A γ-ray calibration field using a sealed 133Ba source for photon energy in the 300-400 keV range was established at the Japan Atomic Energy Agency to evaluate radiation protection devices under low dose rate conditions....A γ-ray calibration field using a sealed 133Ba source for photon energy in the 300-400 keV range was established at the Japan Atomic Energy Agency to evaluate radiation protection devices under low dose rate conditions. To suppress low-energy γ-ray components, a 2-mm lead filter was applied. The photon fluence spectrum was measured using a CdTe spectrometer and an unfolding method, yielding a spectrum with a mean energy of 321 keV. Reference air kerma rates were determined using ionization chambers calibrated in a 137Cs field, with energy correction factors applied. Spectrometry using a CeBr₃ scintillation spectrometer combined with the G(E) function method was employed to validate these corrections. Spectrum-averaged conversion coefficients were derived from the measured spectrum, indicating equivalence to the N-400 radiation quality. This field provided air kerma rates from 0.22 to 2.13 μGy h-1, suitable for testing devices used in environmental monitoring and nuclear emergency response.
The aim of this study was to assess the impact of a state-of-the-art 32 cm axial field-of-view GE Omni Legend PET/CT system on administered activity and image quality, and to update Diagnostic Reference Levels (DRLs). Sy...The aim of this study was to assess the impact of a state-of-the-art 32 cm axial field-of-view GE Omni Legend PET/CT system on administered activity and image quality, and to update Diagnostic Reference Levels (DRLs). System performance was evaluated using NEMA NU 2-2018 measurements and EARL2 accreditation tests. A comparison with the previous 5-ring GE Discovery IQ scanner was performed to analyze the administered activity, scan duration and image quality with and without Artificial Intelligence driven reconstruction. A retrospective analysis of standard-sized adult examinations was conducted to derive updated DRLs values. Omni Legend demonstrated improved sensitivity and Noise Equivalent Count Rate, enabling up to 60% reduction in injected activity while maintaining or improving image quality. Deep learning reconstruction enhanced image quality, particularly at lower administered activities. The DRLs were lower than the national and international reference levels, supporting dose optimization in clinical practice.
Monitoring radiation doses is critical for safety in nuclear medicine (NM) departments. This study assessed personal and ambient radiation doses during routine NM procedures and compliance with International Commission o...Monitoring radiation doses is critical for safety in nuclear medicine (NM) departments. This study assessed personal and ambient radiation doses during routine NM procedures and compliance with International Commission on Radiological Protection (ICRP) limits at the new NM department of Abu Ali Sina Hospital, Shiraz, Iran. Between March and April 2024, 500 procedures involving 99mTc and 131I were performed. Personal dose equivalents Hp(10), Hp(3), and Hp(0.07) were measured for staff using calibrated TLD-100 dosemeters. Ambient doses were monitored across the department. Measured doses included 11.19 mSv (fingers), 14.62 mSv (hands), 0.11 mSv (whole body), and 0.03 mSv (eye lens), with Technologist 2 showing the highest hand dose. Ambient monitoring showed the highest dose rate (1.19 μSv/h) in the waiting area near the hot lab, mainly from post-injection patients. While all doses remained within ICRP limits, the findings indicate the need for improved shielding and optimized workflow to minimize extremity and environmental exposure.
In recent years, more and more electronics have been exposed to the mixed radiation field. The radiation resistance of electronics has been paid more and more attention to and the China Spallation Neutron Source (CSNS) l...In recent years, more and more electronics have been exposed to the mixed radiation field. The radiation resistance of electronics has been paid more and more attention to and the China Spallation Neutron Source (CSNS) linac tunnel provides a natural mixed radiation field. One of the radiation hotspots induced by beam loss when the CSNS linac regularly operates is the debuncher component in the beamline. The radiation level around the debuncher was measured by dose monitors and simulated by the FLUKA code simultaneously. The results of measurement and simulation are consistent, which means that the model simulated by the FLUKA code is consistent with the actual situation. The energy spectrum of the mixed radiation field at CSNS was first simulated by the FLUKA code. The mixed radiation field is composed of charged and neutral hadrons (protons and neutrons), photons, and electrons over a range of energies. This radiation field is suitable for the radiation damage effect tests of electronic components operating in the mixed radiation environment, especially for the electronic components used in the accelerator tunnel.
