards

In 2011 the joint research project Metrology for Radioactive Waste Management (MetroRWM) of the European Metrology Research and Development Program (EMRP) started with a total duration of three years. Within this project, new metrological resources for the assessment of radioactive waste, including their calibration with new reference materials traceable to national standards will be developed. This paper gives a review on national, European and international strategies as basis for science-based metrological requirements in clearance and acceptance of radioactive waste.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Characterisation of a radionuclide specific laboratory detector system for the metallurgical industry by Monte Carlo simulations

One of the outputs of the European Metrology Research Programme project “Ionising radiation metrology for the metallurgical industry” (MetroMetal) was a recommendation on a novel radionuclide specific detector system optimized for the measurement of radioactivity in metallurgical samples. The detection efficiency of the recommended system for the standards of cast steel, slag and fume dust developed within the project was characterized by Monte Carlo (MC) simulations performed using different MC codes. Capabilities of MC codes were also tested for simulation of true coincidence summing (TCS) effects for several radionuclides of interest in the metallurgical industry. The TCS correction factors reached up to 32 % showing that the TCS effects are of high importance in close measurement geometries met in routine analyses of metallurgical samples.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Interlaboratory comparison on 137Cs activity concentration in fume dust

A comparison was conducted, between 11 European National Metrology Institutes and EC-JRC, on measurement of 137Cs activity concentration in fume dust. As comparison material an activity standard produced from real contaminated fume dust was used. The standard material consisted of 13 samples of compressed fume dust, each of 50 g mass and of well-defined cylindrical geometry (diameter 69.5 mm and height 18.7 mm). The material contained 137Cs and 60Co of reference activity concentrations of (9.72 ± 0.10) Bq/g and (0.450 ± 0.018) Bq/g, respectively, determined using the comparison results. The organisation and results of the intercomparison, as well as the process of obtaining reliable reference values are presented.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Characterisation of a radionuclide specific laboratory detector system for the metallurgical industry by Monte Carlo simulations

Kierrätysmetallia hyödyntävissä metallisulattamoissa saattaa lopputuotteena saatavaan teräkseen tai muuhun materiaaliin joutua radioaktiivisia aineita. Tuotteen radiologinen puhtaus todetaan yleensä laboratoriomittauksin. Artikkelissa kuvataan eurooppalaisessa metrologian tutkimusohjelmassa kehitetty optimaalinen mittausjärjestely, jolla epäpuhtaudet havaitaan mahdollisimman tehokkaasti. Mittausjärjestelmän ominaisuuksia on testattu laskennallisia menetelmiä käyttäen