The main purpose of LOPA study is to identify the countermeasures available against the potential consequences of a particular risk. This study analyse the system, and identify, using a quantitative approach, the mitigation measures against the hazard under study. LOPA is a study developed on the basis of a risk identification analysis (like HAZOP). The countermeasures or ‘protective layers’, must be independent to be effective.
LOPA addresses the key questions
- “How safe is safe enough?”
- “How many independent protection layers are needed?” and
- “How much risk reduction should each layer provide?”
Main goal of LOPA is to determine if there is sufficient protection, i.e., if the risk can be tolerated. The term protection layer is used to mean a grouping of equipment and/or administrative and procedural controls that functions in concert with other layers to control process risk, e.g. the barrier layer, or an individual protection measure, e.g. a dike (bund).
• LOPA establishes the company risk tolerance criteria
• Identify the hazards and consequence of concern
• Establish the boundaries for the consequence of concern
• Identify the initiating events and the initiating event frequencies
• The countermeasures or ‘protective layers’, must be independent to be effective.
Layers included in LOPA
• Layer 1: Process Design (e.g. inherently safer designs);
• Layer 2: Basic controls, process alarms, and operator supervision;
• Layer 3: Critical alarms, operator supervision, and manual intervention;
• Layer 4: Automatic action (e.g. SIS or ESD);
• Layer 5: Physical protection (e.g. relief devices);
• Layer 6: Physical protection (e.g. dikes);
• Layer 7: Plant emergency response; and not shown
• Layer 8: Community emergency response
Location
Address
KELVN International Safety Services Pvt. Ltd.,
Cynosure Enterprises Building, 2nd Floor, Plot No.3, Road No.12, TSIIC Tech Park, IDA Nacharam, Hyderabad-500076, Telangana.
Phone: +91 9440408111.
Email: info@kelvn.in
