1. Are You Ready for an SIS? What to do before starting on your SIS…and after it’s installed March 24, 2009

2. Presenter: Mike Schmidt, P.E.  Principal Bluefield Process Safety  Principal Safety Consultant Emerson Process Management Are You Ready for an SIS?, ©2009Slide 2

3. Before starting on an SIS  Steps of the Safety Life Cycle and Why They Matter  SIFs and SIL Assignment  The SRS  After the SIS is installed – a conversation Are You Ready for an SIS?, ©2009Slide 3

4. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Process Design 1 1 Are You Ready for an SIS?, ©2009Slide 4

5. The Safety Life Cycle 7 7 6 5 4 3 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Hazard Identification 1 1 2 Are You Ready for an SIS?, ©2009Slide 5

6. The Safety Life Cycle 7 7 6 5 4 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Risk Assessment 1 1 3 Are You Ready for an SIS?, ©2009Slide 6

7. The Safety Life Cycle 7 7 6 5 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Risk Tolerance Criteria Confirmation 1 1 4 Are You Ready for an SIS?, ©2009Slide 7

8. The Safety Life Cycle 7 7 6 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Risk Reduction Allocation 1 1 5 Are You Ready for an SIS?, ©2009Slide 8

9. The Safety Life Cycle 7 7 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Safety Function Definition 1 1 6 Are You Ready for an SIS?, ©2009Slide 9

10. The Safety Life Cycle 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Safety Function Specification 1 1 7 Are You Ready for an SIS?, ©2009Slide 10

11. The Safety Life Cycle 7 7 6 5 4 3 2 2 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Reliability Verification 1 1 8 Are You Ready for an SIS?, ©2009Slide 11

12. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Mechanical/ Electrical/ Structural Detailed Design 1 1 Are You Ready for an SIS?, ©2009Slide 12

13. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 3 4 5 6 Analysis Implementation Operation Software Configuration 1 1 2 Are You Ready for an SIS?, ©2009Slide 13

14. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 2 3 4 5 6 Analysis Implementation Operation Equipment Build 1 1 3 Are You Ready for an SIS?, ©2009Slide 14

15. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 3 2 3 4 5 6 Analysis Implementation Operation Factory Acceptance Testing 1 1 4 Are You Ready for an SIS?, ©2009Slide 15

16. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 4 3 2 3 4 5 6 Analysis Implementation Operation Construction/ Installation 1 1 5 Are You Ready for an SIS?, ©2009Slide 16

17. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 5 4 3 2 3 4 5 6 Analysis Implementation Operation Site Acceptance Testing 1 1 6 Are You Ready for an SIS?, ©2009Slide 17

18. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Validation 1 1 7 Are You Ready for an SIS?, ©2009Slide 18

19. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Training 1 1 8 Are You Ready for an SIS?, ©2009Slide 19

20. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 1 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Pre-Startup Safety Review 1 1 9 Are You Ready for an SIS?, ©2009Slide 20

21. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 9 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation 1 1 1 Are You Ready for an SIS?, ©2009Slide 21

22. The Safety Life Cycle 7 7 6 5 4 3 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation Training 1 1 2 Are You Ready for an SIS?, ©2009Slide 22

23. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 4 5 6 Analysis Implementation Operation Proof Testing 1 1 3 Are You Ready for an SIS?, ©2009Slide 23

24. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 5 6 Analysis Implementation Operation Inspection 1 1 4 Are You Ready for an SIS?, ©2009Slide 24

25. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 6 Analysis Implementation Operation Maintenance 1 1 5 Are You Ready for an SIS?, ©2009Slide 25

26. The Safety Life Cycle 7 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 Analysis Implementation Operation Management of Change 1 1 6 Are You Ready for an SIS?, ©2009Slide 26

27. The Safety Life Cycle 7 6 5 4 3 2 2 8 19 8 7 6 5 4 3 2 3 4 5 6 Analysis Implementation Operation De- commissioning 1 1 7 Are You Ready for an SIS?, ©2009Slide 27

28. The Analysis Phase 7 2 19 8 7 6 5 4 3 2 3 4 5 6 Implementation Operation 1 Analysis: Before starting on an SIS 7 6 5 4 3 2 8 Analysis 1 Are You Ready for an SIS?, ©2009Slide 28

29. Process Design  Process Design has the greatest influence on the need for an SIS  This includes all of the main Process Design Documents  Conceptual Design  PFDs and Heat/Material Balances  P&IDs 1 Are You Ready for an SIS?, ©2009Slide 29

30. Hazard Identification  Hazards are identified during the Process Hazard Analysis (PHA)  Preliminary PHAs  “What If?”  Checklist  Detailed PHA  HazOp (Hazard Operability Review) Are You Ready for an SIS?, ©2009Slide 30

