#1304 - Layer of Protection Analysis (LOPA)

Course Objective

Upon completion of this course, attendees will be able to apply the new and powerful LOPA cost-effective risk assessment technique. LOPA is a semi-quantitative tool that uses rigorous rules to analyze scenarios and assess the associated risk. Various risk tolerance criteria are presented and discussed together with numerous worked examples to demonstrate the technique. Additional uses for LOPA (including identification of safety critical equipment, risk-based maintenance and training, etc.) are also discussed.

Who Should Attend?

• Individuals who are responsible for managing corporate process safety/risk assessment functions and who wish to assess the potential advantages offered by LOPA.
• Individuals who are performing process hazard evaluations or risk assessments.

Attendees should already have a basic understanding of process hazard evaluation techniques (See Course No. 1303)

Course Description

Introduction - Process Safety Management

• Risk
• Process Safety Management Systems
• Corporate Systems

Part I - Introduction to LOPA

• What is LOPA?
• Process Hazard Analysis/Risk Assessment Tool
• Recently Developed
• Semi Quantitative
• Cost Effective
• Methodology
• Consequence Identification
• Scenario Development
• Initiating Event Frequency
• Enabling Event Probability
• Baseline Risk
• Safeguards
• Independent Protection Layers
• Objective Risk Tolerance Criteria
• Documentation
• Uses for LOPA
• Process Hazard Analysis
• Risk Assessment
• Risk Tolerance Decisions
• Identification of Layers of Protection/Safeguards
• Interlock Classification
• Identification of "Safety Critical" Equipment and Actions
• Developing "Inherently Safer" Designs
• Management of Change
• Risk Based Inspection/Maintenance
• Training
• Incident Investigations
• Emergency Isolation Valve Requirements

Part II - Consequences

• Consequences of Interest (Loss of Containment, Releases, Explosions, Fires)
• Consequence Type
• Release Size/Characterization
• Injury/Fatality Estimate
• Detailed Injury/Fatality Estimate
• Loss of Production
• Business Loss
• Advantages/Disadvantages of Choices

Part III - Developing Scenarios

• LOPA Scenarios and Components
• Identifying Scenarios
• Analysis and Modification

Part IV - Initiating and Enabling Events

• Types of Initiating Event (External Equipment, Equipment Failures, Human Failures)
• Enabling Events/Conditions
• Failure Rate Data
• Industry Data
• Company Experience
• Vendor Data
• Calculation
• Selection, Understanding, and Frequency From Failure Rate Data
• Baseline Risk and Time at Risk

Part V - Independent Protection Layers (IPL)

• Definition of an IPL
• Difference Between Safeguard and IPL
• IPL Rules
• Probability of Failure on Demand (PFD)
• Examples and Characteristics of IPLs
• Prevention/Mitigation of IPLs

Part VI - Calculating Frequency of Scenarios

• Calculation Methods
• Multiple Scenarios
• Adjustment of Frequency for Additional Outcome (Flammable Effects, Toxic Effects, Exposure, Injury/Fatality)
• Calculating Risk
• High Initiating Event Frequency Scenarios

Part VII - Decision Making Using LOPA

• Risk Tolerance Criteria
• Expert Judgement
• Cost/Benefit Considerations

Part VIII - Documentation

• Self Documenting Method
• Typical Documentation Sheet
• Uses of LOPA Documentation

Part IX - Implementing LOPA

• Is Company Ready for LOPA?
• When LOPA Should Be Used
• Implementation

Part X - Other Applications for LOPA

• Identification of “Safety Critical Equipment and Procedures”
• Management of Change
• Risk Based Mechanical Integrity/Inspection/Maintenance
• Risk Based Operator Training
• Emergency Response
• Determine Credible Over-Pressure Scenarios
• Evaluate Facility Siting Risks
• Evaluate Need for Emergency Isolation Valve
• Bypassing Safety Systems
• Incident Investigations
• Capital Planning/Optimization

Part XI - Advanced LOPA Topics

• Multiple IPLs in Single Basic Process Control System
• Summation of Risk for Multiple Scenarios
• Development of F/N Curves
• Operator Response Issues
• Normal Operations as “Tests” of IPL Components
• Focused Fault Tree/Event Tree Analysis of IPL Components

Part XII - Worked Example 1 (Overflow from Tank Protected by Dike)

• Examines analysis of two scenarios involving overfilling tanks protected by dikes. Demonstrates application of the LOPA methodology for relatively simple scenarios. Presents results using four different LOPA risk tolerance criteria.

Part XIII - Worked Example 2 (Exothermic Batch Reactor)

• Examines multiple scenarios associated with exothermic batch reactor. Provides a more complex example of the application of LOPA for multiple scenarios. Provides detailed discussion of IPL issues involving effectiveness and independence.

Course Duration - Base course, 2 days

(3 days with additional solved examples demonstrating the technique)