# The Full Lifecycle Evolution Model of Accidents: A Case Study of Underground Metal Mines in China
## 2 Methodology
### Full Lifecycle Evolution Model of Accidents
#### 2.2.1. Accident Evolution Process  
(1) Hazard Identification and Control  
Production accidents originate from various hazards present in the production environment, which are managed by personnel in accordance with the safety management system. From a preventive standpoint [19], effective control methods for identified hazards include elimination (M01), substitution (M02), engineering control (M03), monitoring (M04), and warning (M05). A failure in the management system refers to inadequate or ineffective management practices, policies, or procedures that result in accidents or incidents. Such failures can occur at different stages of the execution process, including the design, implementation, and maintenance of control measures [45]. This also involves supervision by safety management personnel at various levels, as well as the evaluation and improvement of control measures.  
(2) Accident Development Stages  
When supervisors discover through routine inspections that operators are not following established procedures, the parties responsible must take appropriate corrective actions. If these actions are inadequate, safety hazards may arise. If such hazards are not effectively addressed over time, and supervisory personnel fail to perform their oversight duties in subsequent inspections, the safety risks will continue to accumulate, eventually triggering the onset of a production accident.  
When hazardous energy is released due to insufficient control, the first step is to determine whether the energy is coupled with personnel. If no such coupling occurs, the event is classified as a near miss (or no-injury incident). If the energy does interact with personnel, the next consideration is whether the protective measures in place are effective. If these protective measures fail to mitigate the harmful energy, injury becomes inevitable, escalating the event into an actual accident. The severity of the accident's consequences will depend on the effectiveness of the on-site response and emergency rescue measures. The accident will conclude once the hazardous energy is either fully dissipated or brought back under control through appropriate actions.  
(3) Accident Consequence Analysis  
Currently, the analysis of accident consequences typically focuses on three areas: economic losses, personnel casualties, and social reputation. Accidents can result in significant direct and indirect economic losses, and even near-miss incidents can reduce productivity. Personnel casualties are a critical metric for evaluating accident severity and distinguishing near-misses from confirmed accidents. Social reputation is also impacted, as major accidents often damage an enterprise's public image, eroding public trust and market share. The analysis of accident outcome severity requires a comprehensive assessment of several factors, such as the magnitude of the hazardous energy, the number of individuals exposed at the time of release, and the effectiveness of emergency response measures. Different types of accidents may require distinct logical frameworks for determining their outcomes, and further specification is needed based on the specific accident scenario during practical application.