Risk Analysis

Foreword xiii PART 1. GENERAL CONCEPTS AND PRINCIPLES 1 Chapter 1. Introduction 3 1.1. What is risk management? 3 1.2. Nature of risks 4 1.3. Evolution of risk management 6 1.4. Aims of this book 12 Chapter 2. Basic Notions 13 2.1. Formalization of the notion of risk 13 2.2. Hazard and sources of hazard 16 2.3. Stakes and targets 17 2.4. Vulnerability and resilience 18 2.5. Undesirable events and scenarios 18 2.6. Accidents and incidents 20 2.7. Safety 20 2.8. Likelihood, probability and frequency 21 2.9. Severity and intensity 22 2.10. Criticality 23 2.11. Reducing risk: prevention, protection and barriers 23 2.12. Risk analysis and risk management 25 2.13. Inductive and deductive approaches 26 2.14. Known risks and emerging risks 27 2.15. Individual and societal risks 27 2.16. Acceptable risk 28 2.17. The ALARP and ALARA principles 29 2.18. Risk maps 31 Chapter 3. Principles of Risk Analysis Methods 33 3.1. Introduction 33 3.2. Categories of targets and damages 35 3.3. Classification of sources and undesirable events 36 3.4. Causes of technical origin 40 3.5. Causes linked to the natural or manmade environment 46 3.6. Human and organizational factors 46 Chapter 4. The Risk Management Process (ISO31000) 53 4.1. Presentation 53 4.2. ISO31000 standard 55 4.3. Implementation: the risk management process 61 PART 2. KNOWLEDGE REPRESENTATION 71 Chapter 5. Modeling Risk 73 5.1. Introduction 73 5.2. Degradation flow models 74 5.3. Causal modeling 77 5.4. Modeling dynamic aspects 87 5.5. Summary 90 Chapter 6. Measuring the Importance of a Risk 93 6.1. Introduction 93 6.2. Assessing likelihood 96 6.3. Assessment of severity 102 6.4. Risk assessment 109 6.5. Application to the case of occupational risks 113 6.6. Application to the case of industrial risks 118 Chapter 7. Modeling of Systems for Risk Analysis 123 7.1. Introduction 123 7.2. Systemic or process modeling 126 7.3. Functional modeling 128 7.4. Structural modeling 131 7.5. Structuro-functional modeling 134 7.6. Modeling the behavior of a system 137 7.7. Modeling human tasks 140 7.8. Choosing an approach 145 7.9. Relationship between the system model and the risk model 146 PART 3. RISK ANALYSIS METHODS 151 Chapter 8. Preliminary Hazard Analysis 153 8.1. Introduction 153 8.2. Implementation of the method 155 8.3. Model-driven PHA 165 8.4. Variations of PHA 166 8.5. Examples of application 169 8.6. Summary 175 Chapter 9. Failure Mode and Effects Analysis 179 9.1. Introduction 179 9.2. Key concepts 181 9.3. Implementation of the method 187 9.4. Model-based analysis 195 9.5. Limitations of the FMEA 197 9.6. Examples 198 Chapter 10. Deviation Analysis Using the HAZOP Method 201 10.1. Introduction 201 10.2. Implementation of the HAZOP method 201 10.3. Limits and connections with other methods 208 10.4. Model-based analysis 209 10.5. Application example 210 Chapter 11. The Systemic and Organized Risk Analysis Method 211 11.1. Introduction 211 11.2. Implementation of part A 214 11.3. Implementing part B. 224 11.4. Conclusion 228 Chapter 12. Fault Tree Analysis 229 12.1. Introduction 229 12.2. Method description 230 12.3. Useful notions 231 12.4. Implementation of the method 234 12.5. Qualitative and quantitative analysis 237 12.6. Connection with the reliability diagram 242 12.7. Model-based approach 243 12.8. Examples 244 12.9. Common cause failure analysis 247 Chapter 13. Event Tree and Bow-Tie Diagram Analysis 253 13.1. Event tree 253 13.2. Bow-tie diagram 259 Chapter 14. Human Reliability Analysis 263 14.1. Introduction 263 14.2. The stages of a probabilistic analysis of human reliability 267 14.3. Human error classification 269 14.4. Analysis and quantification of human errors 274 14.5. The SHERPA method 278 14.6. The HEART method 280 14.7. The THERP method 282 14.8. The CREAM method 288 14.9. Assessing these methods 291 Chapter 15. Barrier Analysis and Layer of Protection Analysis 293 15.1. Choice of barriers 293 15.2. Barrier classification 295 15.3. Barrier analysis based on energy flows 297 15.4. Barrier assessment 299 15.5. Safety instrumented systems 301 15.6. The LOPA method 307 PART 4. APPENDICES 319 Appendix 1. Occupational Hazard Checklists 321 Appendix 2. Causal Tree Analysis 327 Appendix 3. A Few Reminders on the Theory of Probability 329 Appendix 4. Useful Notions in Reliability Theory 335 Appendix 5. Data Sources for Reliability 341 Appendix 6. A Few Approaches for System Modelling 347 Appendix 7. Case Study: Chemical Process 355 Appendix 8. XRisk Software 361 Bibliography 363 Index 369