Radiochromic films are a reliable tool for quantifying ultraviolet exposure dose. When used without modification, these films enable a simple, low-cost measurement of accumulated dose over time which is amenable to perso...Radiochromic films are a reliable tool for quantifying ultraviolet exposure dose. When used without modification, these films enable a simple, low-cost measurement of accumulated dose over time which is amenable to personal exposure monitoring. This study presents two methods to expand the utility of these films for dosimetry applications. One approach utilized an ultraviolet radiation attenuator to effectively extend the usable dose range of radiochromic films. The attenuators have the added advantage of obscuring the film from view so the color change of the film due to increasing exposure dose is not visible. The practical use of these films with attenuators over prolonged exposure periods is highlighted as a case study in this manuscript. A second modification is the addition of a structure to limit the dose received by the film to an 80° field of view. Limiting the field of view of the film dosemeter provides for an estimate of the dose received by the eyes, accounting for protection provided by the ocular cavity, and the use of a dosemeter with a restricted field of view is included in recommendations for commissioning of ultraviolet lighting installations. Radiochromic films, when used in conjunction with these tools, offer an effective solution for extended dose ranges and eye-specific ultraviolet dose measurement in indoor spaces utilizing germicidal ultraviolet technologies.
Stabilini A, Geser FA, Kasprzak M
… +1 more, Mayer S
Radiat Prot Dosimetry
· 2026 Apr · PMID 41524733
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Californium neutron sources are fairly common and appreciated in ionizing radiation metrology. Due to the concomitant presence of different neutron-emitting radionuclides, the isotopic composition of the source ought to...Californium neutron sources are fairly common and appreciated in ionizing radiation metrology. Due to the concomitant presence of different neutron-emitting radionuclides, the isotopic composition of the source ought to be known for an accurate estimation of neutrons emitted by the source in time. This becomes more important with the ageing of the source, because the 252Cf predominant contribution reduces in favour of other neutron-emitting radionuclides. This work illustrates a methodology to estimate the relative neutron emission of the most important nuclides. The advantage of the suggested approach lies in the use of a set of dose-rate measurements spanning several years, typically available at laboratories, since periodical checks of the field are performed. The method illustrated was applied to a californium source present at Paul Scherrer Institute calibration laboratory, yielding an estimation of the ratio of the neutrons emitted by 252Cf and 250Cf. Since for calibration laboratories any alteration of the neutron energy distribution emitted by the source could influence the response of detectors, available data on neutron spectra emitted by these nuclides have also been compared.
Radiat Prot Dosimetry
· 2026 Apr · PMID 41511197
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Full text
Clinical audits have been implemented in Finland to healthcare organizations over 20 years. We introduce the outcomes of fourth round external clinical audits on medical radiological procedures following the implementati...Clinical audits have been implemented in Finland to healthcare organizations over 20 years. We introduce the outcomes of fourth round external clinical audits on medical radiological procedures following the implementation of the EU Directive (Basic Safety Standards). We analyzed 31 external clinical audits on radiological practices in 2018-2022. The summarized strengths and recommendations from the audits were collected from the main auditing organization's database. 306 recommendations were given, 18% related to definitions of responsibilities, 16% to internal procedural guidelines, 16% to personnel education, and 25% to quality assurance and utilization of self-assessments of radiological procedures. Private and small organizations received less recommendations than large and public operators. Moreover, 215 strengths were reported, focusing on the clarity of responsibilities (21%) and excellence in quality assurance (15%). Reaching and maintaining feasible radiological diagnostic accuracy by consideration of radiation safety requires continuous quality assurance and development facilitated, and monitored by clinical audits.
Limited data exists on radiation exposure to trauma and orthopaedic (T&O) surgeons using modern imaging equipment and personal protective equipment (PPE) in theatre. This study investigated radiation doses to the chest a...Limited data exists on radiation exposure to trauma and orthopaedic (T&O) surgeons using modern imaging equipment and personal protective equipment (PPE) in theatre. This study investigated radiation doses to the chest and axilla during routine orthopaedic trauma practice by issuing 189 T&O surgeons with two thermoluminescent dosemeters each (worn on chest and axilla) for a continuous 3-month period. Surgeons also completed a survey on demographics, radiation safety training, PPE type and availability to assess links with radiation doses. No surgeon received a total dose resulting in them exceeding the 20 mSv/year dose limit set by the UK Health and Safety Executive's Ionizing Radiation Regulations 2017. Radiation exposure was not significantly linked to demographics or training. 58.8% of surgeons had not received formal radiation safety training within the past 3 years, and 90% were not routinely dose monitored. National guidance on radiation safety training and behaviours would reduce variability and ensure workplace safety.
