Field Of Radiation Protection Research Articles

The reconstruction of 3D radiation field based on sparse measurement data

With the development of nuclear technology, an increasing number of occupational workers are exposed to radioactive environments. The three-dimensional(3D) dose rate field is of great significance in the radiation protection field. Many researchers focus on the reconstruction of 2D radiation fields but few of them paid attention to the reconstruction of the 3D dose rate field based on sparse measurement data. In this work, the net function interpolation method is introduced to reconstruct 3D radiation field using sparse sampling nodes. In contrast to traditional dose rate interpolation methods, we interpolated the value of the inverse of the dose rate. By using the inverse, the field to be interpolated follows a power function, which fits the net function much better than the direct interpolation. The proposed method includes interpolation on sampling grid lines, interpolation on sampling grid plane and interpolation in the three-dimensional space. Additionally, four simulation experiments are carried out to prove the effectiveness and accuracy of the proposed method. The first two cases are radiation fields formed by a single radioactive source without and with shielding. Radioactive environments caused by multiple radioactive sources without and with shielding are conducted in Case 3 and Case 4. The reconstruction radiation field is compared to the radiation field simulated by the Monte Carlo method. The average relative errors of the four cases are 0.82%, 2.13%, 1.71% and 4.27% respectively using approximately 1% measurement data. The experimental data provided by other researchers are also used to validate the effectiveness of the proposed method and the minimum relative error of Case 5 is 4.67%. Therefore, the net function is an interpolation method suitable for the radiation field and it can reconstruct the 3D radiation field accurately with sparse data.

Radiation attenuation properties of novel glass system using experimental and Geant4 simulation

The purpose of this study is to estimate the radiation shielding capacities of glass systems with the system of 45 SiO2 – 15 CaO – (40-x) BaO – (x) ZnO (where x = 0,10,20, 30, and 40 wt%). The mass attenuation coefficients, μ/ρ of these glasses have been calculated by using XCOM software and Geant4 simulation toolkit tool in the energy range of 0.0595 MeV–1.410 MeV. The experimental data have been carried out using a narrow beam using the NaI(Tl) scintillation detector at the energies of (59.52 KeV) 241Am, (661.66 keV) 137Cs, (1173.23, 1332.50 keV) 60Co, 152Eu(121.78, 244.69, 344.28, 964.13, 1408.1 KeV). The MAC calculated results were compared with the experimental values. There have been good agreements noticed. The other attenuation parameters were calculated such as the linear attenuation coefficient (μ), half value layer (HVL), mean free path (MFP) and the effective atomic number (Zeff). The attenuation results of this glass system were compared with some recently published commercial glasses, and the results showed that this glass system is important in the radiation protection field.

Radiation risk perception among parents and legal representatives of children undergoing radiological examinations

Risk communication is one of the stages of health risk analysis and is an interactive process of exchange of information and opinions about risks, including medical risks, between risk assessment specialists, decision makers, the media, stakeholder groups and the public. In organizing interaction with stakeholders in the risk communication process, sociological research helps to explore the attitudes of the actors. One of risk communication situations in the field of radiation protection is information provision to patients and their legal representatives about radiation health risks due to the medical radiology examinations. The aim of this study was to assess the radiation risk perception among parents and legal representatives of children undergoing radiological examinations. Parents and legal representatives of children undergoing hospital treatment from November 2021 to March 2022 were interviewed in a large pediatric infectious diseases hospital. A questionnaire designed at St. Petersburg Research Institute of Radiation Hygiene was used for the interviews. In total, 125 people were interviewed. The study showed that there were no significant differences in the perception of radiation risks among parents and legal representatives of children undergoing inpatient treatment with different socio-demographic characteristics. The level of knowledge was not identified as a factor shaping a tolerant attitude toward medical radiation risks. Parents and legal representatives of children undergoing hospital treatment show high rates of trust in the attending physicians and medicine in general. The study results show that those who have been informed about the risks generally have lower risk perception for radiological medical examinations than those who have not been informed about the risks.

