Tehran University of Medical Sciences Frontiers in Biomedical Technologies 2345-5837 13 1 2026 01 20 222 231 Ikbal Bouadel High Energy Physics Laboratory - Modeling and Simulation (HEPL-MS), Faculty of Sciences, Department of Physics, Mohammed V University, Rabat, Morocco Morad El Kafhali Physical Sciences and Engineering, Innovative Research and Applied Physics (IRAP), Faculty of Sciences, Moulay Ismail University, Meknes, Morocco Soukaina Mefrah Department of Radiology, Provincial Hospital, Ministry of Health and Social Protection, Casablanca, Morocco Marziyeh Tahmasbi Department of Radiology Technology, School of Allied Medical Sciences Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Rajaa Sebihi High Energy Physics Laboratory - Modeling and Simulation (HEPL-MS), Faculty of Sciences, Department of Physics, Mohammed V University, Rabat, Morocco 2024 11 04 2025 02 11 Objective: In Morocco, significant disparities exist in observing national radiation protection standards, particularly in conventional radiology for pediatric patients. This cross-sectional study aims to establish Moroccan diagnostic reference levels (DRLs) for pediatric thorax radiography. Methods: Thorax radiography examinations of  208 pediatric patients (newborns up to 18 years old) from four public hospitals in Morocco were evaluated. Patient demographics (age, gender, weight), and scan parameters were recorded to calculate radiation doses using CALDOSE_X 5.0 software, quantifying entrance surface air kerma (ESAK) in mGy. The study samples were divided into five age groups (age <1 month, 1 month ≤ age< 4 years, 4 years ≤ age< 10 years, 10 years ≤ age< 14 years, and 14 years ≤ age < 18 years). The third quartile (P75) of calculated ESAK in mGy and kinetic energy released per unit mass (KERMA)-area product (KAP), in mGy.cm² for each group were analyzed. Statistical analysis was performed using SPSS version 21. Results: The P75 values for ESAK (mGy) and KAP (mGy.cm²) diagnostic reference levels across age groups were: 0.61, 0.69, 0.68, 0.82, and 1.29 for ESAK, and 350.25, 566.07, 499.14, 950.62, and 1816.06 for KAP. The calculated regional DRLs for pediatric thorax radiography exceeded the published values for thorax protocols in some European countries. The irradiated surfaces significantly impacted the received doses of patients up to 10 years old (p-values of 0.004, 0.000, and 0.001). Conclusions: Adapting the irradiation surface to patient morphology is crucial, requiring precise control over exposure factors, radiation field size, and protocol selection. https://fbt.tums.ac.ir/index.php/fbt/article/view/1140 https://fbt.tums.ac.ir/index.php/fbt/article/download/1140/517