{"title":"Activity estimates of localised gamma emitting radionuclides using a GR-135 survey meter.","authors":"Brian Bewer","doi":"10.1088/1361-6498/ad5a17","DOIUrl":"10.1088/1361-6498/ad5a17","url":null,"abstract":"<p><p>During the operation of high energy accelerators activated materials are commonly created. The activity and isotopes present in these materials must be characterised for their clearance and release from the facility, or to ascertain their duration of stay in a radiological storage area. An activity estimate method using a gamma detecting GR-135 survey meter, which has the ability to collect an energy spectrum, is presented. Using several reference radioactive sources the detection efficiency and dead time of the survey meter were characterised. This information combined with the physical properties of the survey meter, the counting time and the properties of the measured photon energy emissions can be used to calculate an accurate activity estimate for localised activation on accelerator components, or loose contamination on isolated waste materials.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141433251","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":"Designing an improved model of the adult female ICRP reference phantom dedicated to mammography procedure.","authors":"Atiyeh Ebrahimi-Khankook, Alireza Vejdani-Noghreiyan, Hamidreza Khodajou-Chokami, Zahra Abbasi-Khiabani","doi":"10.1088/1361-6498/ad455e","DOIUrl":"10.1088/1361-6498/ad455e","url":null,"abstract":"<p><p>Mammography is an x-ray-based imaging method to examine breast abnormalities. Since low-energy photons are used in mammography, doses to different organs would depend strongly on the phantom posture and anatomy. Until now, a few studies have been performed on doses delivered to different organs during mammography. However, in none of them, the correct posture of the patient has been considered. In the present study, the effect of accurate patient positioning, on doses to organs in the chest region were investigated through Monte Carlo simulations. The results show the rotation of the phantom head, may affect organ doses up to 60%. Also, ignoring the head in dosimetry calculations changes scattering effects and causes dose uncertainty of about 8% for these organs. Moreover, according to the obtained results, not compressing the breast causes serious dose misestimation. Finally, using developed phantoms dedicated for mammography, total doses received by different organs have been calculated for the tube voltages of 25, 28, 30 and 35 kVp and for craniocaudal and mediolateral oblique views.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140865620","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}
Daniel Santiago Rondón, Pasquale Lombardo, Mahmoud Abdelrahman, Lara Struelens, Filip Vanhavere, Niki Bergans
{"title":"Object and person tracking systems to enable extremity dosimetry in nuclear medicine using computational methods.","authors":"Daniel Santiago Rondón, Pasquale Lombardo, Mahmoud Abdelrahman, Lara Struelens, Filip Vanhavere, Niki Bergans","doi":"10.1088/1361-6498/ad53d5","DOIUrl":"10.1088/1361-6498/ad53d5","url":null,"abstract":"<p><p>Nuclear medicine (NM) professionals are potentially exposed to high doses of ionising radiation, particularly in the skin of the hands. Ring dosimeters are used by the workers to ensure extremity doses are kept below the legal limits. However, ring dosimeters are often susceptible to large uncertainties, so it is difficult to ensure a correct measurement using the traditional occupational monitoring methods. An alternative solution is to calculate the absorbed dose by using Monte Carlo simulations. This method could reduce the uncertainty in dose calculation if the exact positions of the worker and the radiation source are represented in these simulations. In this study we present a set of computer vision and artificial intelligence algorithms that allow us to track the exact position of unshielded syringes and the hands of NM workers. We showcase a possible hardware configuration to acquire the necessary input data for the algorithms. And finally, we assess the tracking confidence of our software. The tracking accuracy achieved for the syringe detection was 57% and for the hand detection 98%.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248842","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 Gaussian-plume based Monte Carlo method for calculating radiation dose in the near field of buildings.","authors":"D J Gallacher, A G Robins, P Hayden","doi":"10.1088/1361-6498/ad53d6","DOIUrl":"10.1088/1361-6498/ad53d6","url":null,"abstract":"<p><p>A Monte Carlo (MC) programme was written using the dose point kernel method to calculate doses in the roof zone of a building from nearby releases of radioactive gases. A Gaussian Plume Model (GPM) was parameterised to account for near-field building effects on plume spread and reflection from the roof. Rooftop recirculation zones and building-generated plume spread effects were accounted in a novel Dual Gaussian Plume (DGP) formulation used with the MC model, which allowed for the selection of angle of approach flow, plume release height in relation to the building and position of the release point in relation to the leading edge of the building. Three-dimensional wind tunnel concentration field data were used for the parameterisation. The MC code used the parameterised concentration field to calculate the contributions to effective dose from inhalation, cloud immersion from positron/beta particles, and gamma-ray dose for a wide range of receptor dose positions in the roof zone, including receptor positions at different heights above the roof. Broad trends in predicted radiation dose with angle of approach flow, release position in relation to the building and release height are shown. Alternative approaches for the derivation of the concentration field are discussed.