Microwave assisted synthesis, photoluminescence and X-ray/gamma ray absoprtion properties of red CaZrO3:Eu3+ perovskite

Nanocrystalline orthorhombic CaZrO3:Eu3+ (1–4 ​mol%) perovskite was synthesized by microwave assisted combustion method. To know the phase purity, functional group, surface morphology, structural analysis and energy band gap, the synthesized sample was characterized by using various techniques. The powder X-ray diffraction analysis clearly confirms the formation of pure orthorhombic phase of CaZrO3:Eu3+ (1–4 ​mol%) nanoparticles. The surface morphology shows the formation of voids and pores which is the characteristic of combustion method. The d-spacings, selected area electron diffraction pattern and the crystallite size obtained from transmission electron microscopic analysis matches well with that of X-ray diffraction pattern.The optical energy band gap determined from Wood and Tauc's relation decreases with decrease in crystallite size and with increase in dopant concentration. The photoluminescence emission excited at 306 ​nm wavelength shows the characteristic peaks of Eu3+ ions. CIE and CCT coordinates clearly shows that CaZrO3:Eu3+ (1–4 ​mol%) nanophosphor is one of the promising candidate for display applications. Further, the interaction of X-ray/gamma radiation with CaZrO3:Eu3+ is also studied. We have reported the X-ray/gamma radiation interaction parameters such as mass attenuation coefficient and other parameters at different energies. The established data may be useful in the fields of radiation protection. Calcium and Zirconium being heavier elements, there is an expectation that, the CZ perovskite might be a good X-ray/gamma ray absorber and hence X-ray/gamma ray interaction parameters are discussed.

放射線防護分野を元気にするために

放射線防護分野を元気にするために

Effect of the new photoatomic data library EPDL2017 to mass attenuation coefficient calculation of materials used in the nuclear medicine facilities using EpiXS software

The accuracy of the photoatomic cross-section data is of great importance in the field of radiation protection, particularly in the characterization of radiation shielding materials. With the release of the latest and probably the most accurate photoatomic data library, EPDL2017, the need to re-evaluate all the existing and already established mass attenuation coefficients (MACs) of all radiation shielding materials arises. The MACs of several polymers, alloy-based, glasses, and building materials used in a nuclear medicine facility were investigated using the EPDL2017 library embedded in EpiXS software and were compared to MACs available in the literature. The relative differences between MACEpiXS and MACXCOM were negligible, ranging from 0.02% to 0.36% for most materials. However, for material like a glass comprising of elements Te and La evaluated near their corresponding K-edge energies, the relative differences in MACs increased up to 1.46%. On the other hand, a comparison with MACs calculated based on EPDL97 (a predecessor of EPDL2017) revealed as much as a 6.61% difference. Also, it would seem that the changes in MACs were more evident in the materials composed of high atomic number elements evaluated at x-ray energies compared to materials composed of low atomic number elements evaluated at gamma-ray energies.

DESIGN AND FABRICATION OF A PEDIATRIC THYROID PHANTOM FOR USE IN RADIO-IODINE UPTAKE MEASUREMENT, IMAGE QUALITY CONTROL AND DOSIMETRY.

Estimating internal contamination from 131I for children in nuclear accidents is a crucial subject in the radiation protection field. Throughout this paper, an urgent and simple method was proposed for measuring 131I inside the pediatric thyroid gland by constructing a neck and thyroid phantom. For this purpose, CT scan images of healthy child's thyroids were obtained, and the sizes of different parts were determined by a 3D slicer image processing software. Girls with the body surface area between 0.95 and 1.05 were involved in this study. The fabricated phantom is composed of 5 cylindrical slabs of 2-cm thickness, and several small holes were constructed for TLD dosemeters near the thyroid gland and all other parts of the neck. The phantom was constructed utilizing a 3D printer with acrylonitrile butadiene styrene plastic. The thyroid phantom was filled with radioiodine-131, and calibration curves were plotted for contamination estimation. A nodular thyroid phantom was also constructed. The nodular phantom or the resolution phantom has 4 removable parts containing cylindrical holes with diameters of 3, 6, 9 and 12 mm. These holes on the thyroid glands can be filled with different activities of radionuclides to serve as hot and cold spots for quality control of nuclear medicine images. The results show that the designed phantom is applicable in different fields such as nuclear image quality and resolution tests, dosimetry and iodine thyroid uptake estimation in nuclear medicine departments, and nuclear emergency monitoring.

