Journal of Radiological Protection最新文献

Personal radiation protective equipment (PRPE) play a critical role in minimizing occupational exposure to ionizing radiation in medical imaging, nuclear medicine, interventional procedures and related fields. Over time, repeated use, mechanical stress, and improper handling can degrade their protective performance, making regular inspection essential to ensure continued radiation safety. This study aimed to compare the performance of multiple imaging modalities in evaluating the integrity and lead equivalence of PRPE, to identify the most accurate and practical methods for quality assurance programmes. Over a four-year period, 1063 PRPE items from 20 manufacturers were evaluated. Each item underwent visual and tactile inspection, followed by imaging using radiography, fluoroscopy, computed tomography (CT), and a dedicated PRPE testing system (FLOWD 8020). Lead equivalence was determined by comparison with certified reference lead foils using both X-ray quality assurance dosimeter and image-based methods. Integrity was categorized on a four-level scale according to defect size and location, and attenuation performance was assessed relative to manufacturers' nominal specifications. Of all PRPE items tested, 88.8% were defect-free, while 11.2% showed cracks or tears cracks or tears of varying extent. Lead equivalence results revealed that 74.3% met specifications within ±5%, 13.8% deviated by 5-10%, and 11.9% by more than 10%. All imaging modalities demonstrated comparable accuracy, though the dedicated screening system offered clear advantages in workflow efficiency, full-apron coverage, automated reporting, and low stray dose (<0.3 μSv/h at 1 meter). Routine PRPE inspection is essential for maintaining occupational radiation safety. Standardized testing protocols and inspection intervals are recommended to ensure consistent and traceable quality assurance practices across institutions.

Neutron dose assessment in radiation accidents relies on measuring induced ²⁴Na activity via the ²³Na(n,γ)²⁴Na reaction. However, the effect of body size on neutron moderation, gamma self-absorption, and organ distribution-remains poorly quantified, with conflicting literature reports. To systematically evaluate the body size effect on neutron absorbed dose and ²⁴Na yield, four human voxel phantoms of different body sizes (5-, 10-, 15-, and 38-year-old individuals) were irradiated in MCNP simulations with ²⁵²Cf and 28 monoenergetic neutron sources (10-9 - 20 MeV) under six geometries. The neutron absorbed dose, induced ²⁴Na activity per unit mass, and the conversion coefficients between 24Na activity per unit mass and neutron absorbed dose were calculated. The results show that body size significantly affects the neutron dose. When the human body is irradiated with ²⁵²Cf neutrons under different irradiation geometries, the conversion coefficients between ²⁴Na activity per unit mass and neutron absorbed dose are at least 48.3% larger in adults than in 5-year-old children. When the human body is irradiated with monoenergetic neutrons under ISO irradiation geometry, these conversion coefficients decrease with increasing body size for neutron energies < 0.1 MeV, and increase with increasing body size for neutron energies > 0.1 MeV. For 10-9 MeV neutron irradiation, the coefficient for adults is 26.5% smaller than that of 5-year-old children. Conversely, for 20 MeV neutron irradiation, the coefficient for adults is 114.2% larger than that for 5-year-old children.

Protecting medical personnel from the harmful effects of scattered ionising radiation during x-ray-guided procedures is a critical concern. Due to the complex and invisible nature of x-rays, monitoring radiation exposure has been challenging. Existing real-time dosimeters have shown low accuracy and practical limitations. To address these challenges, this study introduces an innovative approach that combines Monte Carlo (MC) simulations and deep learning (DL) for real-time estimation of three-dimensional (3D) scattered radiation in the operating room. The neural network was trained to map patient morphology and imaging parameters to radiation maps, allowing it to adapt to various clinical scenarios. The results demonstrate that the system showcases exceptional speed by efficiently computing 3D radiation maps in 11 ms using modern GPU (NVIDIA RTX 2080). Validation experiments confirmed the reliability of the predicted scatter maps, with a mean absolute percentage error of 10.97% relative to MC simulations. When used to compute organ doses via voxelised-source simulations, the global average organ dose error was 8.2 ± 4.1%. Therefore, the combination of MC simulations and DL provides a promising solution for enhancing the safety of medical personnel during x-ray-guided procedures.

