Episode Summary

Welcome back to another great episode of the Safety of Work podcast. Today, we dive into whether Swiss cheese is a helpful metaphor for understanding accident causation. We thought this would be a great topic to kick off the new year.

Episode Notes

The article we reference provides a historical account of the “Swiss Cheese Model”. Since there are many versions of this same diagram, we thought it best to look back through time and see the evolution of this particular safety model.


  • Why the model represents the presence of folklore in safety.
  • The methods used in Good and Bad Reasons.
  • The cognitive processes that lead to errors.
  • Whether the model represents accident causation appropriately.
  • A defense of the model.


“He’s just trying to understand this broad range of errors and sort of work with the assumption that there must be different cognitive processes.”

“It was initially, sort of, only published once in a medical journal as an oversimplification of his own diagram.”

“The other critique is that the model lacks guidance.”

“ ‘I never intended to produce a scientific model’ is the worst excuse possible that an academic can give in defense of their own model.”


Good and Bad Reasons: The Swiss Cheese Model and its Critics