The Accident Causation Model (or "Swiss Cheese Model") is a theoretical model that illustrates how accidents occur in organisations. The model focuses on both organisational hierarchy and human error. It postulates that the typical accident occurs because several (human) errors have occurred at all levels in the organisational hierarchy in a way that made such accident inavoidable. For example, decision makers may have made ill decisions when purchasing aircraft (fallible decisions), line management may have pushed for faster turnarounds (line management deficiencies), pilots may have felt pressurised to cope with a stressful climate, an unsafe culture and little rest (preconditions), the particular pilot who suffered the accident may have gotten distracted with other tasks three seconds prior to the accident (unsafe act), and the aircraft systems fail in providing unmistakable warnings of the danger (inadequate defences).
|Above example illustrates key concepts in the Accident Causation Model:
The Accident Causation Model was first published by Reason in 19901. Since then, it has progressively influenced contemporary views on the management of human error in organisations. For instance, the International Civil Aviation Organisation (ICAO) has formally adopted Reason's model to facilitate a systemic understanding of human factors issues within the aviation community (Wiegmann & Shappell, 20032).
Want to know more?
- AviationKnowledge - Human Factors Analysis and Classification System (HFACS)
- This AviationKnoweldge page discusses the HFACS model further.
- Wiki of Science - Accident Causation Model
- This webpage provides additional information on Reason's Accident Causation Model including a discussion of key concepts and criticisms to the model.