The Fire Rescue Service of the Czech Republic is a key component of the integrated rescue system, ensuring the protection of the population, the environment, and property from the effects of fires, chemical accidents, and radiation incidents. Given the changing security situation in Europe and growing technological demands, it is necessary to analyse the preparedness and activities of members of the Fire Rescue Service of the Czech Republic in the area of chemical services and radiation protection. The aim of the study was to evaluate the current state of professional training, equipment, and ethical aspects of interventions, and to propose measures to increase the effectiveness of the system. Methodologically, the work is based on qualitative research of professional literature and evaluation using SWOT analysis, which identifies the strengths and weaknesses of the system, opportunities, and threats. The results show that the Fire Rescue Service of the Czech Republic has a robust training system and technical facilities, but faces challenges in the areas of integrating new technologies, the mental resilience of responders, and ethical decision-making. The study recommends expanding training to include augmented reality simulations, supporting research into environmentally friendly shielding materials, and introducing ethical protocols for interventions in contaminated environments.

The differences in risk perception between women and men regarding the health effects of radiation following nuclear disasters are well documented. In particular, after the 2011 Fukushima accident, mothers with young children exhibited higher levels of risk perception and a greater tendency toward prolonged depression. However, the broader social context underlying women's heightened depressive symptoms has received little attention. To address this gap, this study analyzed the publicly available 2014 records of the ICRP Fukushima Dialogue-a stakeholder meeting held in Fukushima Prefecture-focusing on discussions about child-rearing and the dynamics of participant interaction. The analysis revealed that women with young children in Fukushima were subject to strong normative expectations. While these expectations were often experienced as a burden, the women also internalized them and took on the responsibility of motherhood as their own. Such expectations simultaneously constrained women's capacity for independent social action and demanded that they protect their children from radiation exposure. This contradiction-being expected to meet both demands at once-constitutes a double bind. The findings indicate that, in the aftermath of the accident, women with young children in Fukushima were indeed caught in such a situation, shaped by the prevailing social context.

Disasters have a wide range of effects on society. Nuclear disasters require a multifaceted response that considers the direct health effects of radiation exposure and indirect health consequences associated with evacuation. In recent years, the development and evaluation of practical nuclear disaster preparedness measures have become critical challenges for regions hosting nuclear power plants due to the growing risk of increasingly complex natural hazards. This study aimed to clarify the operational challenges of radiation-shielded shelter facilities used for sheltering during disasters by investigating the damage sustained by such facilities in Shika Town, Ishikawa Prefecture, where a seismic intensity of 7 was recorded during the 2024 Noto Peninsula Earthquake. The study was conducted through interviews and analysis of official damage reports by the Cabinet Office, targeting 12 radiation-protective facilities equipped with positive-pressure systems located within the Precautionary Action Zone (PAZ) and the Urgent Protective Action Planning Zone of the Shika Nuclear Power Plant. The results identified two major operational issues: (1) a lack of shared understanding regarding the target pressure differentials for positive-pressure systems and (2) a decline in building airtightness due to structural damage caused by the earthquake. In addition, insufficient sharing of knowledge and operational criteria between administrative authorities and on-site personnel has emerged as a challenge for the practical use of these facilities. These findings underscore the need for standardised criteria for seismic resistance and airtightness that assume the occurrence of compound disasters, as well as the importance of strengthening information-sharing systems during normal times. Furthermore, the study highlights that even within the PAZ, older individuals and persons requiring special care may face difficulties in executing immediate evacuation, potentially making sheltering-in-place the only feasible option. Therefore, it is necessary to reconsider the institutional position of sheltering as a realistic form of evacuation.

