Extremity ring dosimetry intercomparison in reference and workplace fields

An intercomparison of ring dosemeters has been organised with the aim of assessing the technical capabilities of available extremity dosemeters and focusing on their performance at clinical workplaces with potentially high extremity doses. Twenty-four services from 16 countries participated in the intercomparison. The dosemeters were exposed to reference photon ((137)Cs) and beta ((147)Pm, (85)Kr and (90)Sr/(90)Y) fields together with fields representing realistic exposure situations in interventional radiology (direct and scattered radiation) and nuclear medicine ((99 m)Tc and (18)F). It has been found that most dosemeters provided satisfactory measurements of H(p)(0.07) for photon radiation, both in reference and realistic fields. However, only four dosemeters fulfilled the established requirements for all radiation qualities. The main difficulties were found for the measurement of low-energy beta radiation. Finally, the results also showed a general under-response of detectors to (18)F, which was attributed to the difficulties of the dosimetric systems to measure the positron contribution to the dose

Active personal dosemeters in interventional radiology: tests in laboratory conditions and in hospitals

The work package 3 of the ORAMED project, Collaborative Project (2008-11) supported by the European Commission within its seventh Framework Programme, is focused on the optimisation of the use of active personal dosemeters (APDs) in interventional radiology and cardiology (IR/IC). Indeed, a lack of appropriate APD devices is identified for these specific fields. Few devices can detect low-energy X rays (20-100 keV), and none of them are specifically designed for working in pulsed radiation fields. The work presented in this paper consists in studying the behaviour of some selected APDs deemed suitable for application in IR/IC. For this purpose, measurements under laboratory conditions, both with continuous and pulsed X-ray beams, and tests in real conditions on site in different European hospitals were performed. This study highlights the limitations of APDs for this application and the need of improving the APD technology so as to fulfil all needs in the IR/IC field

Etude d’un dosimètre individuel passif multi-élément pour la dosimétrie des neutrons

La dosimétrie individuelle des neutrons est actuellement effectuée à partir de méthodes peu satisfaisantes, soit par l’utilisation d’émulsions nucléaires qui sont “aveugles” pour les énergies inférieures à 1.5 MeV, soit par la mise en œuvre de détecteurs à albédo qui doivent être étalonnés aux divers postes de travail car leur réponse varie considérablement en fonction de l’énergie des neutrons. Les auteurs présentent l’état actuel des études du projet DINEM, Dosimètre Individuel “Neutrons” à Eléments Multiples. Il est constitué d’un dosimètre à albédo “PGP-DIN” qui détecte les neutrons d’énergie inférieure à 7 keV et d’un détecteur solide de traces qui détecte les énergies supérieures à 100 keV. Les derniers progrès enregistrés sur l’utilisation du CN 85 comme détecteur solide de traces laissent entrevoir une solution prochaine au problème difficile de la dosimétrie individuelle

Eurados trial performance test for neutron personal dosimetry

This paper reports on the results of a neutron trial performance test sponsored by the European Commission and organised by EURADOS. As anticipated, neutron dosimetry results were very dependent on the dosemeter type and the dose calculation algorithm. Fast neutron fields were generally well measured, but particular problems were noted in the determination of intermediate energy fields and large incident angles, demonstrating the difficulties of neutron personal dosimetry. Of particular concern from a radiological protection point of view was the large number of results underestimating personal dose equivalent. A considerable over-response was noted in a few cases

Report of IRPA task group on issues and actions taken in response to the change in eye lens dose limit

In 2018, the International Radiation Protection Association (IRPA) established its third task group (TG) on the implementation of the eye lens dose limit. To contribute to sharing experience and raising awareness within the radiation protection community about protection of workers in exposure of the lens of the eye, the TG conducted a questionnaire survey and analysed the responses. This paper provides an overview of the results of the questionnaire.Postprint (published version