Layer of Protection Analysis (LOPA)
LOPA is a semi-quantitative tool to establish adequacy of the protection layers against a hazard. This methodology uses Independent Protection Layers (IPLs) along with other frequency modifiers to provide an order-of-magnitude estimation of the likelihood of a given consequence. Risk acceptance and reduction, if necessary, can then be computed using corporate risk standards. If the analysis determines that additional risk reduction is required, a Safety Instrumented Function (SIF) may be identified among other safeguard considerations. LOPA provides the tool to establish the necessary Safety Integrity Level (SIL) of the SIF, which is calculated through the SIL Assignment process.
- Conducted LOPA for every major vessel in all process units of a major petroleum refinery.
- Conducted LOPA for high severity consequences in all process units of a major petroleum refinery.
- Conducted LOPA and SIL Assignment tasks for systems during the Front End Engineering Design (FEED) phase of a major methanol facility and refinery units.