Health physics最新文献

Radiation exposure in the catheterization laboratory poses a significant occupational hazard for primary operators. This single-center, open-label, randomized controlled trial conducted at Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, evaluated scattered radiation exposure to the primary operator during procedures via radial, femoral, and pectoral vascular access sites and the effectiveness of radiation protection drapes in reducing this exposure. A total of 216 patients (72 in each vascular access group) were randomized using coin flipping to receive either standard radiation protection or additional shielding with a radiation protection drape. The primary operator's scattered radiation dose was assessed in comparison to the radiation emitted during the procedure, with normalization to procedural radiation parameters including air kerma (AK), dose area product (DAP), and cine-adjusted screen time (CAST). Pectoral access was associated with the highest operator exposure (96.75 µSv) compared to femoral (45.72 µSv) and radial (49.06 µSv) access, despite lower AK values. Radiation protection drapes significantly reduced operator exposure across all access sites, with radial access showing reductions of 51% (DAP), 48% (AK), and 53% (CAST); femoral access showing reductions of 82% (DAP), 74% (AK), and 63% (CAST); and pectoral access showing reductions of 62% (DAP), 49% (AK), and 52% (CAST), all statistically significant (P < 0.05). No adverse events were reported. The findings provide strong support for the routine use of radiation protection drapes to minimize primary operator radiation exposure during catheterization procedures, especially when using the pectoral access site.

The principle of justification is intended to ensure the net benefit of a proposed activity that would alter radiation exposure. While the concept is simple and easy to understand, its application, including the basis for judgments and the process for reaching a decision, is not straightforward. It has been demonstrated in the last decades that the decision-making process in radiological protection and safety requires not only scientific and technical rationality but also consideration of stakeholder views to appropriately reflect societal and ethical values. In view of these emerging challenges, the International Commission on Radiological Protection created Task Group 124 for the purpose of revisiting and modernizing the principle of justification. The Task Group collected various views and opinions of radiation protection experts through an online workshop and an international conference. They were examined to identify areas that need further clarification and to extract ideas that were not given sufficient consideration in the past. The Task Group is working to compile a report that identifies essential elements and key perspectives in the decision-making process for justification. It aims to clarify what "do more good than harm" means in society today and on what basis the judgment should be made.

Emergency responders and health physicists need to make quick decisions on initial analyses and observations when responding to a radiological or nuclear emergency. Health physicists use complicated mathematical equations and dose calculation algorithms to create precise and detailed dose reconstructions, but this is dependent upon the release of information regarding the exposure or contamination scenario. The Radiation Emergency Assistance Center/Training Site employs and teaches certain "rules of thumb" dose estimation techniques for both internal and external exposures, which may help in early phase dose reconstruction and for predicting health outcomes by health care providers. This includes using the point source equation and inverse square law to estimate a person's exposure from a source at a given distance, assessing internal inhalation intakes, and estimating internal deposition based on initial uptake measurements from wound or nasal contamination. Biodosimetry techniques can be used to estimate the absorbed dose, with dicentric chromosome assay being the gold standard. Other biodosimetry techniques include evaluating symptoms of acute radiation syndrome and cutaneous radiation injury. The intent for these initial dose reconstruction techniques is not to replace the existing dosimetry techniques but to allow rapid initial patient triage, so that life-saving interventions may be employed immediately.

This paper summarizes the presentations and panel discussion provided at Plenary Panel #2 on the first day of the 16th World Congress of the International Radiation Protection Association (IRPA) jointly organized with the 69th Annual Meeting of the Health Physics Society (HPS) in Orlando/Florida in July 2024. International organizations that play a key role in radiation protection and are close in contact with IRPA by official agreements or even MoU's (Memorandum of Understanding) presented highlights of their projects in radiation protection as well as results. Topical issues on their current work program as seen in a list of statements, including future efforts, were presented and discussed. The needs of practitioners were stressed for recognition by the representatives of the international organizations to be included in their projects. Requested and presented topics were: • Key challenges for radiation protection practitioners in the next 10 y. • Potential effects of emerging science on radiation protection. • Challenges for implementation of IAEA Safety Standards in low- and middle-income countries. • Challenges in occupational radiation protection. • Broadening the process of optimization. • Impact of emerging technologies on radiation protection. • Ensuring radiation protection workforce for the future.

