This book contains comprehensive information and methodologies for preparing process equipment for maintenance and, ultimately, return to service. Specifically, this book addresses two phases of equipment handovers, providing information and tools to help personnel at manufacturing sites reduce their risks. The first phase is isolating and preparing equipment for maintenance. The second phase is returning the equipment back to service, applying specified operational readiness plans in addition to a traditional pre-startup safety review (PSSR).
Topics include understanding the unique types of hazards personnel might be exposed to, planning for and executing decontamination and de-energization plans, and safely recommissioning the equipment for its return to service. Case studies, examples, and incident investigation discussions provide the reader with invaluable practical learnings that, when applied, help reduce the likelihood of another similar operational incident from occurring at their facility.
Table of Contents
List of Figures xii
List of Tables xiii
List of Case Studies xiv
Acronyms and Abbreviations xvi
Glossary xix
Acknowledgments xxvii
Dedication xxix
Foreword xxxi
Preface xxxii
1 Introduction 1
1.1 Purpose and Scope of the Book 1
1.2 Key Definitions Relevant to Preparing Equipment for Maintenance and Return to Service 3
1.3 Overview of the Main Focus Areas 3
2 Regulation and Process Safety 5
2.1 Regulatory Aspects 5
2.2 Company Standards and Safe Systems of Work 6
2.3 Process Safety and Personal Safety 8
3 Understanding the Hazards 11
3.1 Information Requirements-Process Safety Information 11
3.2 Equipment Hazards 12
3.3 Energy Hazards 17
3.4 Simultaneous Operations 24
3.5 Human Factors 24
3.6 Frequently Encountered Issues when Preparing Equipment for Isolation 25
3.7 Summary 26
4 Planning for Isolation and Decontamination 27
4.1 Plan Considerations 27
4.2 Risk Assessment 29
4.3 Isolation/Decontamination - Which Comes First? 35
4.4 Planning The Energy Isolation 36
4.5 Planning for Decontamination and Decommissioning 39
4.6 Disposal of Chemicals from Decontaminated Processes 43
4.7 Planning for Return to Service 43
4.8 Changing Plans 46
5 the Decontamination Plan 47
5.1 Documented Plan 47
5.2 Phase of Decontamination 49
5.3 Managing the Decontamination Hazards and Risks 50
5.4 Training for Decontamination 53
5.5 Difficult Decontaminations 55
5.6 Moving Decontaminated Equipment 57
5.7 Checklists and Equipment Identification 57
6 Executing the Decontamination Plan 59
6.1 Sharing the Plan 59
6.2 Tracking the Plan 60
6.3 Completing and Documenting Execution of the Plan 63
6.4 Complex Decontamination Plans 64
6.5 Equipment Readiness for Energy Isolation 66
6.6 Summary 66
7 Isolation and Decontamination Plan Examples 69
7.1 Isolating/Decontaminating Lines with Toxic Materials using “Double Block and Bleed” 69
7.2 Isolation/Decontamination for Vessel Entry 73
7.3 Isolation for Longer Term/Mothballing 77
7.4 Isolating/Decontaminating Butyl Lithium Storage Systems 78
7.5 Example - Isolating/Decontaminating a Toluene Diisocyanate Reactor Train 85
7.6 Summary 92
8 Overview of Energy Isolation 93
8.1 Degrees of Isolation 93
8.2 Human Factors in Energy Isolation 95
8.3 Designing for Energy Isolation 96
8.4 Locking and Labelling 98
8.5 Documenting Energy Isolation 99
8.6 Chemical Process Isolation 101
8.7 Electrical Isolation 101
8.8 Mechanical, Potential and Natural Energy Sources 103
8.9 Nuclear Radiation 103
8.10 Summary 104
9 Written Energy Isolation Plans (eip) 105
9.1 De-isolation, Testing, and Restart Considerations 106
9.2 Risk Level 106
9.3 Documentation - Safe Work Permit and EIP 109
9.4 Piping and Instrument Diagram (P&ID) Symbols for Process Isolation 110
9.5 Forms and Types of Energy Isolation 112
9.6 Lock - Tag - Try 114
9.7 Final Verification Before Release to Work 114
9.8 First Line Break 116
9.9 Monitoring Isolations 117
9.10 Summary 118
10 Specific Isolation Requirements 119
10.1 Process/Instrument Isolation 119
10.2 Electrical Isolation 120
10.3 Mechanical and Potential Energy and Natural Energy Isolation 122
10.4 Nuclear Radiation 123
10.5 Boundary Isolation 124
10.6 Specialized Isolation Techniques 124
10.7 Field Verification and Changes to Isolation 125
10.8 Summary 125
11 Reversing the Isolation Plan 127
11.1 Job Completion and Transfer of Equipment Ownership 127
11.2 De-isolation Procedure 127
11.3 Process De-isolation 130
11.4 Vents and Drains 132
11.5 De-isolation of Other Sources of Energy 132
11.6 Cleanliness 132
11.7 Bolts, Flanges, and Gaskets 133
11.8 Changes to Isolation Boundary 133
11.9 Summary 133
12 Recommissioning 135
12.1 Checks for Debris 137
12.2 Cleaning and Flushing 138
12.3 Purging 138
12.4 Leak/Pressure Testing 140
12.5 Functional Checks 144
12.6 Walk the Line (WTL) 146
12.7 Delayed Return to Service 147
13 Pre-startup Safety Review 149
13.1 PSSR and Returning Equipment to Service 149
13.2 PSSR Overview 152
13.3 PSSR Example: Short Form 152
13.4 Summary 156
14 Equipment Startup 157
14.1 Participation and Communication 157
14.2 Specific Startup Issues 158
14.3 Startup of Mothballed Equipment 161
15 Conclusion 165
Appendix A: Work Permit 167
Appendix B: Walk the Line 171
Appendix C: Decontamination Certificate 177
Appendix D: Long Form for Higher Risk/Complex Pssr 179
References 189
Index 197