This study aimed to design and characterize a compressible phantom that simulates adipose, glandular, and mixed breast tissues for mammography applications. Samples were prepared using paraffin gel wax, silicone oil, gla...This study aimed to design and characterize a compressible phantom that simulates adipose, glandular, and mixed breast tissues for mammography applications. Samples were prepared using paraffin gel wax, silicone oil, glass microspheres, and silicone. The linear attenuation coefficients and effective atomic numbers calculated at 15 keV were 0.986 cm-1 and 5.97 for adipose tissue, 1.381 cm-1 and 7.81 for glandular tissue, and 1.772 cm-1 and 6.91 for the mixed sample. Densities and Young's modulus values obtained from computed tomography and compression tests were 0.89 g·cm-3 and 24.75 kPa for adipose, 0.98 g·cm-3 and 31.26 kPa for glandular, and 0.95 g·cm-3 and 26.27 kPa for the mixed composition. Mammographic images were satisfactory, and the calculated mean glandular dose values closely matched those extracted from Digital Imaging and Communications in Medicine (DICOM) headers, with mixed and glandular samples showing similar values to patient data. Slight deviations from previously published results suggest potential areas for further refinement of phantom properties.
In 2020, Italy transposed Council Directive 2013/59/Euratom, establishing national criteria for identifying radon priority areas. In 2024, further guidance was provided by the adoption of the national radon action plan....In 2020, Italy transposed Council Directive 2013/59/Euratom, establishing national criteria for identifying radon priority areas. In 2024, further guidance was provided by the adoption of the national radon action plan. Between 2022 and 2025, priority areas were identified in a part of the country where adequate radon measurement surveys had been carried out. The main choices applied are outlined, and the current situation is presented for the first time, allowing parameters to be quantified, including the number of buildings involved and the expected number of buildings above the reference level within priority areas.
This study assesses natural radionuclide activity concentrations and their associated ingestion doses in thermal spring waters from Hammam Debagh (Guelma) and Hammam Salhin (Khenchela), northeastern Algeria. High-purity...This study assesses natural radionuclide activity concentrations and their associated ingestion doses in thermal spring waters from Hammam Debagh (Guelma) and Hammam Salhin (Khenchela), northeastern Algeria. High-purity germanium gamma-ray spectrometry was employed to quantify radionuclides from the 238U, 235U, and 232Th decay series, and 40K. All measured activities in Hammam Salhin were below detection limits. In Hammam Debagh showed detectable concentrations of 226Ra (4.53 ± 0.86 Bq l-1), 214Bi (4.89 ± 0.66 Bq l-1), 214Pb (4.27 ± 0.56 Bq l-1), and 212Pb (0.46 ± 0.26 Bq l-1), while 40K was below the minimum detectable activity. The estimated annual committed effective ingestion dose ranged from 58 to 926 μSv y-1 depending on water intake, with 226Ra contributing ~99 per cent of the total. Doses exceeded the WHO reference level of 0.1 mSv y-1 but remained below the International Commission on Radiological Protection (ICRP) dose limit of 1 mSv y-1. These results provide a preliminary radiological characterisation of Algerian thermal waters.
In this paper, neutron shields based on hydraulic lime-based brick samples were fabricated by adding various mass additive materials in proportions such as lime (CaCO3), titanium oxide (TiO2), hematite (Fe2O3), aluminum...In this paper, neutron shields based on hydraulic lime-based brick samples were fabricated by adding various mass additive materials in proportions such as lime (CaCO3), titanium oxide (TiO2), hematite (Fe2O3), aluminum oxide (Al2O3), calcium sulfate (CaSO4), silicon dioxide (SiO2), and boron carbide (B4C). Neutron attenuation factors such as neutron transmission factor, half-value layer, effective removal cross-section ΣR (cm-1), mean free path, and neutron flux were determined theoretically using Monte Carlo simulation GEANT4 and Fluka codes. Fast neutron absorption dose rate experiments were performed using a 241Am-Be source and a BF3 gaseous proportional detector. In addition, the absorbed dose values were theoretically determined using the Fluka code. All the obtained data were compared with the results of the examined reference samples (conventional concrete, some heavy concretes, and paraffin). All new brick materials were detected to have superior shielding capacities compared to the reference material. The proposed brick samples can be used as an alternative radiation protection material for regular shielding materials.
