Practical Hazops, Trips and Alarms

Contents......Page 7
Preface......Page 10
1.2 Introduction to hazards and risk management......Page 15
1.3 Risk assessment......Page 24
1.4 Concepts of Alarp and tolerable risk......Page 29
1.5 Regulatory frameworks and examples from EU and USA......Page 35
1.6 Methods of identifying hazards......Page 40
2.1 Introduction......Page 45
2.2 Methodologies for hazard study 1......Page 51
2.3 Process hazard study 2......Page 54
2.4 Practical example of hazard 2 application......Page 67
2.6 Conclusion on hazard studies 1 and 2......Page 78
3.1 Risk reduction measures......Page 79
3.2 Terminologies and standards for safety systems......Page 80
3.3 Equipment under control......Page 81
3.4 Protection layers......Page 86
3.5 The role of alarms in safety......Page 92
3.6 Alarm types and do they qualify as safeguards?......Page 95
3.7 Identification and design of safety-related alarms......Page 96
3.8 Key design principles for alarms......Page 101
3.9 SIS, principles of separation......Page 104
3.10 Simple and complex shutdown sequences, examples......Page 106
3.11 Conclusions: the role of Hazops in defining alarms and trips......Page 109
4.1 Introduction......Page 111
4.2 Introduction to Hazop......Page 112
4.3 Overview of Hazop method......Page 113
4.4 Points to note on the examination procedure......Page 130
4.6 Hazop for batch processes and sequential operations......Page 134
4.7 Hazops for other disciplines......Page 138
4.8 Conclusions......Page 143
5.2 Organizing the Hazop......Page 144
5.3 The team leader and the team......Page 146
5.4 Practical exercise: hybrid batch process example......Page 155
6.1 Introduction......Page 157
6.2 Risk reduction by instrumented protection......Page 158
6.3 What affects the safety integrity of an instrument trip?......Page 163
6.4 Overview of IEC 61508......Page 164
6.5 Determining the safety integrity......Page 170
6.6 Design essentials to meet SIL targets......Page 173
6.7 Specifying the SIS requirements......Page 182
6.8 Documenting the SRS......Page 188
6.9 Conclusions......Page 193
7.1 Introduction......Page 194
7.2 Outline of methods......Page 195
7.3 Fault tree analysis......Page 199
7.5 Conclusions......Page 206
8.1 Introduction and objectives......Page 207
8.2 Equipment selection......Page 211
8.3 Key points about sensors and actuators......Page 220
8.4 Guidelines for the application of field devices in the SIS......Page 223
8.6 Technology issues......Page 230
8.7 Guidelines for final elements......Page 232
8.9 Summary of SIL vs cost......Page 238
9.2 Process description......Page 240
9.3 Safety requirements specifications......Page 245
9.4 Conclusion......Page 250
Appendix A: References used in the manual......Page 251
Appendix B: Some websites for safety systems information......Page 253
Appendix C: Notes on national regulations relevant to hazard study and safety management......Page 256
Appendix D: Software tools for hazard studies......Page 261
Appendix E: EPA case study of phenol resin hazards......Page 262
Appendix F: Expanded guideword table for continuous processes......Page 263
Appendix G: Methods of reporting......Page 265
Appendix H: Design and calibration of a risk graph......Page 267
Appendix I: Data capture sheet......Page 271
Appendix J: Glossary of terms used in hazard studies and safety-related systems......Page 273
Exercise 1......Page 278
Exercise 2......Page 280
Exercise 3......Page 282
Exercise 4......Page 289
Exercise 5......Page 294
Exercise 6......Page 300
Exercise 7......Page 302
Exercise 8......Page 308
Exercise 9......Page 316
Exercise 1......Page 320
Exercise 2......Page 322
Exercise 3......Page 323
Exercise 4......Page 328
Exercise 5......Page 334
Exercise 6......Page 337
C......Page 339
F......Page 340
H......Page 341
R......Page 343
S......Page 344
T......Page 345