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Hazard EvaluationProcedures UPDATE

By Review of CCPS bookGuidelines for Hazard Evaluation Procedures, Third Edition

(Purchase Book from www.wiley.com)by

N. Sankaran – UOP - Honeywell

AIChE Midwest Regional Conference-Sept. 2008University of Illinois (UIC) Chicago

*The views and opinions expressed in this presentation are those of the author and do not represent those of UOP LLC or Honeywell International Inc.

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Historical

Dec. 3, 1984 – Catastrophic toxic release of MIC at Bhopal, India over 100,000 injured.1985 – Industry leaders asked AIChE to lead effort to eliminate such catastrophic events.March, 1985 – CCPS formed to

Advance Process Safety technologyServe as Process Safety resourceFoster – P.S. knowledge in EducationPromote – Process Safety as key value

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Historical (cont’d)

First step forward – write a book on “Guidelines for Process Hazard Evaluation Procedures”Mother of all future project effortsDedicated to Tom Cararody – 1st Director

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Guidelines for HEP Book

Keeps Process Engineers updated on the effective methodologies that process safety demands.Includes information not included in previous editions, giving a comprehensive overview of this topic area.Almost 200 pages of worked examples are included to facilitate understanding.

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Guidelines for HEP Book(cont’d)

ContentsHazard Evaluation Procedures – 9 chaptersWorked Examples – 13 chaptersAppendices – FiveComprehensive References

(Purchase Book from www.wiley.com)

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Progress in 23 Years

Product of various company sponsor groupsNational & International interactionForms integrated companion to other AIChE guidelines / publications

DetailedKept-Introductory

90 glossary items

15 glossary items

150 tables6 tables80 figures22 figures550 pages120 Pages

20081985

3rd Edition1st Edition

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HEP-3 GlossaryBasic process control system (BPCS): A system that responds to input signals from the process and its associated equipment, other programmable systems, and/or from an operator, and generates output signals causing the process and its associated equipment to operate in the desired manner and within normal production limits.Common cause failure: The occurrence of two or more failures that result from a single event or circumstance.Hazard evaluation: Identification of individual hazards of a system, determination of the mechanisms by which they could give rise toundesired events, and evaluation of the consequences of these events on health (including public health), environment, and property. Uses qualitative techniques to pinpoint weaknesses in design and operation of facilities that could lead to incidents.Layer of protection: A physical entity supported by a management system that is capable of preventing an initiating cause from propagating to a specific loss event or impact.Worst credible case: The most severe incident considered plausible or reasonably believable.

Illustrate:Precise & thorough – adopted in other guidelinesAbove illustrate interaction with other disciplines

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Importance of HEP-3

Unprecedented interest in hazard evaluationPrevention of incidents, economic impactsStriving for zero accidentsPublic/Governmental agency interestProcess Safety ManagementLaws & Regulations

OSHA – 29CFR 1910.119Clean Air Act – 49 CFR.68International Standards – IEC-61511 (ANSI/ISA-84.00

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Changes in 3rd Edition

New section added on Inherent Safety Review (p.64)

Reorganized into Non-scenario based (Ch.4 checklists)and scenario based (Ch.5 HAZOPs) methodologiesScenario Risk Estimation (Ch.7)

Hazard Evaluation as applied to:Procedure Based OperationsProgrammable SystemsFacility SitingHuman Factors

Emphasis on Process Life Cycle considerationsAdditional checklists & forms in Appendix A

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Interrelation of Book Chapters

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H.E. OverviewEffort to identify/analyze hazardous situations associated with processes (11)Identify weaknesses in designs & operation of facilities which can lead to releases, fires, explosionsNeeded to improve safety & manage risksCompliments traditional Industrial Safety & HealthCornerstone of the PSM programUsed in investigation of causes of accidentsManaging change to processesIdentify critical equipment & special needs (M, I, T, etc.)

Should be performed throughout Life Cycle of Process(De, D, C, O DC)

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H.E. Overview (cont’d)

Two Parts of BookPart 1 – (Page 1-292)

Specific steps to perform HE using 11 techniquesSome more common than others

Part 2 – (Page 292-460 pages)Examples to assist in developing scope, organize, lead and document hazard analysis

Benefits based on experience of many PS Professionals

3 x 30 x 25 - 2,250 years

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Benefits of Hazard Evaluation (12)

Fewer incidents over life of processReduced consequencesImproved emergency responseImproved understanding of process and trainingMore efficient & productive operationsImproved regulatory/community relations

Need significant investment over life of facility

LimitationsAnalysis never complete/perfectResults cannot be verifiedBased on present subjective judgementBased on existing knowledge

HE is an essential to reduce process risksMaintain process safety cultureEnsures compliance with C, S, R, LEstablishes/enhances organizational competence

Maintains interaction among all stakeholders (E, C, N)

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Introductory (Ch.1)

Hazard Evaluation – 1st steps in managing process risksPrevents Episode Events – fires, releases, explosionsHistorically handled by good engineering design/operating practicesHE focuses on equipment failures, software problems, human errors, external factorsFor High Quality – continued effort of multi-disciplinary groupsIdentify if more detailed methods are needed – LOPA, CPQRAGuidance on HI, Select Methods, How to Use, ImplementationLimitations of Hazard Evaluation (p.31)

