Radiation protection dosimetry最新文献

The objective of this work was to evaluate the radiation exposure received by workers in the nuclear medicine department of a private hospital in Bogotá, Colombia, during the period 2022-2023. The Hp (10) and Hp (0.07) readings for 15 workers including nuclear medicine (NM) physicians, nurses, and technologists who performed tasks in PET/CT and SPECT/CT were retrieved and analysed retrospectively. The results showed that in 2022, the average accumulated Hp (10) values for NM physicians, nurses, and technologists were, 1.5 ± 0.3 mSv, 1.9 ± 0.4 mSv, and 2.1 ± 0.6 mSv, respectively. Compared with 2022 (9.45 mSv vs 16.07 mSv), the mean annual extremity doses to nurses and technologists increased by 37.5% and 44.6%, respectively, in 2023 (15.11 mSv vs 29.05 mSv), due to the increase in the number of procedures. Technologists, particularly those responsible for preparing and administering the radiopharmaceuticals in PET/CT, recorded the maximum annual effective dose (3.0 mSv) and extremity dose (91.3 mSv) during 2022 and 2023.

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 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 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 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 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 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.

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 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.

This study investigates and analyzes the abnormal results of personal dose monitoring among radiation workers in Chongqing from 2021 to 2024, aiming to provide a scientific basis for occupational health management and radiation protection practices. The Registration Form for Investigation of Occupational External Exposure Individual Monitoring Doses was issued to individuals whose single monitoring results exceeded the investigation level. Detailed investigations were conducted to identify the causes of abnormal doses, including on-site radiation protection testing when necessary. From 2021 to 2024, a total of 1043 abnormal personal doses were recorded among 182 014 monitoring instances, yielding an abnormal rate of 0.57%. Diagnostic radiology and interventional radiology workers accounted for the majority of cases, at 64.43% and 22.53%, respectively. Most abnormal doses were below 5 mSv (72.48%). The primary causes included improper dosemeter usage (75.74%), increased workload (14.29%), and unidentified reasons (9.97%). The actual exposure rate was significantly higher among interventional radiology workers (47.66%) and those in tertiary hospitals (28.67%). Strengthening radiation protection training, improving dosemeter usage compliance, and optimizing workload management are essential to reduce abnormal doses. Special attention should be given to interventional radiology workers and tertiary hospital staff to mitigate occupational radiation risks.