Structural upgrade in three adjacent 6 MV linac bunkers operating simultaneously to limit exposure to radiation in controlled and uncontrolled areas

The increasing in cancer incidence and advancements in teletherapy technology have necessitated shielding verification in linear accelerator bunkers, which may involve structural changes. This work proposes a hybrid methodology that combines analytical calculations and Monte Carlo simulation (TOPAS/Geant4 simulation toolkit) to determine, validate, and optimise shielding thicknesses in three adjacent bunkers where next-generation 6 MV linear accelerators will operate simultaneously. Findings indicate that the current secondary barriers in the hospital structure comply with international radiation exposure limits. However, the primary barriers require modifications to ensure radiological protection in both controlled and uncontrolled areas.