Journal of Radiological Protection最新文献

{"title":"Model-based evaluation of point-source approximation error for extended radionuclide sources in nuclear medicine.","authors":"Rhodri Smith, Bill Thomson, Hannah Nelstrop, Anthony Murray","doi":"10.1088/1361-6498/ae8d2e","DOIUrl":"10.1088/1361-6498/ae8d2e","url":null,"abstract":"<p><p>Accurate estimation of external radiation exposure is essential in nuclear medicine (NM) for occupational safety and regulatory compliance. Point-source models are widely used because they are simple and require limited input data; however, their accuracy can degrade when radioactive material is distributed over extended line, surface, or volume geometries. This study evaluates point-source approximation error across a range of extended-source models, beginning with non-attenuating line and disc geometries and extending to attenuating finite-thickness slab and laterally viewed cylindrical volume sources. Absolute dose-rate examples were calculated using a Tc-99 m gamma constant, while relative error and correction-factor results were expressed using geometry- and attenuation-dependent parameters. For non-attenuating line and disc sources, point-source approximations can overestimate exposure by up to approximately 100% when source dimensions exceed the exposure distance. A practical threshold was identified: when the source dimension-to-distance ratio is less than one, point-source errors remain below 5%; above a ratio of 1, line or disc models should be considered or the point-source estimate corrected using the factors provided. For attenuating finite-thickness slab sources, an analytical correction factor was derived that separates into a lateral-extent term governed by the source diameter-to-distance ratio, and an attenuation-thickness term governed by. Together, these two dimensionless parameters allow point-source error to be mapped across combinations of source size, distance, attenuation coefficient and slab thickness. For laterally viewed cylindrical sources, kernel-based volume integration showed that point-source error depended jointly on,and, whereis the surface-to-point distance. The 20% error region narrowed markedly as, indicating that patient-scale attenuating cylinders cannot be assessed from distance alone. Representative Tc-99 m examples showed modest error for a 5 ml syringe-scale cylinder at 1 m, but substantial overestimation for a patient-torso-scale cylinder. Comparison with published measured patient dose-rate studies showed that the patient-torso cylindrical model produced values of a similar order of magnitude to measured 1 m patient dose rates, whereas point-source estimates were generally higher. This paper provides practical correction factors, error-threshold maps and model-selection guidance to support more appropriate selection of source models in NM exposure assessments.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148537560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Angular dependence of<i>H</i>_p(3): horizontal vs vertical rotation.","authors":"Rolf Behrens, Anna Camp Brunés, Arlene Cortés Balcells, Maria Amor Duch Guillén, Oliver Hupe","doi":"10.1088/1361-6498/ae955c","DOIUrl":"10.1088/1361-6498/ae955c","url":null,"abstract":"<p><p>This study investigates how much the conventional quantity value (true value) of the operational quantity<i>H</i>_p(3), defined in International Commission on Radiation Units and Measurements (ICRU) 47 and 51, changes for oblique radiation incidence when a rotation around the horizontal instead of the commonly used vertical axis of the cylinder phantom is performed. For this, conversion coefficients<i>h</i>_p<i>K</i>(3) and<i>h</i>_p<i>D</i>(3), for photons and betas, respectively, were calculated for both vertical (usual) and horizontal rotations of the cylinder phantom for mono-energetic photons from 2 keV to 10 MeV and for reference beta-particle fields with mean energies from 0.54 MeV to 1.2 MeV (and maximum beta energies from 1.4 MeV to 3.3 MeV). From the results, the ratio of the values for horizontal and vertical rotations were determined. To complement these, the corresponding ratios for the protection quantity equivalent dose to the lens of the eye,<i>H</i>_lens, defined in International Commission on Radiological Protection 116, were calculated and compared with the results for<i>H</i>_p(3). For photon fields most relevant in lens monitoring, i.e. especially in interventional radiology, it turned out that<i>H</i>_p(3) is only slightly (up to ∼10%) smaller when rotating around a horizontal instead of the commonly used vertical axis. Larger differences only occur for small photon energies (below ∼20 keV) and