Normal Accident Theory and Swiss Cheese Model
1. Executive Summary
Normal accident theory and Swiss cheese model are influential models in studying system accident causation. This paper is going to help us to gain understanding of both models and to critically compare them. The first part of the study is an introduction of the both models. In the second part, Three Mile Island nuclear accident will be taken as an example to see how the models analyse causations of an accident. In this part, the fact of the accident will be presented first, then normal accident theory and Swiss cheese model will be invited to identify the causes of the accident respectively. The evaluation and comparison of the two models will be discussed in the final part. Both models conclude that accidents are unavoidable, while Swiss cheese model provides general methods to reduce accidents. Normal accident theory views technology itself as the main factor that contributes to accidents, however, Swiss cheese model has the opinion that accidents resulted from interaction of multiple factors from different levels in organization.
2. Introduction and Aims
System accident is regarded as unpredictable and inevitable in high-risk system because of the system’s complexity. Both normal accident theory and Swiss cheese model are accident theories to study accident causation. The study aims to understand how both accident models work and compare the two models to see what contributions and limitations of each of them. Three Mile Island accident is one of the most significant nuclear accidents in history. It is a typical accident in complex and high-hazard system. There have been plenty of studies to analyse the accident. Therefore, Three Mile Island accident will be a helpful case for us to study the models.
3. Accident Models Study
3.1 Introduction of Accident Models
Normal Accident Theory
Charles Perrow termed the system accidents as “normal accident”. He described systems by two important dimensions, interaction and coupling. Interaction
Normal accident theory and Swiss cheese model are influential models in studying system accident causation. This paper is going to help us to gain understanding of both models and to critically compare them. The first part of the study is an introduction of the both models. In the second part, Three Mile Island nuclear accident will be taken as an example to see how the models analyse causations of an accident. In this part, the fact of the accident will be presented first, then normal accident theory and Swiss cheese model will be invited to identify the causes of the accident respectively. The evaluation and comparison of the two models will be discussed in the final part. Both models conclude that accidents are unavoidable, while Swiss cheese model provides general methods to reduce accidents. Normal accident theory views technology itself as the main factor that contributes to accidents, however, Swiss cheese model has the opinion that accidents resulted from interaction of multiple factors from different levels in organization.
2. Introduction and Aims
System accident is regarded as unpredictable and inevitable in high-risk system because of the system’s complexity. Both normal accident theory and Swiss cheese model are accident theories to study accident causation. The study aims to understand how both accident models work and compare the two models to see what contributions and limitations of each of them. Three Mile Island accident is one of the most significant nuclear accidents in history. It is a typical accident in complex and high-hazard system. There have been plenty of studies to analyse the accident. Therefore, Three Mile Island accident will be a helpful case for us to study the models.
3. Accident Models Study
3.1 Introduction of Accident Models
Normal Accident Theory
Charles Perrow termed the system accidents as “normal accident”. He described systems by two important dimensions, interaction and coupling. Interaction