The Application of Systems-Theoretic Accident Model and Process in the Systematic Nonlinear Analysis of Accidents in Car Industry

Background & objectives: Hundreds of methods have been introduced to analyze various events. Hence one of the effective and principle steps in accident analysis is proper and targeted selection of accident analysis method. Traditional methods of accident analysis in complex industries are not comprehensive and examine each components of the system separately. So, the use of new systematic methods to overcome these problems may be beneficial. The aim of present study was systematic analyzing of one deadly occupational accident in a car industry. Methods: This qualitative case study of analysis of an accident leading to the death in a car industry was performed using systems-theoretic accident model and process (STAMP) in 2018. For this study, the documentation of work accidents archived from 2008 to 2012 was reviewed. Then, a description of each specific accident and constraint, hierarchical levels of control and inadequate control measures were determined, and ultimately the safety of the system was assessed in relation to each incident. Results: In analysis of the accident in assembly line, several factors were involved and interactions between various components of the socio-technical systems were effective in the incident, among which the insufficient measures of safety unit had the higher contribution.  Conclusion: The STAMP technique, by determining a control structure, as a systematic approach for analyzing this incident, has included several factors in the incident and, unlike the traditional methods, has not consider the incident as a component of the system. Therefore, it can be used as a useful tool for accident analysis, especially in complex and sensitive systems.