Guidelines for Initiating Events and Independent Protection Layers in Layer of Protection Analysis

The book is a guide for Layers of Protection Analysis (LOPA) practitioners. It explains the onion skin model and in particular, how it relates to the use of LOPA and the need for non-safety instrumented independent protection layers. It provides specific guidance on Independent Protection Layers (IPLs) that are not Safety Instrumented Systems (SIS). Using the LOPA methodology, companies typically take credit for risk reductions accomplished through non-SIS alternatives; i.e. administrative procedures, equipment design, etc. It addresses issues such as how to ensure the effectiveness and maintain reliability for administrative controls or “inherently safer, passive” concep…