API 580 defines RBI as a methodology that uses relative risk as a basis for prioritizing and managing the efforts of an inspection program, including recommendations for monitoring and testing. It provides focus for inspection activity to specifically address threats to the integrity of the asset and the equipment’s capacity to operate as intended. The POF and COF are assessed separately and then combined to determine risk of failure. Risk is then compared and prioritized for inspection planning and risk mitigation. Required Elements in RBI include:
- – Work Process Requirements
- – Data Requirements
- – Damage Mechanisms and Failure Modes
- – POF Analysis
- – COF Analysis
- – Evaluation of Risk
- – Output
- – RBI Reassessment and Updating
Both API 581, Risk-Based Inspection Technology or ASME PCC-3, Inspection Planning Using Risk-based Methodscan be used for risk assessment of process plant. RBI methodology addressed in both standards cover the assessment procedures for pressurized fixed equipment including pressure vessel, piping, tankage, pressure relief devices (PRDs), and heat exchanger tube bundles.Spectrum of complimentary risk analysis approaches (qualitative,semi quantitative and fully quantitative) can be considered for a facility based on purpose of the RBI assessment. Risk assessment of underground and above ground pipelines are excluded from scope of the API 581. Generally, API RP 1160 is used for risk assessment of the Hazardous Liquid Pipelines, and DNV-RP-F116 is applied for integrity management of submarine pipeline systems.
- American Petroleum Institute “API Recommended Practice 580.” American Petroleum Institute (2016).
- LifeTech Risk Based Inspection procedure, 2020.