31. HazOps: Some tips Tip 1. Take care in identifying the cause. If it’s a deviation, that normally means a failure. Tip 2. Some HazOp methods prompt an identification of frequency. If this is done, do it consistently…with or without safeguards, with or without recommendations, with or without SIFs Are You Ready for an SIS?, ©2009Slide 31

32. Risk Assessment Intolerable Risk Negligible Risk Consequence Likelihood Risk = Consequence x Likelihood Are You Ready for an SIS?, ©2009Slide 32

33. Risk Assessment  Consequence Analysis  Offsite Consequence Analysis (OCA)  Quantitative Risk Analysis (QRA)  Likelihood Analysis  Layers of Protection Analysis (LOPA) Are You Ready for an SIS?, ©2009Slide 33

34. How much risk is too much? Intolerable Risk Negligible Risk Consequence Likelihood Compare: Risk against Risk Tolerance Criteria Risk Tolerance Criteria Are You Ready for an SIS?, ©2009Slide 34

35. Risk Tolerance Criteria  May come from any of several sources  Plant policy  Corporate policy  Industry benchmarks and guidelines  Government mandates  The United States does not set tolerable risk levels or offer guidelines.  Outside consultants should not decide for you what is tolerable Are You Ready for an SIS?, ©2009Slide 35

36. ALARP: Levels in the UK 10 -3 fatalities/ work- year (worker) 10 -6 fatalities/ work-year (worker) 10 -4 fatalities/year (public) Intolerable Risk Negligible Risk ALARP or Tolerable Risk Region 10 -6 fatalities/year (public) Are You Ready for an SIS?, ©2009Slide 36

37. Factors to Consider  Number of facilities  Multi-national or not  Societal expectations Large, multinational companies tend to set levels consistent with international mandates, while smaller companies tend to operate in wider ranges and implicitly, at higher levels of risk Are You Ready for an SIS?, ©2009Slide 37

38. Risk Reduction Allocation When additional risk reduction is required  Non-instrumented IPLs  Passive components:  Dikes  Blast walls  Secondary containment  Active components:  Relief devices  Redundant equipment or installed spares  Instrumented IPLs  Control loops within the BPCS  Safety Instrumented Functions Are You Ready for an SIS?, ©2009Slide 38

39. How much risk reduction? Intolerable Risk Negligible Risk Consequence Likelihood SIL: Difference Between Risk and Risk Tolerance Criteria SIL Assignment Are You Ready for an SIS?, ©2009Slide 39

40. Safety Function Definition  Non-SIS Safety Functions (IPLs):  Scope definition  Project specification (This follows the normal project cycle)  SIS:  SIF List  SIL assignment Note: SILs are assigned to functions, not to systems Are You Ready for an SIS?, ©2009Slide 40

41. SIF List Typically includes  SIF Tag  Hazard Description  SIL Assignment/Required PFDavg  Trip conditions  Instrument tags  Set point and direction  Voting  Trip actions  Instrument tags  Trip state Are You Ready for an SIS?, ©2009Slide 41

42. Safety Function Specification  For an SIS, this is the Safety Requirements Specification – the SRS  Used to develop system quotes  Basis of detailed design  Basis of configuration  More extensive than a SIF List Are You Ready for an SIS?, ©2009Slide 42

43. The SRS – §10.3.1 “These requirements shall be sufficient to design the SIS and shall include the following:”  A list of 27 bullet items follow  The SIF List addresses five of them Are You Ready for an SIS?, ©2009Slide 43

44. The SRS – §10.3.1 Other items include  Source of demand and demand rate  Proof test intervals  Response time intervals  Energize-to-trip or de-energize-to-trip  Maximum allowable spurious trip rate  Overrides/inhibits/bypasses  Resets  Dangerous combinations Are You Ready for an SIS?, ©2009Slide 44

45. Organizing an SRS Suggested approach  General SIS Requirements  Specific SIF Requirements  Basis of Design  Policies  Procedures  Documents  Reports Are You Ready for an SIS?, ©2009Slide 45

46. General SIS Requirements Are You Ready for an SIS?, ©2009Slide 46

47. Specific SIF Requirements Are You Ready for an SIS?, ©2009Slide 47

48. Reliability Verification Two kinds of “SIL Calcs”  SIL Assignment Calculations  Consequence Analysis  Likelihood Analysis  SIL Verification Calculations  Required by standards  Use a combination of software tools and custom calculations  exida – SILVER (exSILentia)  SIS-Tech – SilSOLVER Are You Ready for an SIS?, ©2009Slide 48

49. Before starting SIS design  Process Design  Hazard Identification  Risk Assessment  Risk Tolerance Criteria Confirmation  Risk Reduction Allocation  Safety Function Definition  Safety Requirements Specification  Reliability Verification Are You Ready for an SIS?, ©2009Slide 49

50. After the SIS is installed Are there questions about:  Witnessing  Procedures  Responsibility (Vendor or customer?)  Certificates  Frequency  Training after installation (Who needs it? Who can operate?) Are You Ready for an SIS?, ©2009Slide 50