Underground mining fire hazards and the optimization of emergency evacuation strategies (EES): The issues, existing methodology and limitations, and way forward

Underground mine fires are associated with thermal and non-thermal hazards. Thermal hazards are primarily characterized by the release of heat into the underground confined space. The non-thermal hazards are noxious gases primarily carbon monoxide produced from incomplete combustion which may be circulated to other parts of the sub-surface environments through the ventilation network. Consequently, it is paramount to understand the interaction of possible fire scenarios and the underground ventilation system due to the hazards fire poses in such environments to design an appropriate emergency evacuation plan. This work aims to present a comprehensive review of the status of underground mine fire studies, techniques for emergency evacuation planning, the merits and limitations of the existing methods, the current best practices, and the way forward to develop an integrated smart solution for improved safety practices in underground environments. In addition, this study further identifies critical factors based on experimental and numerical fire studies that could substantially improve fire safety and emergency preparedness in underground confined environments, thus optimizing the management of emergency evacuation plans in such environments.