Artificial intelligence and radiation protection. A game changer or an update?

Artificial intelligence (AI) is regarded as one of the most disruptive technology of the century and with countless applications. What does it mean for radiation protection? This article describes the fundamentals of machine learning (ML) based methods and presents the inaugural applications in different fields of radiation protection. It is foreseen that the usage of AI will increase in radiation protection. Consequently, this article explores some of the benefits and also the potential barriers and questions, including ethical ones, that can come out. The article proposes that collaboration between radiation protection professionals and data scientist experts can accelerate and guide the development of the algorithms for effective scientific and technological outcomes.

Программный модуль оценки достижения радиологической эквивалентности (РОЗА-РАО)

The main problem of the large-scale development of nuclear energy in the world is the safe dis-posal of accumulated radioactive waste (RW). The hazard of RW at the time of their formation to human health far exceeds the hazard of the source natural uranium ore, after the use of which these wastes were formed. Due to the natural processes of radioactive decay, the hazard of radi-oactive waste decreases over time. The hazard of waste can also be reduced by artificial trans-mutation or incineration of the radionuclides that make up RW composition. For uranium nuclear fuel cycles, the natural reference level of RW hazard is the hazard level of the uranium ore, upon reaching which decisions can be made on the final disposal of RW. The article presents a meth-od for estimating the time of achieving radiological equivalence of the mass of accumulated RW of nuclear energy and the source mass of natural uranium raw materials used in this case. A de-scription of the software module "Radiological support of protection – radioactive waste" (PM ROZA-RAO), which implements this method, is also presented. Radiological equivalence herein refers to the equality of the corresponding radiation risks for the population. The methodology used is determined by the current recommendations of the International Commission on Radio-logical Protection (ICRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) on the calculation of human radiation risks from internal exposure based on equivalent doses in organs and tissues. The determination of equivalent doses to organs and tissues was based on dose coefficients of radioactive substances provided for widespread use by the United States Environmental Protection Agency (EPA). Calculations by means of the PM ROZA-RAO showed that within the framework of the most likely scenario for the development of two-component nuclear energy system in Russia, for radioactive waste accumulated by 2100, the time of onset of radiological equivalence is less than 100 years (98.8 years). With the help of the developed software module, for the first time in the nuclear industry, the parameters of the processing of exposed nuclear fuel (the composition and activity of radionuclides for controlled storage, combustion and transmutation) and the management of RW can be determined, minimizing the potential radiation risks of the population, which corresponds to the best practice of developed countries in the field of radiation protection.

RadoNorm – towards effective radiation protection based on improved scientific evidence and social considerations – focus on RADON and NORM

RadoNorm aims to manage risks from exposures to radon and naturally occurring radioactive material (NORM) to promote effective radiation protection based on improved scientific evidence and social considerations. It supports the European Member States and the EU Commission (EC) in implementing the Basic Safety Standards for protection against ionising radiation hazards at the legislative, executive, and operational levels (Directive 2013/59/EURATOM). The project is grounded on (1) implementation of multidisciplinary and innovative research and technologies, (2) integration of education and training, and (3) dissemination of project results targeting a broad stakeholder community including the public, regulators, and policymakers. The objectives are achieved through scientific research-related topics (exposure, dosimetry, biology, epidemiology, societal aspects), cross-cutting topics (education and training, dissemination, ethics) and project management. The project will yield guidelines at legal, executive and operational levels. It will enable consolidated and harmonised decision-making in the field of radiation protection, considering societal aspects and sustainable knowledge transfer. The project contributes to EC activities to strengthen radiation protection in a consistent and joint manner, as has already been done through the establishment of radiation protection platforms, the promotion of projects (e.g., DoReMi, OPERRA) and the partnership CONCERT-EJP. The outcomes may also impact future recommendations.

