Risk-based Inspection (RBI): What You Need to Know

asset integrityMetal corrodes. It’s simply the way of life. In fact, when it comes to metal, there are 10 different primary forms of corrosion. For crude oil plants and other large industrial facilities, that corrosion can compromise the safety of thousands of people. It can also result in significant monetary losses, due to asset repairs and replacements, facility downtime, and regulatory fines.

Indeed, the American Water Works Association estimates that the nation will need $1 trillion over a 25 year period through 2035 to restore existing water system pipes that have reached the end of their useful life and to expand pipe networks to meet increasing populations.

That’s where asset integrity, , asset reliability management, and especially risk based management come in. Risk-based inspection, as opposed to condition-based inspection, is an analysis methodology that is based on calculations of the probability of failure (POF) and the consequence of failure (COF) in relation to each equipment item of a specific system.

When properly executed, RBI breaks down a facility or system for analysis piece by piece. Specifically, RBI is intended to identify risk andrisk drivers, and will also identify how far into its lifespan a piece of equipment is. RBI can be used to determine whether or not an inspection is needed, and thus, can help managers make informed business decisions. And in a regulatory environment in which compliance is of utmost importance, RBI is absolutely essential. International engineering standards, such as API RP 580 and 581; ASME PCC 3; and RIMAP, are commonly used in RBI implementation.

The main objectives of risk based inspection are as follows:

  • RBI offers a holistic, interdependent approach for managing risks.
  • Helps create a plan to reduce the risk of failure and ensure inspection techniques adhere to all relevant codes of compliance. This also increases overall health and safety of assets and systems.
  • Maximized lifespan of assets and systems, without compromising safety or reliability.
  • Prioritizes inspections based on risk, and can therefore reduce unplanned downtime.

With RBI, priority is given to items that have high probability and high consequence (high risk), rather than items which have high probability but for which failure has relatively low consequences. In short, RBI helps decision makers act proactively, rather than reacting to one disaster after another.

Who Is Risk Based Assessment Helpful For?

Risk based assessment can be done in a number of different ways, ranging from a qualitative, semi-quantitative, or quantitative. It is especially helpful in the oil, gas and petrochemical fields, as well as when examining any facilities with storage tanks, onshore pipelines and structures, and power generation components (steam turbines, heat recovery steam generators, etc). The established methodology of risk-based assessment analysis, along with asset integrity support, offers invaluable time and cost efficient management solutions.