Although the risk management principles and concepts that RBI is built on are universally applicable, this RP is specifically targeted at the application of RBI in the hydrocarbon and chemical process industry.
Flexibility in Application
Because of the broad diversity in organizations' size, culture, federal and/or local regulatory requirements, this RP offers users the flexibility to apply the RBI methodology within the context of existing corporate risk management practices and to accommodate unique local circumstances. The document is designed to provide a framework that clarifies the expected attributes of a quality risk assessment without imposing undue constraints on users. This RP is intended to promote consistency and quality in the identification, assessment, and management of risks pertaining to material deterioration, which could lead to loss of containment.
Many types of RBI methods exist and are currently being applied throughout industry. This document is not intended to single out one specific approach as the recommended method for conducting an RBI effort. The document instead is intended to identify and clarify the essential elements of an RBI analysis and program.
Mechanical Integrity Focused
The RBI process is focused on maintaining the mechanical integrity of pressure equipment items and minimizing the risk of loss of containment due to deterioration. RBI is not a substitute for a PHA or hazard and operability assessment (HAZOP). Typically, PHA risk assessments focus on the process unit design and operating practices and their adequacy given the unit's current or anticipated operating conditions. RBI complements the PHA by focusing on the mechanical integrity related damage mechanisms and risk management through inspection. RBI also is complementary to RCM programs in that both programs are focused on understanding failure modes, addressing the modes and therefore improving the reliability of equipment and process facilities.
The following types of equipment and associated components/internals are covered by this document.
- Pressure Vesselsâ€”All pressure containing components.
- Process Pipingâ€”Pipe and piping components.
- Storage Tanksâ€”Atmospheric and pressurized.
- Rotating Equipmentâ€”Pressure containing components.
- Boilers and Heatersâ€”Pressurized components.
- Heat exchangers (shells, floating heads, channels, and bundles).
- Pressure-relief devices
Equipment Not Covered
The following equipment is not covered by this document:
- instrument and control systems,
- electrical systems,
- structural systems,
- machinery components (except pump and compressor casings).
However, these systems and components may be covered by other types of RBI or risk assessment work processes such as RCM.
The primary audience for this RP is inspection and engineering personnel who are responsible for the mechanical integrity and operability of equipment covered by this RP. However, while an organization's inspection/materials engineering group may champion the RBI initiative, RBI is not exclusively an inspection activity. RBI requires the involvement of various segments of the organization such as engineering, maintenance and operations. Implementation of the resulting RBI product (e.g. inspection plans, replacement/upgrading recommendations, other mitigation activities, etc.) may rest with more than one segment of the organization. RBI requires the commitment and cooperation of the total operating organization. In this context, while the primary audience may be inspection and materials engineering personnel, other stakeholders who are likely to be involved should be familiar with the concepts and principles embodied in the RBI methodology to the extent necessary for them to understand the risk assessment process and to be able to accept the results.
The purpose of this document is to provide users with the basic elements for developing, implementing, and maintaining a risk-based inspection (RBI) program. It provides guidance to owners, operators, and designers of pressure-containing equipment for developing and implementing an inspection program. These guidelines include means for assessing an inspection program and its plan. The approach emphasizes safe and reliable operation through risk-prioritized inspection. A spectrum of complementary risk analysis approaches (qualitative through fully quantitative) can be considered as part of the inspection planning process. RBI guideline issues covered include an introduction to the concepts and principles of RBI for risk management; and individual sections that describe the steps in applying these principles within the framework of the RBI process include:
- understanding the design premise;
- planning the RBI assessment;
- data and information collection;
- identifying damage mechanisms and failure modes;
- assessing probability of failure (POF);
- assessing COF;
- risk determination, assessment, and management;
- risk management with inspection activities and process control;
- other risk mitigation activities;
- reassessment and updating;
- roles, responsibilities, training, and qualifications;
- documentation and recordkeeping.
The expected outcome from the application of the RBI process should be the linkage of risks with appropriate inspection, process control or other risk mitigation activities to manage the risks. The RBI process is capable of generating:
1) a ranking by relative risk of all equipment evaluated;
2) a detailed description of the inspection plan to be employed for each equipment item, including:
â€” inspection method(s) that should be used [e.g. visual, ultrasonic (UT), radiography, wet flourescent magnetic particle];
â€” extent of application of the inspection method(s) (e.g. percent of total area examined or specific locations);
â€” timing of inspections/examinations (inspection intervals/due dates);
â€” risk management achieved through implementation of the inspection plan;
3) a description of any other risk mitigation activities [such as repairs, replacements or safety equipment upgrades, equipment redesign or maintenance, integrity operating windows (IOWs), and controls on operating conditions];
4) the expected risk levels of all equipment after the inspection plan and other risk mitigation activities have been implemented;
5) identification of risk drivers.