LOPA

How safe is safe-enough? How many protection layers are needed? What level of Risk Reduction is needed from each specific layer? Over estimation of the required risk reduction impacts on availability, productivity, design and implementation costs. Under estimation creates potential for losses if a hazardous event exposes inadequate protection. Layer of protection analysis (LOPA) is a powerful analysis for assessing the adequacy of protection layers used to mitigate process risk.

With decades of experience in safety engineering, Pilz have refined and evolved a Layer of Protection Analysis (LOPA) methodology to achieve rational and objective judgements on the safeguards required in a process. The Pilz LOPA procedure will critically analyse possible protection layers finding the required level of safety in a cost-effective & production-conscious manner. The LOPA process will provide documented technical justification for all decisions made and will clearly determine specific protection layer attributes, safety functions and required safety integrity levels.

• Identify and develop different scenarios of risk, based on each cause and consequence pair, originating from HAZOPs/Risk Assessments and related documentation
• For each scenario, identify and evaluate the consequence and calculate the associated frequency and severity
• Identify independent protection layers (IPL) and calculate their probability of failure on demand (PFD)
• Consider customer corporate guidelines, international standards such as IEC61508 and IEC 61511 and best practice to make "risk decision(s)"
• Determine the resulting safety integrity level (SIL) where a safety instrumented function (SIF) is required with an IEC 61508 compliant approach
• Identify a clear basis of safety for all high consequence scenarios within the project scope

• Achieve compliance with international standards including IEC 61508 / IEC 61511 and national legislation
• Obtain a quick and cost effective determination of critical safety requirements
• Build full confidence that your design and implementation team have an accurate and detailed specification
• Add clear and concise reports to your process safety records