Radiation exposure to the fingers of clinicians carrying out radiosynoviorthesis with yttrium citrate (⁹⁰Y) can be an area of concern if equipment or practice is sub-optimal, with contact dose rates in the mSv·s^-1range around the syringe and needle neck. Syringe shields reduce potential exposure around the syringe but offer no protection around the needle neck. There are no commercially available protection products in the United Kingdom to address this deficiency. Clinical safety requires that the clinician is able to feel the position of the needle and limit the amount of needle movement at critical times. Although direct handling of the needle neck presents the easiest solution, radiation protection concerns make this unacceptable, and leave forceps the only established alternative to minimise finger doses. We present a further method to address these issues-a locally designed infection control compliant finger protection ring which has been 3D printed and used at the authors' hospital. Potential extremity doses have been measured for three methods. 1, direct finger contact with the needle neck, 2, forceps, and 3, use of a 3D printed ring. Finger dose coefficients with the first method (direct contact) have been demonstrated experimentally to be as high as 33µSv·MBq^-1, with even higher results recorded in clinical practice at 79.5µSv·MBq^-1. The second method (forceps) reduces the potential skin dose coefficient to less than 1µSv·MBq^-1. The third method (finger protection ring) achieves a similar dose coefficient to forceps. Forceps are more technically demanding for the clinician. This new finger protection ring ensures that patient safety is maintained, the procedure is technically easier for the clinician, finger doses are as low as Reasonably Practicable, and contamination risk is reduced.

Breast tissue is highly sensitive to ionising radiation, making dose management in mammography crucial to reducing the risk of radiation-induced cancer. Dose optimisation, guided by the as low as reasonably achievable principle, aims to minimise exposure while maintaining diagnostic quality. This study focuses on establishing national diagnostic reference levels (NDRLs) for digital mammography (DM) in Nepal to support dose optimisation efforts. A retrospective analysis was conducted using data from 786 patients across six hospitals equipped with DM systems. Both symptomatic and screening mammograms in cranial-caudal (CC) and mediolateral oblique (MLO) views were included for both breasts. Mean glandular dose and entrance skin dose were extracted from Digital Imaging and Communication in Medicine headers. For each mammogram view, data from a minimum of 50 patients were analysed. Technical parameters such as tube voltage (kVp), tube current (mAs), compression force (CF), and compressed breast thickness (CBT) were also documented. The established NDRLs for DM are 1.03 mGy for CC and 1.17 mGy for MLO views. The mean CBT and CF are 56 ± 13 mm and 122 ± 29 N, respectively. Comparisons with other countries highlight the potential for further dose optimisation to maintain diagnostically adequate images at lower exposure levels. Implementing such strategies can reduce patient radiation dose in DM without compromising diagnostic performance.

Boundary-representation (B-Rep) computational phantoms (CPs) offer high flexibility and anatomical accuracy, making them valuable tools in dosimetry and medical imaging simulations. However, their complexity and the need for expertise in graphic modelling limit their accessibility and adoption. Moreover, most Monte Carlo (MC) particle transport codes lack native support for B-Rep geometries, requiring complex and non-automated conversion to compatible formats, further complicating their use. To address these challenges, we developed the interactive posture program (IPP), a software platform to ease the use of B-Rep phantoms. The IPP features a real-time three-dimensional (3D) graphical interface, allowing users to easily create individualised phantoms and realistic exposure scenarios. Currently, the IPP includes three flexible phantoms-Adult Male, Adult Female, and 1-year-old Female-from the realistic anthropomorphic flexible (RAF) family, which can be extensively customised using integrated morphing tools to simulate diverse anatomical variations. Additionally, the IPP provides a comprehensive library of predefined exposure scenarios and advanced geometry creation tools, which allow the creation of accurate and individualised simulations. Finally, the IPP automatically generates simulation input files compatible with the most widely used MC transport codes, significantly simplifying the use of B-Rep phantoms within dosimetry and imaging simulations.

The International Commission of Radiological Protection (ICRP) has made a review of the system of radiological protection toward a revision of general recommendations. The management of tissue reactions, previously known as deterministic effects, has always been a core aspect of the system of radiological protection. It is directly related to the health objectives of the system, which aims to prevent such effects. Tissue reactions, currently defined as 'injury in populations of cells characterised by a threshold dose and an increase in the severity of the reaction as the dose is increased further', are, in theory, prevented when dose remains below the threshold. This has significant implications for the system, including in relation to the setting of individual dose limits. This article reviews and discusses the approach proposed by the Commission with regards to the management of tissue reactions. It is based on the review of a set of relevant ICRP Publications, with the aim of contributing to the ongoing work on the review of the system of radiological protection.