The Recent Points in the Field of Radiation Protection: Radiation Safety Culture and Emergency Monitoring

The Recent Points in the Field of Radiation Protection: Radiation Safety Culture and Emergency Monitoring

Physical, structural and nuclear radiation shielding behaviour of xBaO-(0.30-x)MgO-0.10Na2O-0.10Al2O3-0.50B2O3 glass matrix

In the present investigations, six cylindrical shaped glass sample having chemical composition x BaO-(0.30-x) MgO-0.10Na2O-0.10Al2O3-0.50B2O3 (x = 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30 mol fraction) were prepared by melt quenching technique. The density, molar volume, oxygen packing density (OPD), oxygen molar volume (OMV), Poisson's ratio, barium inter ionic distance, Polaron radius and field strength were calculated for the prepared glass samples. The values of linear attenuation coefficients (LAC) were measured experimentally by using narrow beam transmission geometry in the gamma photon energy range of 59.54–1332 keV. In order to ascertain the application of the prepared glasses in the field of radiation protection and design, the values of LAC were used to calculate various gamma ray interaction parameters namely half value layer (HVL), Radiation Protection Efficiency (RPE), Mass Attenuation Coefficient (MAC), effective atomic number (Zeff), electron density (Ne) and Exposure Buildup Factors (EBFs). The values of fast neutron removal cross sections (∑R cm−1) were also calculated for the prepared glass matrix. The theoretical values of attenuation parameters were determined using online software Phy-X/PSD and FLUKA (Monte-Carlo) simulation code. Excellent agreements have been observed between experimental, theoretical and simulation results for the prepared glass samples. Furthermore, the radiation shielding properties for the prepared glass samples were compared with conventional used concretes and commercial radiation shielding glass (RS253 G-18). On the basis of the obtained results, it has been reported that the prepared glass samples possess satisfactory physical reliability and superior shielding efficiency against gamma rays and fast neutrons as compared to conventional/commercial shielding materials.

Assessing radiation risk perception by means of a European stakeholder survey

It is increasingly recognised that stakeholder views can be essential for ascertaining the credibility of those entrusted with protection of the public and workers against radiation risks, the robustness of the approaches to protection and the relevance of research underpinning radiation protection (RP). The CONCERT European Joint Programme of RP research included consideration of stakeholder views. These were evaluated by means of a publicly available survey, translated into 15 languages, to encourage responses from a wide range of European countries. The survey ran in 2017 and received some 1961 responses from many countries, although response rates varied widely between countries. The survey respondents were largely highly educated, with many having a professional connection to RP or the use of radiation in medicine or industry. Survey results indicated a high level of scientific/technical knowledge relevant to RP and indicated a general trust of most actors involved in the RP field, perhaps unsurprisingly given the nature of the sampled population. Most expressed a reasonable level of satisfaction with the information available to them on radiation risk, but there is clearly room for improvement. Additionally, the survey identified potential training needs amongst the groups who responded. It is concluded that, while the survey results are limited by the non-representativeness of the respondents by comparison with the population of the European Union as a whole, it has been successful in gaining insights into areas where communication could be improved, where professional training gaps are present and where research could help to build wider trust in RP.

Joint Environmental Radiation Survey by JAEA and KAERI Around the Fukushima Daiichi Nuclear Power Plant: Performance of Mobile Gamma-Ray Spectrometry Using Backpack and Carborne Survey Platforms.