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248712","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 difficulty of nuclear emergency prevention measures during natural disasters: ongoing challenges in Japan.","authors":"Momoka Yamamura, Yoshika Saito, Saori Nonaka, Toyoaki Sawano, Chihiro Matsumoto, Akihiko Ozaki, Chika Yamamoto, Tianchen Zhao, Hiroaki Saito, Makoto Kosaka, Toshiki Abe, Masaharu Tsubokura","doi":"10.1088/1361-6498/ad53d7","DOIUrl":"10.1088/1361-6498/ad53d7","url":null,"abstract":"<p><p>It is crucial to anticipate nuclear emergency scenarios and implement effective measures. Japan's climate and topography make it vulnerable to natural disasters; thus, it is necessary to address compounding and cascading disaster scenarios involving the simultaneous occurrence of natural and nuclear disasters. On 1 January 2024, an earthquake hit the Noto region of Ishikawa Prefecture, resulting in damage to the area around the Shika Nuclear Power Plant, located 90 km from the epicenter. This earthquake revealed that, in the event of a complex disaster, it is possible that residents living within 30 km of the Shika Nuclear Power Plant will be completely unprepared for a nuclear disaster. In the event of a complex disaster, it is crucial to implement appropriate countermeasures while balancing responses to both nuclear and natural disasters and optimizing radiation disaster prevention measures.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248780","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":"Comparison of linear energy transfer measurement for therapeutic carbon beam using CR-39 and TLD.","authors":"Zhou Yuan, Weihai Zhuo, Shiyan Yang, Zhiling Li, Jingfang Zhao, Bo Chen","doi":"10.1088/1361-6498/ad53d9","DOIUrl":"10.1088/1361-6498/ad53d9","url":null,"abstract":"<p><p>The measurement of linear energy transfer (LET) is crucial for the evaluation of the radiation effect in heavy ion therapy. As two detectors which are convenient to implant into the phantom, the performance of CR-39 and thermoluminescence detector (TLD) for LET measurement was compared by experiment and simulation in this study. The results confirmed the applicability of both detectors for LET measurements, but also revealed that the CR-39 detector would lead to potential overestimation of dose-averaged LET compared with the simulation by PHITS, while the TLD would have a large uncertainty measuring ions with LET larger than 20 keV<i>μ</i>m<sup>-1</sup>. The results of this study were expected to improve the detection method of LET for therapeutic carbon beam and would finally be benefit to the quality assurance of heavy ion radiotherapy.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248763","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}
Hiroshi Watabe, Peter K N Yu, Gary Tse, Dragana Krstic, Dragoslav Nikezic, M Rafiqul Islam, Zhanbing Wei, Yuezhou Wei, Mehrdad Shahmohammadi Beni
{"title":"Monte Carlo modelling of cyclotron and radioisotope center (CYRIC) at Tohoku University: a radiation protection study.","authors":"Hiroshi Watabe, Peter K N Yu, Gary Tse, Dragana Krstic, Dragoslav Nikezic, M Rafiqul Islam, Zhanbing Wei, Yuezhou Wei, Mehrdad Shahmohammadi Beni","doi":"10.1088/1361-6498/ad5450","DOIUrl":"10.1088/1361-6498/ad5450","url":null,"abstract":"<p><p>Protection against ionizing radiations is important in laboratories with radioactive materials and high energy cyclotron beams. The Cyclotron and Radioisotope Center (CYRIC) located in Tohoku University in Miyagi prefecture, Japan and is a well-known nuclear science laboratory with cyclotron beams and substantial number of high activity radioactive materials. Considering this, it is important to perform complete radiation transport computations to ensure the safety of non-occupational and occupational workers. In the present work, we have developed a complete 3-dimensional model of the main cyclotron building and radiation labs using Monte Carlo method. We have found that the dispersed photons and neutrons inside and in the surrounding of the CYRIC building pose no significant risk to occupational and non-occupational workers. The present work and the developed models would be useful in the field of radiation protection.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141262953","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}
E Vano, J M Fernández-Soto, R M Sánchez-Casanueva, J I Ten Morón
