An Overview of System Safety Assessment

This chapter provides an introduction to the steps involved in creating dependable systems. This starts with a description of functional hazard assessment (FHA). The steps involved in preliminary system safety assessment (PSSA) and system safety assessment (SSA) are reviewed. The chapter introduces fault tree analysis (FTA) and failure modes and effects analysis (FMEA) as important tools in the safety assessment process. This chapter also introduces the basics of probability theory which can guide quantitative assessment. The concepts behind common cause analysis are introduced. To make the book self-contained, more detailed mathematical concepts are presented in the appendices which can be skipped by less mathematically inclined readers.