Specialized Reviews CHAZOP, EHAZOP, Bow Tie Analysis, Layers of Protection Analysis, Safety Integrity Level, Fishbone Diagram, and Cyber Security Vulnerability Analysis
The specialized reviews of Bow Tie Analysis (BTA) Layers of Protection Analysis (LOPA) and Safety Integrity Level (SIL) which are being increasingly utilized in the industry for safety reviews, are defined and discussed in this chapter. The origin of BTAs is highlighted along with how such a review is undertaken, with a simplified diagram of its process. LOPA features are defined in order to ensure they qualify as true risk reduction applications. The description explains how probabilities are determined for the risk reduction features. For SIL reviews, the applicable standards are highlighted along with the SIL levels utilized in industry. How SIL probabilities are determined are also explained. An example of an SIL worksheet arrangement is presented. Additionally, CHAZOP (Computer Hazard and Operability Study) EHAZOP (Electrical Hazard and Operability Study) Fishbone Diagram, and Cyber Security Vulnerability Analysis are described.