In this episode, we explore Professor James Reason's Swiss Cheese Model, which helps explain how incidents occur when multiple safety barriers fail at different levels within a system. We discuss how organizational, supervisory, and individual errors can combine to create accidents, and how the holes in these barriers move and shift over time. Using dynamic models, we highlight that safety is an emergent property of a system, where small errors accumulate and can lead to larger, more significant failures. We also examine the role of human error, risk management, and attention to detail in preventing accidents and emphasize the complexity of real-world systems, where multiple factors often lead to a critical mass of failure before an incident happens.

Original blog: https://www.thehumandiver.com/blog/when-the-holes-line-up

Links: Animated simple Swiss Cheese model: https://vimeo.com/326723142

Big Hole model: https://vimeo.com/326723122

Little Hole model: https://vimeo.com/326723109

Tags:  English, Gareth Lock, Human Factors, Incident Investigation