The application of virtual reality (VR) in fire safety training has grown significantly in recent years. This study explores the integration of VR technology for fire safety education within an internal department of a teaching hospital in Taiwan, structured in four stages: 1. Establishment of potential hazard map and spatial inventory: Experts conducted on-site inspections to identify high-risk areas and propose countermeasures. Spatial dimensions and equipment placements were documented to create a hazard map highlighting fire risks. 2. 3D modelling and Fire Dynamics Simulator (FDS) simulation: Separate 3D models were created for Fire Dynamics Simulator (FDS) and Unreal Engine due to differing format requirements. AutoCAD was utilized for Fire Dynamics Simulator (FDS) modeling, incorporating partition walls and ventilation systems, while Blender was employed for VR modeling. Fire Dynamics Simulator (FDS) simulations visualized smoke flow and thermal data, which were converted into a.xls file and integrated into VR to enable real-time user exposure calculations, supporting gamified training. 3. Experience design: The team developed training flows, tasks, and evaluation criteria using hazard maps. Storyboards guided VR content creation, while UI elements such as icons and layouts improved user interaction. 4. System development and optimization: A prototype was developed and refined through usability testing. Post-test scores improved from 53.1 to 64.7, moving usability from “not recommended” to “not actively recommended,” with further refinements planned. Although current usability remains below the recommended level, this study confirms the feasibility and potential of integrating Fire Dynamics Simulator (FDS) data into 3D VR-based fire safety training. Improvements will be pursued in the future to achieve fully recommended usability standards.