Abstract

Purpose: The purpose of this study is to analyze the fire risks associated with lithium-ion batteries in personal mobility devices (PMs) within urban railways and to propose emergency response strategies from a Business Continuity Planning (BCP) perspective to prevent and address these risks. In particular, the study aims to derive an effective safety management model by analyzing the critical impact that the physical vulnerability of underground spaces and thermal runaway phenomena have on the evacuation of vulnerable road users. Research Method: Scenarios were constructed based on existing railway accident databases and the Daegu subway fire case by setting variables such as fire scale, location of occurrence, and ventilation characteristics. Through this, the impact on the evacuation environment within underground spaces, such as the diffusion speed of toxic gases and reduced visibility during a lithium-ion battery fire, was quantitatively examined. Results: Analysis of the thermal runaway phase confirmed that heat transfer between battery cells begins approximately 2 to 5 minutes after the fire breaks out, leading to the rapid spread of toxic gases. In particular, the dense smoke generated by the fire drastically reduces visibility, revealing a survival threshold where voluntary evacuation by passengers becomes impossible. This suggests that an initial response system distinct from that for ordinary fires and the securing of special evacuation routes for the disabled are essential Conclusion: Given the unique characteristics of lithium-ion battery fires, it is urgent to introduce early off-gas detectors and expand specialized suppression equipment, such as Class D fire extinguishers and suffocation extinguishing blankets. Furthermore, to minimize casualties and maintain urban railway functions, an integrated safety management model must be established to secure a "30-minute golden time" for passenger safety in the subway environment by upgrading emergency response manuals for each accident stage and strengthening on-site response capabilities