Essentials of Layer of Protection Analysis (LOPA)
Layer of protection analysis (LOPA) is a semi-quantitative method of risk assessment that provides the middle ground between a qualitative process hazard analysis (such as a HAZOP or What-If) and a full quantitative risk analysis. Beginning with an identified accident scenario, LOPA uses simplifying rules to evaluate initiating event frequencies, enabling events and conditional modifiers of the initiating events, independent layers of protection, and consequences to provide an order-of-magnitude estimate of risk. LOPA has also proven an excellent and widely-used approach for determining the safety integrity level necessary for an instrumented safety system, an approach endorsed in industry standards, such as ISA S84.01 and IEC 61511.
The training provides complete instruction on how to lead a LOPA, and how to integrate LOPAs with PHAs. The course includes the main topics from the Center for Chemical Process Safety (CCPS) concept book on Layers of Protection Analysis Initiating Events, and Enabling Events/Conditional Modifiers.
- Learn how and when to use LOPA.
- Learn how to develop scenarios from a qualitative hazard study (i.e. HAZOP) or from a new process/changes to a process.
- Learn how to estimate the frequency category for the initiating event of a scenario.
- Learn how to determine the consequence category for the unmitigated scenario.
- Understand how to determine which protection layers meet the criteria of independence and uniqueness as independent protection layers (IPLs).
- How to determine the risk of a LOPA scenario and how to determine if further risk reduction is warranted.
- Learn industry best practices for LOPA.