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Process Risk Management

As Related to PSEvaluate hazards and risk (Hazard Analysis)Manage the Risk (9 items-Op. Procedures-17)Learn from Experience (metrics, audits)

Aspects of Risk Management

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Anatomy of a Loss EventElements of Loss Events

Process hazards (24), initiating causes (18), incident causes (10)-p.19Normal, abnormal, emergency stages of an event

Hazard Evaluation Regulations29 CFR 1910.119 – Process Safety Management40 CFR 68 – EPA Risk Management Program

Limitations of Hazard Evaluations (31)

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Preparation for HE (Ch.2)

Success of entire project is dependent on adequate preparationAn infrastructure to support HEVarious phases of process have different objectives (p.37)Scope and boundariesInformation requirements (p.40)Sept-up project on softwareSkills – Leader, ScribeOther professionals needed for team (p.44)Team leader responsibilities (p.46)Initial session important – process overview, facility walk-down, etc.

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Information Needs for HEInformation needs for HE during Project Life Cycle(p.39)

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Hazard Identification (Chapter 3)

First part of hazard evaluationTypes of consequences – human, environmental, economic (52)Material property data for HazID – (Pyrophonic) p.53Hazardous compounds (Acids) p.55Chemical interaction matrix p.57Hazard Identification results (hazard list) p.58Hazard Identification checklist (Polymerize) p.60Application of Inherent Safety p.65

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Inherent Safety Strategy & Application

IS design strategies – More reliable/safe than passive, active, procedural approachesFour basic strategies include:

Minimize (e.g. reduce the quantity of a hazardous materialSubstitute (e.g. substitute the hazardous material with a less hazardous materialModerate (e.g. use less hazardous conditions, a less hazardous form of a material, or facilities that minimize the impact of a release of a hazardous materialSimplifiy (e.g. design facilities that eliminate unnecessary complexity and make operating errors less likely, and that are forgiving of errors that are made)

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Application of Inherent Safety

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Non-Scenario Based HE Techniques (Ch.4)

4 TechniquesPreliminary Hazard Analysis (MIL-STD-882)Safety ReviewRelative Risk Ranking Methods (6 Index-Discussion-p.67)Checklist Analysis

Common FeaturesBroad brush look at hazardsDone during early stages of design

TypesSmall System – chemical unloading facilityLarge Process – a petroleum process

Hazard CategoriesHC-I - NegligibleHC-II - MarginalHC-III - CriticalHC-IV - Catastrophic

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Examples for Discussion

PHA - H2S feed system to a plantSafety Review - Extend life of a plant, update to current standardChecklist - DAP Process, materials, equipment, processRisk Index - Substance hazard index of various chemicals in plant

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Time Estimates (p.74)

Sample Worksheet

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Scenario Based HE Procedures

Predictive, analytical method based on incident scenarios

What-If/Checklist AnalysisHazard & Operability Slides (HAZOP)Fault-Tree Analysis (FTA)Failure Modes & Effects Analysis (FMEA)Event-Tree Analysis (ETA)Other Techniques

All 8 techniques generate/evaluate incident scenarios

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Scenario Based HE Procedures

FeaturesPerform very detailed Hazard AnalysisQualitative but can be structured for detailed studies (SIS, LOPA)Need special training and skills (FTA, ETA, etc.)Need more time and effortEach method illustrated by example

What-IfExperienced personnel brainstorming process with a series

of questions – each representing potential failure or mis-operation.

Question AreasEquipment failure, human error, external events

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Scenario Based HE Procedures

Sample worksheet structure – p.105

Typical questions – p.110

Sample HE checklist – p.111

Hazards checklist – p.113

SummaryMost commonly used methodLeast structuredCan be used at any stage of Life CycleUseful when focusing on MOC reviews

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Hazard & Operability Studies

Identify Hazards (S, H, E)Problems which prevent efficient operationDeviation of a parameter with a consequence for which safeguards are neededGuide Word + Parameter = DeviationMore + Flow = More FlowGeneral & specific parametersLibrary of deviations for specific equipment (p.117)DAP Process HAZOP example & worksheet (p.132)

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Overview of HAZOP Technique

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Overview of HAZOP Technique

Example library of relevant deviations for process section types

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FMEA-Failure Modes, Effects Analysis

Analysis of consequences of component, module or subsystem failuresBottoms up analysisSpreadsheet where FM, causes, probability of occurrence, consequences, proposed safeguards are notedExample of FM of equipment – HE (p.138)

Sample worksheet of a DAP Batch Reactor (p.139)

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Fault Tree Analysis

Starts with a TOP event & identifies causesTop down analysisIntermediate events – related to top event using logical operations such as AND andOR gatesExample of damage to reactor due to high process temperature (p.156)

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Damage to Reactor

Development of the Top event for the emergency cooling system example

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Other Techniques

Event Tree Analysis – Evaluates protective system failuresLoss of cooling to oxidation reactor – p.166

