← All chapters Chapter 02

Introduction

A fault tree should be derived from the system, not invented.

A structurally wrong tree yields wrong results with full mathematical rigor, so the structure must be derived from an ibd rather than guessed. Because the tree mirrors real fault propagation, its minimal cut sets are real combinations, not artifacts of how it was drawn. Fully addressed events, common causes, cascading failures, safety-measure placement, and reuse then fall out of the correct structure.