Episode Summary

Welcome back to part two of our three-part series on Safety I and Safety II by Erik Hollnagel. Today, we continue digging into the full story behind this book, its theories, and the conclusions drawn therein.

Episode Notes

Picking up where we left off, we begin our discussion with chapter three. Over the course of this episode, we talk about Hollnagel’s definition of Safety I, the myths of safety, and causality (among other things). Tune in for part two of our in-depth look at this important book.


Chapter 3.

  • Habituation.
  • Preoccupation with failure.
  • Work as imagined vs. work as actually performed.
  • A definition of Safety I.

Chapter 4.

  • The four myths of Safety I.
  • Causality.
  • Misinterpreting Heinrich.
  • Human error.

Chapter 5.

  • Deconstruction.
  • Linear and non-linear systems.
  • Cause and effect.
  • General takeaways from chapters 3-5.


“…I think this one particular idea of work as imagined/work as done has been thought about a lot in the time since this book was published…”

“What is this measure of successful work? What is this way that we would categorize something as successful, if it’s not, not having accidents?”

“It’s a misinterpretation of Heinrich to apply the ratios.”

“And that sort of criticism of the old to explain the new, I think is never as firm a foundation as clearly explaining what you’re sort of underlying ideas and principles are and then building on top of them.”


Safety I and Safety II: The Past and Future of Safety Management