According to the implementing arrangement between the Japan Atomic Energy Agency (JAEA) and the Korea Atomic Energy Research Institute (KAERI) in the field of radiation protection and environmental radiation monitoring, a joint survey program was performed to assess ground deposition of radioactive cesium in areas surrounding the Fukushima Daiichi Nuclear Power Plants. The purpose of this joint survey was to evaluate the field applications of the developed survey systems and methodologies. Understanding the performance of each system within a cesium-deposited contaminated zone is important for ensuring an appropriate response following a nuclear accident. The results of the measured ambient dose rates determined using each survey method were compared. Two kinds of survey system were used in the mobile gamma-ray spectrometry, which were MARK-M1 (Monitoring of Ambient Radiation of KAERI-the 1st Multipurpose system) based on two LaBr3(Ce) detectors of KAERI and KURAMA-II (Kyoto University Radiation Mapping - II) system with one CsI(Tl) detector of JAEA. First, mobile gamma-ray spectrometry using a backpack survey platform was conducted to assess the distribution of dose rates around specific survey sites, which were expected to be slightly contaminated by radioactive cesium in Minamisoma and Tomioka. A carborne survey using two gamma-ray spectrometers loaded inside a vehicle was successfully conducted to compare the measured dose rates in routes from site to site and verify evaluation methods, including attenuation correction.

Evaluation of the Correction Methods Using Age and BMI for Estimating CT Organ Dose Using a Radiophotoluminescence Glass Dosimeter and a Monte Carlo-based Dose Calculator.

The size-specific dose estimates (SSDE) have been recommended to replace the volume computed tomography dose index (CTDIvol) because it takes patient size into account. On the other hand, organ dose is thought to be a more appropriate quantity in the radiation protection field due to its correlation with radiation risk. The web-based computed tomography (CT) dose calculator WAZA-ARIv2 only offers organ doses for adults with four different body shapes and for children with five different ages. Since the American Association of Physicists in Medicine (AAPM) offers the conversion factors for SSDE and the correlation of SSDE with organ dose has been demonstrated, implementation of the conversion table might improve the accuracy of WAZA-ARIv2. This study aimed to evaluate a body mass index (BMI)-based and age-based correction method for estimation of the organ dose by using a radiophotoluminescence dosimeter (RGD), an anthropomorphic phantom, and the dose calculator WAZA-ARIv2. RGDs were individually calibrated by using an ISOVOLT TITAN-320 x-ray generator. The ratio of the SSDE conversion factors (CFSSDE) was used as the comparison index. For the BMI-based correction method, the ratio of CFSSDE values for the adult phantoms was expected to be 1.065, and the average ratio of the organ doses for the adult phantoms was 1.163 ± 0.169. For the age-based correction method, the ratio of CFSSDE value for 5- and 10-y-old pediatric phantoms was expected to be 0.889, and the ratios of the organ doses were 0.866 ± 0.024 and 0.909 ± 0.047 for the WAZA-ARIv2 dosimetry system and RGD dosimetry system, respectively. In conclusion, both evaluations of the experimental results showed the consistency between WAZA-ARIv2 and the SSDE conversion factor table. Moreover, the importance of taking the measurement position into account when applying the mass attenuation coefficient was demonstrated according to this study.

The role of radiation protection societies in tackling the skills shortage and development of young professionals and researchers

Over the last 10 years there have been increasing concerns raised about a potential skills gap in the field of radiation protection (RP). Noting these concerns in 2019, the Society for Radiological Protection, the UK’s Chartered Professional Body, launched a study to determine the RP demand in the UK going forward along with the capacity of the profession. The initial results show that over 50% of the SRP membership retires in the next 10−15 years, coupled with an increase in RP demand across the nuclear fuel cycle, medical sector and advancement of new technologies or applications requiring RP advice. This provides strong evidence supporting the concerns of a future skills gap. This paper presents a framework highlighting three core objectives that need to be met to resolve the skills gap. A review of the existing initiatives being undertaken by the Society of Radiological Protection to meet these objectives is included, identifying both areas of good practice and areas for further work and development. A key theme in tackling this challenge has been identified as the need to foster greater collaboration between RP professionals, and organizations both within the UK and abroad, such as IRPA, national societies, employers, academia and industry. This brings a unique opportunity to direct efforts and resources toward a common goal, allowing the sharing of good practice, whilst reducing the strain and burden on any one organization. Another key output of the review was the need to embrace new and innovative solutions to developing our profession and importantly inspiring and communicating into the future of the profession.