large angles of radiation incidence (75°) where<i>H</i>_p(3) is reduced to practically zero for a horizontal rotation compared to the normal (vertical) rotation. For reference beta-particle fields, the differences between vertical and horizontal rotations are also mostly below 10% - due to the rather broad angular distribution of the beta fields resulting in only small differences of the 'effective' path length in the cylinder phantom. In contrast, the differences of the dose to the lens of the eye,<i>H</i>_lens, are rather large for both photons and betas and always significantly larger than for<i>H</i>_p(3). From the author's point of view, these findings do not impose the necessity to update the<i>H</i>_p(3) by distinguishing between the (usual) vertical and a horizontal rotation axis. Nevertheless, the data presented may serve ICRU to judge whether an updated definition of the operational quantity<i>H</i>_p(3) should be considered. If so, International Standardization Organization needs to provide<i>H</i>_p(3) values for horizontal rotations of the cylinder phantom for reference radiation fields and International Electrotechnical Commission needs to extend their dosemeter type-test procedures to horizontal rotations.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148680439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Local diagnostic reference levels for paediatric computed tomography based on European guidelines: anatomy- and indication-based approaches.","authors":"Mariliis Tiidermann, Jaanika Paemre, Pille Kool, Mare Lintrop, Pilvi Ilves","doi":"10.1088/1361-6498/ae90b5","DOIUrl":"https://doi.org/10.1088/1361-6498/ae90b5","url":null,"abstract":"<p><p>Diagnostic reference levels (DRLs) guide dose optimisation, yet paediatric computed tomography (CT) DRLs remain scarce, heterogeneous, largely anatomy-based. This study aimed to establish local paediatric DRLs for head, chest, and abdomen-pelvis CT according to European guidelines, compare them with European DRLs, and assess the feasibility of indication-based DRLs. This single-institution study included 604 of 829 CT acquisitions performed in children aged ⩽16 years in 2017 or 2022. DRLs, defined as the 75th percentiles of volumetric CT dose index (CTDIvol) and dose length product, were derived by age for head CT and by weight for body CT. Indication-based DRLs were explored for five indications. Local DRLs were compared with European and other recent values using 95% confidence intervals. Quantile regression was used to estimate DRL curves and identify predictors for cervical spine CT dose. Head CT DRLs were up to 33% lower than European levels (<i>p</i>< 0.05), and abdomen-pelvis CT DRLs up to 44% lower (<i>p</i>< 0.05), while chest CT DRLs did not differ significantly (<i>p</i>> 0.05). Compared with recent studies, head CT DRLs were lower (<i>p</i>< 0.05), whereas chest and abdomen-pelvis CT DRLs were higher for some groups. Higher doses were observed with older scanner. DRLs for craniosynostosis and chronic sinusitis CT were tenfold lower than those for head trauma or stroke CT. For cervical spine CT, weight was a stronger predictor of CTDIvol than age (pseudo<i>R</i>²= 0.72 vs 0.54). In conclusion, paediatric CT DRLs can be established at institutional level in accordance with European guidelines. The observed DRLs suggest successful implementation of optimisation strategies for head, whereas chest and abdomen-pelvis CT may offer further optimisation potential. Latest-generation scanners and paediatric protocols across the paediatric spectrum should be standard practice, and greater emphasis on indication-based DRLs can enable more precise and clinically relevant optimisation. Weight-based stratification is recommended for cervical spine CT DRLs.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":"46 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148800811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A narrative review of cancer risks in medical radiation workers across high- and low-dose practice eras: implications for radiation protection.","authors":"Rex N Taibu, Lloyd M Mataka","doi":"10.1088/1361-6498/ae955b","DOIUrl":"10.1088/1361-6498/ae955b","url":null,"abstract":"<p><p>Medical radiation workers constitute the largest occupational group exposed to man-made ionising radiation, yet much of the evidence on cancer risk derives from early high-dose practice eras that differ substantially from contemporary conditions. This narrative review synthesises evidence from cohort studies of medical radiation workers across occupational exposure eras, with emphasis on epidemiologic approaches, observed cancer risk patterns, and sex-specific