Yesterday’s bunkers, today’s technologies: how to expand the modulated workload without structural renovations?
DOI:
https://doi.org/10.29384/rbfm.2025.v19.19849001850Keywords:
Radioterapia, carga de trabalho, blindagem, medições radiométricas, otimização de recursosAbstract
The incorporation of modulated techniques in radiotherapy has raised new challenges for shielding adequacy in radiotherapy treatment bunkers, originally designed for conventional workloads. Renovating these structures is often impractical, and traditional reassessment methods, such as those from NCRP Report No. 151, show practical limitations for operating facilities. This study presents a practical analytical model based on direct dose rate measurements and an inverse calculation approach to quickly and safely estimate the maximum permissible workload, while complying with CNEN regulatory standards. We evaluated five Brazilian institutions, using real clinical profiles and bunker characteristics. The results showed that most facilities could increase the use of modulated techniques up to 100% without requiring structural modifications. Additionally, response surface modeling confirmed the mathematical consistency and operational reliability of the method. Compared to existing approaches, our model offers greater simplicity, faster application, and better alignment with actual construction features. This work provides a practical tool for expanding the use of advanced techniques and optimizing treatment capacity in radiotherapy centers, without compromising radiation protection, representing a strategic advancement for the management of oncology services.
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Copyright (c) 2025 Andre Gonçalves Prospero, Lucas Radicchi, Leandro Baptista, Beatriz Tomazzi, Herminiane Vasconcelos, Cristina Giolo, Flávio da Silva Guimarães, Thales Hilario Hungaro, Amanda Meletti, Fernanda Belletti, Taís Peron, José Carlos da Cruz
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