Ion implantation of 226Ra for a primary 222Rn emanation standard

Laser resonance ionization at the RISIKO 30 kV mass separator has been used to produce isotopically and isobarically pure and well quantified 222Rn emanation standards. Based upon laser-spectroscopic preparation studies, ion implantation into aluminum and tungsten targets has been carried out, providing overall implantation efficiencies of 40% up to 60%. The absolute implanted activity of 226Ra was determined by the technique of defined solid-angle α-particle spectrometry, where excellent energy resolution was observed. The 222Rn emanation coefficient of the produced targets was studied using α-particle and γ-ray spectrometry, and yielded results between 0.23 and 0.34, with relative uncertainty on the order of 1%. No dependence exceeding a 1% change of the emanation on humidity could be identified in the range of 15 %rH to 75 %rH, whereas there were hints of a slight correlation between the emanation and temperature. Additionally, and as expected, the emanation coefficient was found to be dependent on the target material as well as the implanted dose. © 202

Standoff UV-C imaging of alpha particle emitters

Alpha particles are proven to be very useful in many areas of medicine, technology and science. Yet, they represent the biggest risk to soft biological tissues compared to all nuclear decay products when ingested or inhaled, implying thus stringent radiation protection measures in the management and monitoring of samples that emit them. In this paper we present a standoff optical imaging approach that enables sensing of a radiological threat items at facilities where alpha-emitting material is manufactured, handled, used and stored, at safe distances without putting personnel at risk or contaminating equipment. The optical imaging of alpha-emitting samples is based on the radiation induced air luminescence (radioluminescence) in the UV-C (solar-blind) spectral region which enables detection of alpha particles even under bright light conditions. We show that by adding trace amounts of nitric oxide into the nitrogen atmosphere surrounding the sample, alpha sources with specific activities as low as 1.5 Bq/cm(2) can be remotely imaged. This work provides a proof-of-concept implementation of a novel imaging approach that not only enhances capabilities of a state to take actions which effectively mitigate consequences of an radiological emergency for the society, health, environment and economy, but also benefits nuclear industry in decommissioning efforts.Peer reviewe

New metrology for radon at the environmental level

International audienc

Testing of the measuring instruments in non-governmental networks for the purpose of environmental monitoring of ionising radiation

Non-governmental networks for environmental monitoring employ a wide range of radiation protection instruments from different manufacturers, which provide the public with often unreliable dosimetric data. These Measuring Instruments in Non-governmental Networks (MINN) are mostly based on Geiger-Muller tube gas detectors, which represent low-cost easily operated instruments. An extensive testing of these devices was performed in order to validate the data acquired with MINN within the 16ENV04 Preparedness EMPIR project. In total, 16 different dosemter types were selected, with a sample size of four dosemeters per dosemeter type. Performance testing included the energy dependence and the linearity tests of the dosemeter response. Additionally, during the Researcher Mobility Grant associated with the 16ENV04 project, two Geiger-Muller based dosemeter types, with a sample size of two dosemeters per type were included in the testing. These instruments were subjected to the angular dependence testing in both horizontal and vertical planes, besides the energy dependence and linearity tests in the reference Cs-137 field at Physikalisch-Technische Bundesanstalt (PTB). For all the dosemeter types, inherent background, response to secondary cosmic radiation and the response to small changes of dose rate were determined at the metrological facilities of PTB. The sensitivity of the measuring instruments used in non-governmental networks to small variations of the ambient dose equivalent rate was examined by exposing the dosemeters to low dose rate Cs-137, Co-60 and Ra-226 radiation sources, in order to estimate the effect of environmental radioactive contamination with artificially produced radionuclides. For the comparison purposes, besides the measuring instruments used in non-governmental networks, a previously characterized CdZnTe-based spectrodosemeter was irradiated with the aforementioned radiation fields. The measured values were compared with a reference Reuter-Stokes ionisation chamber used for low-dose rate level measurements.RAP 2020 : International conference on radiation applications; Book of abstracts; Virtual conference, 202

Investigation into the performance of dose rate measurement instruments used in non-governmental networks