Estimation of the 234U fraction and uncertainty of enriched and depleted uranium

This paper provides a simple model for estimating the 234U fraction and uncertainty for enriched and depleted uranium produced by modern commercial gaseous centrifuge enrichment plants. Accurate estimation of the 234U fraction of uranium has applications to the nuclear engineering fields of radiation protection, nuclear materials measurement, transportation safety, criticality safety, and safeguards. Significantly, the 234U fraction and uncertainties drive radiation safety limits and dose estimates related to uranium and uranium facilities (excluding recycled uranium).

Utilisation of Moon Regolith for Radiation Protection and Thermal Insulation in Permanent Lunar Habitats

In the context of a sustainable long-term human presence on the Moon, solutions for habitat radiation and thermal protection with regolith are investigated. Regolith compression is studied to choose the optimal density-thickness combination in terms of radiation shielding and thermal insulation. The applied strategy is to protect the whole habitat from the hazards of galactic cosmic rays and design a dedicated shelter area for protection during solar particle events, which eventually may be a lava tube. Simulations using NASA’s OLTARIS tool show that the effective dose equivalent decreases significantly when a multilayer structure mainly constituted of regolith and other available materials is used instead of pure regolith. The computerised anatomical female model is considered here because future missions will be mixed crews, and, generally, more sex-specific data are required in the field of radiation protection and human spaceflight. This study shows that if reasonably achievable radioprotection conditions are met, mixed crews can stay safely on the lunar surface. Compressed regolith demonstrates a significant efficiency in thermal insulation, requiring little energy management to keep a comfortable temperature inside the habitat. For a more complete picture of the outpost, the radiation protection of lunar rovers and extravehicular mobility units is considered.

Influence of the type of salt-forming acids on the antiradiation activity of T1023 analogs – salts of N-isobutanoyl-S-isopropylisothiourea

According to leading experts, the vast arsenal of radioprotective agents available in the world today does not fully meet modern practical needs, both in the field of radiation protection, and in the prevention and treatment of complications of radiotherapy. The purpose of the study was to evaluate the effect of the salt-forming acids type on the radioprotective activity of NOS inhibitor T1023. The chemical part of this study included methods of chemical synthesis, physicochemical and elemental analysis. Pharmacological part – assessment of acute toxicity using V.B. Prozorovsky express method and the study of radioprotective activity using Till and McCulloch method based on the ability of mice hematopoietic cells to form spleen colonies after irradiation. The number of endogenous hematopoietic spleen colonies were assessed on the 8th day after total exposure to gamma-irradiation at a dose of 6 Gy in six independent experiments. As a result of directed chemical synthesis, six new derivatives of T1023 – salts of N-isobutanoyl-S-isopropylisothiourea have been developed, identified and characterized. The results of studying the safety and radioprotective activity of the synthesized compounds showed that changes in the salt-forming acid don’t significantly influence the toxicity: all studied compounds are in the 3rd class of toxicity and hazard. At the same time, it was found that the replacement of the salt-forming acid significantly influenced the severity of the radioprotective effect. For some of these compounds radioprotective efficacy is comparable to or exceeds the efficacy of the initial compound T1023. It is important to note that these new compounds were used in lower, more save doses than T1023. The results suggest promising further development of NOS inhibitors – isothiourea derivatives as radioprotective agents.

Confirm Suitability of the 3D Positive Ion Detector to Use in the Field of Radiation Protection, and Gamma Spectrometry Applications

It is well known that the environmental radiation surrounding us consists of various types of radiation that could be dangerous to human health, causes air pollution and also has importance in industry and medicine. There are different types of gamma spectrometry and radiation protection technologies are available. Even though these technologies have been used for several decades; there is a need to improve the sensitivity and selectivity for these detectors. The Multilayer PCB technology based Nanodosimeter was designed to capture positive ions produced by the interaction of ionizing radiation with low pressure gas medium. In order to confirm the signal, the present signal captured under methane medium at 1 to 10 Torr pressure. The indigenously fabricated 3D positive ion detector of thickness 3.483 mm with optimized cathode was using the same Nanodosimeter experimental setup using the Co-60 source. To conform the performance of the 3D positive ion detector as gamma spectrometry and Radiation protection.