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1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and acronyms
5 General description
6 Benefits and limitations of Event Tree Analysis
   6.1 Benefits
   6.2 Limitations
7 Relationship with other analysis techniques
   7.1 Combination of Event Tree Analysis and Fault
        Tree Analysis
   7.2 Layer of Protection Analysis (LOPA)
   7.3 Combination with other techniques
8 Development of event trees
   8.1 General
   8.2 Steps in Event Tree Analysis
        8.2.1 Procedure
        8.2.2 Step 1: Definition of the system or
              activity of interest
        8.2.3 Step 2: Identification of the initiating
              events of interest
        8.2.4 Step 3: Identification of mitigating factors
              and physical phenomena
        8.2.5 Step 4: Definition of outcomes and quantification
        8.2.6 Step 5: Analysis of the outcomes
        8.2.7 Step 6: Uses of Event Tree Analysis Results
9 Evaluation
   9.1 Preliminary remarks
   9.2 Qualitative analysis - Managing dependencies
        9.2.1 General
        9.2.2 Functional dependencies
        9.2.3 Structural or physical dependencies
   9.3 Quantitative analysis
        9.3.1 Independent sequence of events
        9.3.2 Fault tree linking and Boolean reduction
10 Documentation
Annex A (Informative) - Graphical representation
Annex B (Informative) - Examples
   B.1 Fire incident in a nuclear power plant
        B.1.1 Introduction
        B.1.2 Screening analysis
        B.1.3 Quantitative analysis
        B.1.4 Results
   B.2 Event Tree Analysis for a level-crossing system
        B.2.1 Symbols and acronyms
        B.2.2 Objective
        B.2.3 System definition
        B.2.4 Hazard identification
        B.2.5 Event Tree Analysis
        B.2.6 Quantitative analysis
        B.2.7 Analysis of the outcomes and definition of
              necessary action
        B.2.8 Conclusion
   B.3 Fault tree linking and Boolean reduction
Bibliography

BS EN 62502