Radiation exposure risk to the lens of the eye varies based on where technologists assist during chest X-rays. In this study five radiologic technologists participated in the training for lens exposure reduction methods...Radiation exposure risk to the lens of the eye varies based on where technologists assist during chest X-rays. In this study five radiologic technologists participated in the training for lens exposure reduction methods proposed in previous studies, and the personal dose equivalent at a depth of 3 mm [Hp(3)] near the eyes were evaluated. Data were collected before and after the training. After the training, three radiologic technologists had 3%-27% decreases in Hp(3) at the measurement points, and the proportion of selecting the assistance position with the lowest Hp(3) increased. However, one technologist with extensive experience in chest X-ray examinations showed no significant differences in Hp(3) before and after the training. This suggests that the training is specifically effective for technologists with less experience in radiation-related work because the radiation protection education brought about behavioral changes in the radiologic technologists, leading to a reduction in their Hp(3).
Evaluation of radiological dose rate to aquatic non-human biota available at Kakrapar Atomic Power Station site, Gujarat, India has been carried out using Environmental Risks from Ionizing Contaminants: Assessment and Ma...Evaluation of radiological dose rate to aquatic non-human biota available at Kakrapar Atomic Power Station site, Gujarat, India has been carried out using Environmental Risks from Ionizing Contaminants: Assessment and Management tool. Radiological dose rate to five different varieties, each of fresh water weed and fish, were studied. Radiological dose rate (μGy.h-1) for aquatic weed and fish was found to be in the range of 5.2E-05 to 1.9E-03 and 1.1E-05 to 1.6E-03, respectively. Radiological dose rate for aquatic weed and fresh water fish available at Kakrapar Gujarat site was compared with worldwide reported values. The total dose rate for each organism is well within the screening dose rate criteria of 10 μGy.h-1. The Risk Quotients are calculated and found to be less than unity in all the cases. This indicates that the radiation exposure levels in the area are low and that the non-human biota at Kakrapar Gujarat site, India are not exposed to any statistically significant reactor released radionuclides.
This study compared radiation dose, vascular enhancement, and contrast-to-noise ratio (CNR) of 256-multidetector row computed tomography (MDCT) at 70 kVp with deep-learning reconstruction (DLR) to 64-MDCT at 80 kVp with...This study compared radiation dose, vascular enhancement, and contrast-to-noise ratio (CNR) of 256-multidetector row computed tomography (MDCT) at 70 kVp with deep-learning reconstruction (DLR) to 64-MDCT at 80 kVp with ASiR of cardiac CT angiography (CCTA) in infants with congenital heart disease. The contrast medium (CM) was 266 mg/kg for the 256-MDCT group and 600 mg/kg for the 64-MDCT group. In the 256- and 64-MDCT groups, the median values were 0.45 and 0.75 mGy for adjusted volume CT dose index (P < .05) and 4.98 and 8.00 mGy-cm for dose length product (P < .05). Despite a 49% CM reduction in the 256-MDCT group, vascular enhancement and CNR showed no significant differences (P > .05). The 256-MDCT at 70 kVp with DLR can maintain vascular CT enhancement and CNR while reducing CM by 49% and radiation dose by 41% in infant CCTA, compared with 64-MDCT at 80 kVp with ASiR.
This study investigates the contamination of sweet potatoes by 137Cs following a hypothetical radiological dispersion event, assessing its implications for food safety and public health. Given the increasing concerns abo...This study investigates the contamination of sweet potatoes by 137Cs following a hypothetical radiological dispersion event, assessing its implications for food safety and public health. Given the increasing concerns about nuclear energy expansion, this research is particularly relevant to agricultural systems, which are crucial to food security. Using HotSpot Health Physics Codes (v3.1.2), we simulated the radionuclide dispersion in a sweet potato farming area, considering environmental factors like atmospheric stability and soil properties. The model assesses the transfer of radioactive material to crops and the potential health risks to consumers. The evaluation links 137Cs exposure to an increased risk of leukemia, represented by the excess risk of its fatal occurrence over a lifetime, emphasizing the need for post-radiological incident monitoring. The results of the simulations suggest, for example, that the concentration of activity of 137Cs in the root of the sweet potato can vary by up to 3 orders of magnitude for the same location, depending on variations in the local atmospheric stability classes. Such sensitivity was also observed for the risk of developing radiation-induced leukemia, whose average values for the adopted radionuclide-to-plant Transfer Factors models may differ by up to 2 orders of magnitude depending on the same variables. Through computational modeling, this study offers insights into the threat posed by radiological contaminants in food chains and underscores the importance of surveillance measures in protecting public health.