Cause – Consequence Analysis – p.167

Loss of Containment AnalysisFive other methods with references – p.173

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Selection of HE Techniques

Factors of influence areMotivation for the studyType of information availableResource availabilityAnalyst/Management preference

Typical effort needed for12 methods – Large/Small systems (p.185)

Example Flowcharts (p.190-194)

Is relevant checklist available – use CLIs detailed design info available – consider HAZOPIs the process a mechanical or electric system – consider FMEA

Integrating S, E, REL, Maint, Q & Sec into HE, combined reviews (p.204)

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Applications of HE Techniques During a Process Life Cycle

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Risk Based Adequacy of Safeguards(Ch.7)

Layer of Protection AnalysisSimplified quantitative Risk AnalysisCCPS – Concept bookFive step procedure (p.226)

Example LOPA (Runaway Reactors – p.231)

Scenario descriptionFrequency of unmitigated consequenceTotal PFD of all IPLsFrequency of mitigated consequenceRisk tolerance criteria met

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Follow-up of Hazard Evaluation

Development of Recommendation –immediate action, scheduled, further evaluationSimple Risk Matrix (p.244)

Documentation for follow-upDevelopment of Management responsesSpecial findings/sharing of informationHE results useful over Life Cycle of the plant (p.255)

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4 x 4 Risk Matrix

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Special Hazard Analysis Applications

60-70% of accidents in 2 decades occurred during non-routine modes of operations.

Hazard Analysis of Procedure-based Operations Unloading a Toxic Chemical – p.266Programmable Logic Controllers-Control of ProcessesChemical Reactivity Hazards *- Inadequate Venting of GasesCombination Methods – HAZOP/LOPAHuman Factors Study – Negative Factors Leading to Errors. P.277-9HRA – Human Reliability AnalysisFacility Siting issues *

* Separate CCPS/guideline books available

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HE Methods – Worked Examples (Ch. 10-22, p. 293-460

11 methods (e.g. Event Tree Analysis)Cover – 9 phases of Life Cycle (e.g. plant expansionsCovers 2 aspects – How to Perform; TrainingApplied to VCM – Manufacture operationsIllustrative – block flow diagrams, process descriptions, scope, worksheets, tables, checklists, discussions, observations, conclusions.Sample worksheet for every method – FMEA, p.448

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Useful Appendices (A)

Checklist items – corrosion types (464)Management of Change – Impact Evaluation List (456)Reactivity checklist – Reactivity with air (470)Inherent safety checklist – 5 categories – 3 pages (472)

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Supplemental HAZID Questions (Appendix B)

Process (20)Unit siting/layout (16)Equipment

Pressure relief (20)Piping & valves (30)Pumps (6)Compressors (6)Reactors (8)Vessels (9)HE (8)Furnaces (4)Instrumentation (23)Elec. Power (12)

Miscellaneous (2)How are equipment & piping protected from corrosion?

Operations (22)Maintenance (13)Personnel Safety (68)Environmental Protection (24)Management Issues (21)

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Hazard Evaluation Software

9 samples listedPHA - Unwin Co. - USAHAZOP - Isograph - UKPHA-PRO – Dyadem – CanadaPHA-Works – PrimaTech - USA

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Process Safety Enhancement Resources Organizations Listed

40 premier organizations listed, including AIChE-CCPS

National Safety Council - Safety Video ProgramWorld Bank – Hazard Evaluation manualUS Chemical Safety Board – Hazard InvestigationIChemE (UK) – Sister org. to AIChEUS EPA – Risk Management Program, WCS.

244 references for more detailed studies

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How Do You Participate?

How do you participate in a project like this?CCPS Member Co.Join new project sub-committeeProject examples:

Guidelines/concept booksDatabases (PERD), (PSID)Web-based Safety ProjectsSpecial Interest items

List of Current Projects (30)Benefits:

Trade knowledgeContribute diversity of experienceLesson in concensus approach

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Participation (cont’d)

New projects submitted to Technical Steering CommitteeSub-committee formed – Leader, Eng. Contractor, MembersImportance of subjects takes precedence over sales volume.

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Index1. Title Slide2. Historical (2,3)3. Guidelines for HEP Book - General Comments (4,5)4. Progress Update (6)5. Sample Glossary (7)6. Importance of HEP-3 (8)7. Changes in 3rd Edition (9)8. Interrelation of Chapters (10)9. HE Overview, Benefits (11-13)10. Introductory-Ch. 1 (14)11. Concept of Risk Management (15)12. Anatomy of a Loss Event (16)13. Preparation for HE (17)14. Information Needs (18)

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Index

15. Hazard Identification-Ch. 3 (19)16. Inherent Safety Strategy & Application (20,21)17. Non-Scenario Based Techniques (22-24)18. Scenario Based HE Procedures (25-34)19. Selection of Techniques (35, 36)20. LOPA (37)21. Follow-up of Hazard Evaluation (38, 39)22. Special Applications (40)23. Appendices (42)24. Supplemental Checklist (43)25. Software (44)26. Process Safety Organizations (43)27. Participation (46, 47)