A review of the principles of the safety of softwarebasedequipment, this book begins by presenting the definition principlesof safety objectives. It then moves on to show how it is possibleto define a safety architecture (including redundancy,diversification, errordetection techniques) on the basis of safetyobjectives and how to identify objectives related to softwareprograms. From software objectives, the authors present thedifferent safety techniques (fault detection, redundancy andquality control). Certifiable system aspects aretaken into account throughout the book. Contents 1. Safety Management.2. From System to Software.3. Certifiable Systems.4. Risk and Safety Levels.5. Principles of Hardware Safety.6. Principles of Software Safety.7. Certification. About the Authors JeanLouis Boulanger is currently an Independent Safety Assessor(ISA) in the railway domain focusing on software elements. He is aspecialist in the software engineering domain (requirementengineering, semiformal and formal method, proof andmodelchecking). He also works as an expert for the French notifiedbody CERTIFER in the field of certification of safety criticalrailway applications based on software (ERTMS, SCADA, automaticsubway, etc.). His research interests include requirements,software verification and validation, traceability and RAMS with aspecial focus on SAFETY.