Risk-Based Inspection (RBI) is an analysis methodology and process that requires qualitative or quantitative assessment of the probability of failure (PoF) and the consequence of failure (CoF) associated with each equipment item, piping circuits included, in a process unit. The risk-based approach requires a systematic and integrated use of expertise from the different disciplines that impact plant integrity. Risk-based methodologies enable the assessment of the likelihood and potential consequences of equipment failures.
Risk-Based Inspection (RBI) provides companies the opportunity to prioritize their equipment for inspection; optimize inspection methods, frequencies, and resources; and develop specific equipment inspection plans. This results in improved safety, lower failure risk, fewer forced shutdowns, and reduced operational costs.
A properly implemented RBI program categorizes individual pieces of equipment by their risks and prioritizes inspection efforts based on this categorization.
RBI can be used to prioritize inspection-related activities, usually by means of non-destructive examination (NDE), to reduce the uncertainties around the true damage state of the equipment and the dynamics leading to such. The resulting inspection plan may outline the type and scheduling of inspection for an asset. In addition to NDE, additional risk mitigation activities identified by an RBI assessment might include a change in material of construction, installation of corrosion resistant liners, operating condition changes, injection of corrosion inhibition chemicals, etc.
Consistency and repeatability of analysis are critical to producing an effective RBI program, as RBI is based on relative risks.