X-ray devices have become the most numerous radiation sources in China, with about 355 000 in service at the end of 2025, roughly twice the number of sealed radioactive sources. However, unlike the activity-based categorization used for sealed sources, X-ray devices still lack a quantitative classification framework. In China, they are assigned mainly by intended use, which can create inconsistencies between devices with different technical parameters and between licensed and exempted equipment. Using a random sample of about 50 000 registration records and 145 exempted X-ray device entries, this study proposes a parameter-based approach for administrative classification. The screening index combines tube voltage squared, effective tube current and a banded weekly beam-on-time factor. Applied at category level, it gives the same administrative class as the current system for 13 of 18 X-ray device categories, while identifying several categories that may warrant reconsideration. Applied to exempted devices, it also provides a more consistent boundary between exemption and Class III than tube voltage alone. Although intended for administrative screening rather than dosimetry or detailed risk assessment, the approach could support revision of X-ray device classification in China and provide a reference for other graded regulatory systems.
Computed tomography (CT) contributes substantially to medical radiation exposure, making routine dose monitoring and optimization necessary. This study assessed radiation dose indices for adult head, chest, and abdominal CT examinations at Ekiti State University Teaching Hospital, Ado-Ekiti, Nigeria, and derived preliminary local diagnostic reference levels (LDRLs). A retrospective review covered 60 examinations, with 20 examinations in each anatomical group. Volume CT dose index (CTDIvol) and dose-length product (DLP) were obtained from the scanner console, and the 75th percentile values were used to derive the LDRLs. Effective dose was estimated from DLP using region-specific conversion coefficients. Mean CTDIvol values were 40.06 ± 18.42 mGy for head, 18.90 ± 8.15 mGy for chest, and 17.29 ± 6.32 mGy for abdomen. Mean DLP values were 960.56 ± 220.8, 662.36 ± 296.4, and 714.47 ± 196.2 mGy·cm, respectively. Estimated mean effective doses were 2.02, 9.27, and 10.72 mSv. Head CT was within the European reference values used for comparison. Chest CT exceeded the reference values for CTDIvol and DLP, while abdominal CT exceeded the DLP reference value. The derived LDRLs provide an institutional baseline for dose review and protocol optimization.
This preliminary study evaluates beta and gamma radiation levels and related health risks in two Algerian thermal spas, H1 and H2. We focused on doses received by workers and visitors, especially near thermal pools and confined treatment rooms. Dose rates were measured using a LUDLUM 2403 radiometer with a Geiger–Müller detector under different conditions: ventilated vs unventilated rooms and empty vs water-filled pools. Absorbed dose rates ranged from 1.2×10⁻4 to 3.18×10⁻4 mSv/h for H1 and from 1.7×10⁻4 to 3.55×10⁻4 mSv/h for H2, higher in humid, unventilated areas. Annual effective doses for workers varied between 0.15–0.27 mSv/y in H1 and 0.19–0.40 mSv/y in H2, while visitor doses remained very low (≤ 0.01 mSv/y). Excess lifetime cancer risk (ELCR), the annual inhalation equivalent dose to the lung (EInh), and estimated lung cancer per million people per year (LCC) cases were all well below internationally recommended reference levels showing negligible long-term risk. Benchmarking against international studies shows that our measured values are consistent with reported data. These results highlight the importance of ventilation to limit radon accumulation and provide a baseline for further studies in Algerian thermal facilities.
Background : Cone beam computed tomography (CBCT) is widely used in image-guided radiotherapy (IGRT) to improve the accuracy of treatment, particularly in the thoracic and pelvic regions. However, repeated CBCT acquisitions raise concerns regarding cumulative radiation exposure, particularly to radiosensitive organs. Purpose : This study aims to provide a comprehensive dosimetric analysis of CBCT imaging protocols, focusing on size-specific dose estimates (SSDE) as a patient-centred metric that incorporates anatomical dimensions, such as anterior–posterior (AP) and lateral (LAT) diameters, to more accurately reflect absorbed doses. Methods : CBCT data were collected retrospectively from clinical procedures using standard thoracic and pelvic protocols. Manual calculations of SSDE were performed and compared across patients with different anatomical sizes. Dose variability was analysed in relation to patient dimensions. Results : Significant inter-patient variability was observed in SSDE values, ranging from 45.2 mGy to 271.46 mGy for thoracic imaging and from 229.31 mGy to 909.11 mGy for pelvic imaging. These corresponded to approximately 0.09–0.44% and 0.76–1.16% of the total prescribed therapeutic dose, respectively. Notably, smaller patients received disproportionately higher SSDE values, primarily due to reduced tissue volume and increased radiation concentration. Conclusion : The findings highlight the limitations of using fixed-dose metrics such as CTDIvol and emphasise the importance of incorporating SSDE into routine clinical practice. Personalised imaging protocols based on patient size are recommended to reduce unnecessary radiation exposure, particularly for paediatric and small-sized patients, while maintaining adequate image quality.
This cross-sectional observational study aimed to identify factors influencing radiation personal protective equipment (RAD-PPE) adherence among nurses in interventional radiology (IR) departments in Saudi Arabia, using the Health Belief Model (HBM). A total of 230 IR nurses were recruited via convenience sampling from multiple hospitals between August 2024 to February 2025. Data were collected using a structured questionnaire assessing demographic characteristics, adherence status, and HBM constructs. The Mann-Whitney U test and multivariate logistic regression were used for analysis. Results showed that 59% of nurses were fully committed to RAD-PPE use. Fully committed nurses reported higher perceived susceptibility, severity, benefits, cues to action, and self-efficacy, and fewer perceived barriers. In the multivariate model, perceived benefits (AOR = 1.50, p = 0.005), cues to action (AOR = 1.80, p = 0.020), self-efficacy (AOR = 2.00, p = 0.012), and perceived barriers (AOR = 0.40, p = 0.018) were independent predictors of adherence, alongside education level and hospital type. Risk awareness alone did not predict adherence when practical and motivational factors were accounted for. Confidence in correct use, perceived benefits, and institutional prompts were the strongest drivers of full adherence.