differences. Epidemiologic methods have evolved from proxy-based exposure indicators to quantitative dose-response modelling using excess relative risk, supported by improved dosimetry and organ-dose reconstruction. Early high-dose cohorts consistently demonstrate elevated risks for radiosensitive cancers, including breast cancer, haematopoietic malignancies, and non-melanoma skin cancer. In contrast, contemporary cohorts exposed under current protection standards accumulate low cumulative doses and show small, often non-significant dose-response estimates with wide confidence intervals. These findings reflect both reductions in occupational exposure and the limited statistical power of epidemiologic studies at low dose levels, where excess risks are difficult to detect and dose-response shape cannot be clearly distinguished. Available evidence does not indicate consistent sex-based differences in radiation-related cancer risk at occupational exposure levels. Overall, while advances in dosimetry have improved exposure assessment, the ability to quantify cancer risk under contemporary low-dose conditions remains constrained. The findings support the effectiveness of current radiation protection practices while highlighting persistent uncertainty in estimating risks at low occupational doses.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148680433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiological clearance at CERN: classical machine learning methods for waste classification.","authors":"A Gomes, M Magistris, M E Stamati, C Theis","doi":"10.1088/1361-6498/ae8d2f","DOIUrl":"10.1088/1361-6498/ae8d2f","url":null,"abstract":"<p><p>At CERN the maintenance and dismantling of high-energy particle accelerators generate waste that is potentially radioactive. When activity levels are negligible, waste can be released from regulatory control through clearance procedures. However, radiological characterisation is challenging due to the diversity of activation scenarios, radionuclide inventories, and material compositions. We address this complexity by developing a data-driven probabilistic approach that combines activation simulations with classical machine learning. This study applies the method to irradiated electric cables, with a particular focus on defining threshold values for measurable quantities (activity, dose rate, and mass) that determine clearance eligibility. The proposed method offers operational advantages by simplifying measurement and decision-making procedures and is consistent with international guidance on clearance.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148537520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Survey of safety practices of laser and non-laser optical radiation sources used in aesthetic laboratories in Greece.","authors":"Petri Aspasia, Karatsalioti Maria, Pilakouta Mirofora, Varvaresou Athanasia","doi":"10.1088/1361-6498/ae90b4","DOIUrl":"10.1088/1361-6498/ae90b4","url":null,"abstract":"<p><p>The use of non-ionising radiation for aesthetic purposes is steadily increasing, with aesthetic laboratories frequently employing lasers, intense pulsed light (IPL), ultraviolet, and light-emitting diode (LED) devices. In Greece, as in many countries, no regulatory framework exists to ensure the safety of clients and operators, despite international recommendations for harmonised oversight. This study aimed to document device use, safety measures, and operator knowledge in Greek aesthetic laboratories. An electronic questionnaire was distributed to the 964 members of the Federation of Professional Associations of Diplomated Aestheticians of Greece (O.S.E.D.A.E), with 120 responses (12.4%). Among the participants 91 of the them were scientific supervisors of a laboratory. Results showed that 85% of (the 91) aesthetic laboratories used lasers (12% more than one type), 50% used LED, and 33% employed IPL systems. Although few injuries were reported, approximately 60% of respondents lacked an accident protocol for lasers, and over 70% lacked one for IPL and LED. Furthermore, from the answers of all participants (120), indicated that safety measures were applied mainly for clients, while warning signage was often absent. Training on device use and safety was provided primarily by suppliers. Respondents identified equipment maintenance and operator training as the most important safety measures, and most of them expressed strong interest in further education. The findings highlight the need to strengthen the safety culture surrounding the aesthetic use of optical radiation in Greece.