The present study focuses on the measurements of specific activity levels of 14C in the atmospheric CO2 using the passive sampling technique coupled with benzene synthesis method. The purity of benzene, synthesized from...The present study focuses on the measurements of specific activity levels of 14C in the atmospheric CO2 using the passive sampling technique coupled with benzene synthesis method. The purity of benzene, synthesized from atmospheric CO2 was measured using the gas chromatography technique, and it was found that the purity of benzene was 99%. The Liquid scintillation counter was calibrated with a benzene sample synthesized from the NIST Oxalic acid standard, and the efficiency of the system is found to be 70.2% ± 0.8%. The passive sampling method was used to sample the atmospheric CO2. The atmospheric CO2 absorbed in 2N sodium hydroxide (NaOH) solution. The average amount of carbon absorbed in 2N NaOH solution is 5.27 ± 0.20 g for the sampling duration of 7 days. The measured specific activity 14C levels in the atmospheric CO2 varied from 240.9 to 250.0 Bq/kg C with an average specific activity of 246.3 ± 2.5 Bq/kg C.
This study evaluates the occupational equivalent doses to selected organs and tissues received by veterinary staff at the Veterinary Clinical Hospital of the University of Extremadura, where $\sim $7000 diagnostic imagin...This study evaluates the occupational equivalent doses to selected organs and tissues received by veterinary staff at the Veterinary Clinical Hospital of the University of Extremadura, where $\sim $7000 diagnostic imaging procedures (X-ray and computed tomography scans) are performed annually on patients of various sizes. Experiments were conducted with dosemeters positioned to simulate typical locations of veterinary operators during radiographic procedures under clinical conditions. Canine cadavers and equine anatomical specimens were used as animal patients, and scattered radiation exposure was measured at operator-relevant sites-including the hands, thorax, gonads, and eyes-both with and without protective equipment. The findings confirm that, with proper radioprotection measures, doses remain well below the legal limit (500, 50 and 20 mSv y$^{-1}$ for hands, eye lens and other tissues, respectively), even in worst-case scenarios-particularly during portable equine radiography exposure. However, it highlights the need for strict adherence to radiation safety protocols.
Children receive high radiation doses during interventional cardiology procedures and their sensitivity to radiation is higher than that of adults. A 4-year follow-up study was conducted in two large cardiovascular hospi...Children receive high radiation doses during interventional cardiology procedures and their sensitivity to radiation is higher than that of adults. A 4-year follow-up study was conducted in two large cardiovascular hospitals and a pediatric polyclinic with the objective of providing typical values. The median values of 454 cases obtained for fluoroscopy time, cumulative reference point air kerma (Ka,r) and air kerma-area product (PKA) by age range were 5.6 min, 53.6 mGy, and 4.1 Gy cm2 for <1 y; 4.3 min, 77.9 mGy, and 7.2 Gy cm2 for 1 to <5 y; 4.0 min, 41.4 mGy, and 7.4 Gy cm2 for 5 to <10 y; 4.4 min, 90.1 mGy, and 16.1 Gy cm2 for 10 to <16 y, respectively. The median values of 144 cases obtained for Ka,r and PKA by weight bands were 84.4 mGy and 7.4 Gy cm2 for <15 kg, 25.8 mGy and 3.7 Gy cm2 for 15-30 kg, 46.4 mGy and 9.2 Gy cm2 for 30-50 kg, and 154.0 mGy and 25.6 Gy·cm2 for >50 kg. Our results can serve as a dose comparison with local practice and as a basis for optimization between facilities.
This study examined the levels of gamma-emitting natural radionuclides in soils from 11 paddy fields across Taiwan's primary rice-producing regions and assessed the potential radiological risk to farmers. The mean activi...This study examined the levels of gamma-emitting natural radionuclides in soils from 11 paddy fields across Taiwan's primary rice-producing regions and assessed the potential radiological risk to farmers. The mean activities of 40K, 232Th, and 226Ra in the 66 soil samples were 591.0 ± 133.8, 45.4 ± 10.2, and 30.9 ± 6.6 Bq/kg, respectively, with variations among sites attributed to geological differences. The average activity ratios of 40K/226Ra (19.3) and 40K/232Th (13.1) were higher than global soil averages, suggesting a soil composition enriched in potassium-rich minerals, such as feldspar and mica. A strong positive correlation observed among 40K, 226Ra, and 232Th activities indicated a common geological origin. The radiological hazard was assessed by calculating the annual effective dose using the United Nations Scientific Committee on the Effects of Atomic Radiation (2010) methodology. The mean effective dose for farmers was estimated to be 46.5 ± 9.9 μSv/y, a value significantly below the public dose limit of 1000 μSv/y.