Sustained long-term reliability of processing facilities is critical to profitability and competitiveness. For this reason, facilities routinely schedule turnarounds, where a section of an industrial plant or the entire facility is shut down to perform major maintenance and/or repair operations, as well as to inspect, test, and replace process materials and equipment. These planned events also provide owner-operators with the opportunity to perform debottlenecking, process upgrades, and capital project improvements while the unit or facility is offline. Inconsistent methods for screening turnaround and maintenance work can lead to missed opportunities for risk reduction and a poor return on investment. Risk-Based Work Selection (RBWS) is a systematic process for prioritizing turnaround and maintenance work using Risk to screen individual worklist items to ensure they are justified by either HSE risk reduction or Financial Benefit to Cost Analysis. When properly executed, RBWS can help owner-operators optimize the scope, cost, and duration of major turnarounds while maintaining safe and reliable operations.
Risk-Based Work Selection (RBWS) Process
The risk-based work selection process utilizes risk-based methodology (e.g., risk-based inspection (RBI) or other risk-based analysis methods) to help owner-operators identify and prioritize work for maintenance outages, turnarounds, and capital projects. This methodology provides a semi-quantitative basis to justify inclusion or rejection of worklist items, taking into consideration the Health, Safety, Environmental, and Economic risks.
The RBWS process should cover all major equipment types scheduled for a major unit turnaround, including fixed equipment, piping, valves, fired heaters, rotating equipment, instrumentation and electrical systems, infrastructure, and flare systems. Once the equipment is identified as deserving of attention, various options (e.g., change in materials of construction, OEM, etc.) can be vetted to determine optimal recommended actions based on the risk versus reward anticipated for taking or not taking any action.
For fixed equipment, RBWS utilizes RBI data, where needed, to validate or reject turnaround tasks that are included in the turnaround worklist. However, while RBI assessments focus on fixed equipment integrity and loss of containment, the RBWS methodology supplements these assessments with consideration of failures and consequences in vessel internals, which may cause an unplanned outage and impact on equipment reliability. As risk is the combined consideration of probability and consequence of failure or an undesirable outcome, it is important to include other potential consequences of interest (e.g. loss of production, injuries, environmental damage, replacement costs, time to repair, damaged reputation and public image, etc.).
As a hybrid of RBI, one might reference API RP 580 for modeling ideas, but as API RP 580 points out for risk-based inspection, there is no one correct methodology for accomplishing an effective RBWS and there may be many different approaches utilized.
6 Key Elements of RBWS Effectiveness
The effectiveness of Risk-Based Work Selection is critically dependent upon the following factors:
- Turnaround work requests that are well-defined with scope details, justifications, and cost data.
- A cross-functional team (CFT) possessing the appropriate skills and experience that is fully engaged in the RBWS decision making process. This CFT should include Operations, Process, Inspection, Turnaround Planning, and Equipment specialists.
- Subject matter experts who are available to provide input, as needed.
- An experienced facilitator who guides the CFT in executing the RBWS process.
- Proper documentation of the CFT’s risk-based decisions on inclusion/rejection of worklist items.
- A database for storing the RBWS results which can be easily shared with the turnaround planners.
References
- Radhakrishnan, A., “Risk Based Work Selection (RBWS) - A Focused Process for Achieving Turnaround Excellence,” published September 17, 2019, https://inspectioneering.com/blog/2019-09-17/8540/risk-based-work-selection--a-focused-process-for-achieving-turna.
- Radhakrishnan, A., “Risk Based Work Selection (RBWS) - An Essential Step for Turnaround Work Scope Optimization,” published October 3, 2019, https://inspectioneering.com/blog/2019-10-03/8542/risk-based-work-selection-rbws--an-essential-step-for-turnaround.
- King, A., “Risk Based Work Selection (RBWS) - Choosing the Right Software Tool,” published February 11, 2020, https://inspectioneering.com/blog/2020-02-11/8592/risk-based-work-selection-rbws--choosing-the-right-software-tool.
Relevant Links
Topic Tools
Share this Topic
Contribute to Definition
We welcome updates to this Integripedia definition from the Inspectioneering community. Click the link below to submit any recommended changes for Inspectioneering's team of editors to review.
Contribute to Definition