In the aftermath of a nuclear or radiological accident, an extended mapping of reliable dose rate values is of key importance for any governmental decision and countermeasures. Presently, numerous dosimetry network stations, operated by the national governments of the member states in Europe, provide such dose rate data on an hourly basis. Nevertheless, there are large areas in Europe that are not covered at all by these early warning networks and other areas that show only a low density of governmental network stations. Hence, there may be a significant lack of information in case of a nuclear or radiological emergency. As a consequence of the Fukushima Daiichi nuclear power plant accidents in 2011, a number of non-governmental radiation monitoring networks (NRMN) appeared on the internet, providing dose rate data based on stationary as well as on mobile measurements of ionizing radiation by laypersons. Especially the mobile detectors are able to cover large areas in short time. Therefore, it is of considerable importance to investigate the feasibility of using dose rate data from non-governmental networks as a complementary input to the European Radiological Data Exchange Platform (EURDEP). Within the European Metrology Program for Innovation and Research (EMPIR), the project 16ENV04 “Preparedness” has studied the metrological relevance of such non-governmental dose rate data (also called crowd-sourced radiological monitoring) in the most comprehensive way so far. Sixteen different dose rate detector systems (in general 4 of each type, plus 2 types with 2 detectors, i.e. 68 detectors in total) used in NRMN have been investigated for the reliability of their data and the corresponding networks, and their data provision to the public were analyzed. The most relevant performance parameters of dosimetry systems (detector's inherent background, energy dependence and linearity of the response as well as the response to secondary cosmic radiation, the sensitivity to small increases of the dose rate and finally the stability of the detector's indication at various climatic conditions - temperature and humidity) have been investigated for fourteen representative types of non-governmental dose rate measuring instruments. Results of this comprehensive performance study of the simple, light-weighted and cheap dose rate meters used in NRMN, and conclusions on the feasibility of using their data for governmental monitoring in case of a nuclear or radiological emergency are presented. © 2021 The Author

Development of 222Rn Emanation Sources with Integrated Quasi 2π Active Monitoring

In this work, a novel approach for the standardization of low-level 222Rn emanation is presented. The technique is based on the integration of a 222Rn source, directly, with an α-particle detector, which allows the residual 222Rn to be continuously monitored. Preparation of the device entails thermal physical vapor deposition of 226RaCl2 directly onto the surface of a commercially available ion implanted Si-diode detector, resulting in a thin-layer geometry. This enables continuous collection of well resolved α-particle spectra of the nuclei, decaying within the deposited layer, with a detection efficiency of approximately 0.5 in a quasi 2π geometry. The continuously sampled α-particle spectra are used to derive the emanation by statistical inversion. It is possible to achieve this with high temporal resolution due to the small background and the high counting efficiency of the presented technique. The emanation derived in this way exhibits a dependence on the relative humidity of up to 15% in the range from 20% rH to 90% rH. Traceability to the SI is provided by employing defined solid-angle α-particle spectrometry to characterize the counting efficiency of the modified detectors. The presented technique is demonstrated to apply to a range covering the release of at least 1 to 210 222Rn atoms per second, and it results in SI-traceable emanation values with a combined standard uncertainty not exceeding 2%. This provides a pathway for the realization of reference atmospheres covering typical environmental 222Rn levels and thus drastically improves the realization and the dissemination of the derived unit of the activity concentration concerning 222Rn in air

Menschenwürde als Leitkategorie für professionelles Entscheiden und Handeln im Pflege- und Gesundheitswesen

Röttger N, Stoecker R. Menschenwürde als Leitkategorie für professionelles Entscheiden und Handeln im Pflege- und Gesundheitswesen. In: Riedel A, Lehmeyer S, eds. Ethik im Gesundheitswesen. Springer Reference Pflege – Therapie – Gesundheit. 1st ed. Berlin und Heidelberg: Springer; 2022: 1-21.Die menschliche Würde spielt in der Ethik der Pflege eine zentrale Rolle. Das zeigt sich aus der Perspektive der Pflegenden, wenn es z. B. in der Präambel des ICN Code of Ethics for Nurses heißt: „Inherent in nursing is a respect for human rights, including cultural rights, the right to life and choice, to dignity and to be treated with respect“. Es kennzeichnet aber auch die Perspektive der Gepflegten, etwa im ersten Satz der Präambel der Charta der Rechte hilfe- und pflegebedürftiger Menschen: „Jeder Mensch hat uneingeschränkten Anspruch darauf, dass seine Würde und Einzigartigkeit respektiert werden“. Dabei ist es gerade in der Pflegeethik auffallend, dass die Würde sowohl einen fundierenden Charakter hat als Grundlage aller moralischer Beziehungen, als auch konkret einen Maßstab für bestimmte Verpflichtungen bietet (Menschen nicht zu „entwürdigen“)

Attempt to estimate the background pulse height spectrum of the CeBr3 scintillation spectrometer due to terrestrial gamma ray components: Application in environmental radiation monitoring

This article describes an attempt to estimate the background (BG) pulse height spectrum (PHS) of the CeBr3 scintillation spectrometer due to terrestrial gamma ray components. In radiological emergencies, there are some cases which the prior measurement of the background components can\u27t be made. By subtracting the BG components from the measured gross PHS, timely and accurate information about the artificial radionuclides involved in the emergencies would be effectively drawn to protect the member of the public and first responders. A Monte Carlo calculation was conducted to simulate the PHS by gamma rays from natural radionuclides uniformly distributed in the ground. The calculated PHS were verified to be consistent with measured PHS. Derived dose equivalent rate from the calculated PHS were compared with reference value and found to be in good agreement with each other. The study revealed that applying the calculated PHS to the in-situ gamma ray spectrometry components hardly affected the determination of surface deposition density on soil for radioactive cesium