{"title":"Improving a regional project on diagnostic reference levels for interventional procedures (OPRIPALC) with the support of a dose management system for the protection of patients and staff.","authors":"E Vano, J M Fernández-Soto, R M Sánchez-Casanueva, J I Ten Morón","doi":"10.1088/1361-6498/ad53d8","DOIUrl":"10.1088/1361-6498/ad53d8","url":null,"abstract":"<p><p>Interventional radiology is a clinical practice with important benefits for patients, but which involves high radiation doses. The optimisation of radiation protection (RP) for paediatric interventional cardiology is a priority for both patients and staff. The use of diagnostic reference levels (DRLs) has been proposed by the International Commission on Radiological Protection to improve RP in imaging procedures. Dose management systems (DMSs) allow the automatic collection of dosimetric, geometric and technical data to assist the optimisation process, with a continuous audit of the procedures, generating alerts to implement corrective actions when necessary. Patient dose indicators may be analysed individually and for different radiation events (fluoroscopy and cine runs). Occupational doses per procedure may be analysed (if electronic dosimeters are available) and linked with patient doses for an integrated approach to RP. Regional optimisation programmes require data collection and processing from several countries to set and periodically update the DRLs. Patient data is anonymised, and each participating hospital has access to their data in a central computer server. Using DMSs may be one of the best ways to support these programs in the collection and analysis of data, raising alerts about high patient and occupational doses and suggesting optimisation actions.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248838","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":"Commissioning of the first hospital-based PET radiopharmaceutical cyclotron in Greece: personnel dose assessment.","authors":"S P Ioannidou, M Katsouli, E Doika","doi":"10.1088/1361-6498/ad460c","DOIUrl":"10.1088/1361-6498/ad460c","url":null,"abstract":"<p><p>The role of<sup>18</sup>F-fluoro-deoxy-glucose in positron emission tomography (PET) imaging is well established in diagnosis and management of cancer patients. Installations of on-site self-shielded mini cyclotrons are increasing. The Dose on Demand Biomarker Generator BG-75 was installed at Metaxa Cancer Hospital, Greece, in May 2021 and is the first hospital-based PET radiopharmaceutical cyclotron in the country. Personnel expected external exposure was established during commissioning; internal exposure is not expected. Personnel dose was estimated with two methods: survey meter measurements in various locations combined with the time spent in each location, and direct measurement using electronic personal dosemeters. Gamma and neutron radiation readings outside the cyclotron vault were at background levels. Inside the cyclotron vault, the highest recorded radiation readings by the target were 18<i>μ</i>Sv h<sup>-1</sup>for both gammas and neutrons with cyclotron in operational mode; at one meter, the values were 5<i>μ</i>Sv h<sup>-1</sup>and 4<i>μ</i>Sv h<sup>-1</sup>, respectively. The annual expected whole body dose per cyclotron operator is 0.6 mSv, and the respective extremity dose 16 mSv. The annual expected whole body and extremity dose for the radiochemist is 0.3 mSv and 25 mSv, respectively. The respective annual dose estimates for the medical physicists are < 1 mSv. The expected personnel doses are well below the regulatory limits and local as low as reasonably achievable (ALARA) levels. With experience and a robust ALARA program, personnel exposure could be further reduced.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140871073","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":"Statistical evaluation of individual external exposure dose of outdoor worker and ambient dose rate at evacuation ordered zones after the Fukushima Daiichi Nuclear Power Station accident.","authors":"Motofumi Saisu, Tadahiko Ando, Keizo Uchiyama, Toshihiro Ueno, Koichi Takizawa, Yuji Endo, Kazuya Yoshimura, Yukihisa Sanada","doi":"10.1088/1361-6498/ad4b26","DOIUrl":"10.1088/1361-6498/ad4b26","url":null,"abstract":"<p><p>Following the accident at the Fukushima Daiichi Nuclear Power Station, evacuation orders were issued for the surrounding communities. In order to lift the evacuation order, it is necessary to determine individual external doses in the evacuated areas. The purpose of this study was to determine the quantitative relationship between individual external doses and ambient dose rates per hour as conversion coefficients. More specifically, individual external doses of Tokyo Electric Power Company Holdings employees in difficult-to-return zone were measured broadly over a long period (fiscal year 2020 to fiscal year 2022). To obtain highly accurate estimates, we used not only ambient dose rates based on airborne radiological monitoring data, but also Integrated dose rate map data that had been statistically corrected to correspond to local ambient dose rate gradients on the ground. As a result, the conversion coefficients based on the ambient dose rate map measured by airborne radiological monitoring were 0.42 for the Evacuation-Order Lifted Zones (ELZs), 0.37 for the Special Zones for Reconstruction and Rehabilitation (SZRRs), and 0.47 for the Difficult-to-Return Zones without SZRRs (DRZs). On the other hand, the conversion coefficients based on the Integrated dose rate map which is a highly accurate dose rate map based on statistical analysis of various types of monitoring that have been studied in government projects in recent years, were 0.78 for the ELZs, 0.72 for the SZRRs and 0.82 for the DRZs. Using these conversion coefficients, the individual external dose can be estimated from two representative ambient dose rate maps provided by the government.</p>","PeriodicalId":50068,"journal":{"name":"Journal of Radiological Protection","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140923312","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}