In the case of an emergency exposure situation, in addition to the immediate measures to stop the release, there is also a need for measures to analyse the potential intakes of radionuclides among emergency personnel and the directly affected population. This catalogue of requirements could serve as a basis for the development of regulations in the event of emergency exposure situations and intends to refer, in particular, to the responsibilities and tasks, an estimate of the material and personnel requirements, and the metrological requirements. We present the catalogue that was developed by the working group "Monitoring of Intakes" of the German-Swiss Association for Radiation Protection taking into account German regulations.

Background: The study examined the levels of knowledge, awareness, and attitude toward medical radiation among patients, household members, and clinicians. The radiation knowledge gap among healthcare providers and the community may pose challenges to radiation safety, particularly regarding informed decision-making and adherence to radiation protection principles and safety culture.

Methods and materials: A quantitative cross-sectional study using a descriptive approach was conducted in Tanzania among clinicians, patients who were prescribed for radiological examination, and household members who did not visit hospital during data collection period. Participants were sampled using a convenient systematic method.

Results: Results revealed that both patients and household members had low knowledge and awareness about medial radiation. However, they demonstrated a strong positive attitude toward the use of radiation in medicine indicating trust in healthcare practices despite limited understanding. In contrast, clinicians showed high levels of knowledge and awareness highlighting their essential role safe and effective use of radiation as justification principles demand.

Conclusion: Improving public knowledge and awareness about medical radiation is essential to compliment the positive attitude observed and to enhance radiation safety practices in hospitals. Strengthening education and communication between healthcare providers and the community will play a vital role in promoting informed decision-making and ensuring effective radiation protection for all.

Experimentally measured nuclear fragment-production cross-sections are needed for the development of cross-section models implemented in the radiation transport codes used for several endpoints, including radiation protection and health risk assessment in space. Elemental and isotopic fragment-production cross-section data have been collected from literature in a publicly available database through a combined GSI-ESA-NASA effort. The collected data for systems of interest for space exploration are discussed, and the literature gaps are indicated. The data are also compared with the nuclear fragmentation models implemented in the NASA radiation transport code HZETRN2020, namely NUCFRG3 and RAADFRG. The results show that NUCFRG3 does not take into account nuclear-structure effects, while RAADFRG does. Therefore, RAADFRG can estimate more precisely the production of certain projectile fragments, in particular helium. Nevertheless, for some systems and high energies, RAADFRG overestimates the oscillations due to odd-even effects.

With the ICRP Publication 137 dealing with the occupational intake of radionuclides, an important and crucial path toward the practical implementation of the dosimetric approach also for radon was undertaken. However, some problems and difficulties must be overcome to use this new method to estimate the effective dose of radon in real situations. Direct dosimetric calculations are often not an easy task. The ICRP Publication 137 gives some examples of this new approach by providing the coefficients of the effective dose per exposure for some typical workplaces. In this work, some practical examples of the effective dose calculation in some selected workplaces were performed, studying the most important factors affecting the results. In particular, the role of the equilibrium factor F and of the dose conversion factor (DCF) as a function of the particulate size distribution were investigated and discussed. In this context, a few direct measurements of the equilibrium factor F were done as well as an experimental supporting tool for a comprehensive dose assessment.

Nuclear reaction cross-sections are needed for Monte Carlo and deterministic radiation transport codes used for ion therapy and radiation protection in space. A GSI-ESA-NASA combined effort generated a free and publicly available nucleus-nucleus reaction cross-section database. Nevertheless, protons - the main component of solar particle events and galactic cosmic ray fluences in space - account alone for over 60% of the effective dose behind thick shields in space and are used in 88% of the cancer-treatment ion-therapy centers worldwide. Therefore, in the present work, proton-projectile data have also been included. These data are compared to the reaction cross-section models used in radiation transport codes, including the models of Tripathi-Cucinotta-Wilson, Hybrid-Kurotama, Kox, Shen, and Kox-Shen. The Tripathi-Cucinotta-Wilson model uses the Tripathi99 model for low-Z projectile ions and the Tripathi96 model for other projectiles. The Hybrid-Kurotama model is based on the Black Sphere formula at high energies, which, for proton data, is smoothly connected to the Tripathi99 model at low energies. It is found that the Tripathi99 and Hybrid-Kurotama models best fit the proton-projectile data.