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148609591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of backscatter factor in ISO-recommended phantoms for photon beams of different beam sizes using Monte Carlo simulations.","authors":"Rohit Yadav, A K Bakshi, B K Sapra","doi":"10.1088/1361-6498/ae8e83","DOIUrl":"10.1088/1361-6498/ae8e83","url":null,"abstract":"<p><p>Backscatter factor (BSF) is a critical correction parameter in radiation dosimetry, accounting for dose enhancement due to photon scattering within irradiated media; however, systematic evaluations beyond the ISO slab phantom remain limited. In this work, BSFs were comprehensively estimated for all ISO-recommended phantoms-slab, cylindrical, pillar, and rod-over a photon energy range of 10 keV-2 MeV and multiple field sizes using the FLUKA Monte Carlo code with an air-kerma-based formalism. The results show a strong coupled dependence of BSF on photon energy and beam size, with a characteristic peak in the intermediate energy range (∼40-80 keV) and geometry-driven variations and field-size sensitivity-maximized in the slab phantom and minimized in the rod due to scattering volume constraints, while cylindrical and pillar phantoms exhibit intermediate behaviour. To extend these results to realistic irradiation conditions, a Python-based standalone tool was developed using PCHIP interpolation and fluence-weighted averaging to compute spectrum-averaged BSFs for ISO 4037 beams, diagnostic and therapeutic spectra, and user-defined spectra, demonstrating deviation within 0%-2.3% with published data. The study provides a BSF dataset across all ISO phantoms along with a validated computational framework, enabling improved accuracy in dosimeter calibration and determination of operational quantities such as<i>H</i>_p(3) and<i>H</i>_p(0.07). The Python-based standalone executable of the BSF software, compatible with both Windows and Linux platforms, along with its complete source code, is provided as open-access supplementary data.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148563384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The declaration of Adelaide white paper: guidelines for author responsibility in peer review<sup />.","authors":"Loredana G Marcu, Chris Clement, Anna Friedl, Richard Harbron, Werner Rühm, Magdalena Stoeva, Michael Thorne, Iuliana Toma-Dasu, Jamie Trapp, Andrzej Wojcik, Gayle Woloschak","doi":"10.1088/1361-6498/ae8270","DOIUrl":"10.1088/1361-6498/ae8270","url":null,"abstract":"","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148334101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whose occupational dose are we estimating?","authors":"Derek W Jokisch, Nicole E Martinez","doi":"10.1088/1361-6498/ae8afd","DOIUrl":"10.1088/1361-6498/ae8afd","url":null,"abstract":"<p><p>Occupational dosimetrists are asked to estimate and assign effective dose for radiation workers' dose of record. An informal poll taken at a recent International Commission on Radiological Protection (ICRP) virtual workshop suggests there may be confusion or misconceptions among those practicing in the field of radiation protection as to which dose(s) should be assigned to a worker's record as described, defined, and recommended by the ICRP. Multiple ICRP publications make clear that the effective dose assigned to a worker's record should be that which the Reference Person would theoretically receive if they received the same radiation exposure as the worker. This paper briefly reviews the basis for ICRP's recommendation regarding dose of record and discusses challenges that may result with certain departures from ICRP recommendations.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148457595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical justification for osteoporosis investigation: transitioning from opportunistic to diagnostic referrals from alternative forms of imaging.","authors":"Robert Meertens, Claire Senior","doi":"10.1088/1361-6498/ae8afc","DOIUrl":"10.1088/1361-6498/ae8afc","url":null,"abstract":"<p><p>Clinical justification remains fundamental to the safe use of imaging involving ionising radiation, requiring a favourable balance between diagnostic benefit and stochastic risk. Concurrently, advances in imaging technology and artificial intelligence have enabled opportunistic identification of additional pathologies beyond the primary indication for imaging. This opinion article discusses how emerging opportunistic osteoporosis detection technologies may eventually transition into clinically justified diagnostic pathways in their own right.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":"46 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148609527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}