RBI - Risk Definitions
Risk based inspection is based on the premise that the risk of failure can be assessed in relation to a level that is acceptable, and that inspection and repair, or other actions can be used to manage the risk such that it is maintained below that acceptance limit. The risk associated with a failure is calculated as the product of probability of failure and consequence of failure.
Risk Based Inspection (RBI) uses risk as a basis for prioritizing and managing an
• Risk Based Inspection (RBI) is a method that utilizes risk as a basis for prioritizing and managing the efforts of an inspection program.
• It is well known that in the oil& gas pipeline facilities, a relatively large percentage of the risk is associated with the small percentage of equipment items.
Risk = Probability of Failure x Consequence of Failure
Driving Forces for RBI
• Increase Safety
• Reduce Cost
• Maximize Productivity
• Deal with Aging Plants
• Prevent Catastrophic Failures
• From Fixed Inspection Intervals to Flexible
– A measure of the potential for loss in terms of both the likelihood (events/year) of the incident and the consequences (effects/event) of the incident
• Risk Analysis
– The development of a quantitative estimate of risk based on engineering evaluation & mathematical techniques for combining estimates of incident likelihood and consequences
• Risk Assessment
– The process by which the results of a risk analysis (i.e., risk estimates) are used to make decisions, either through relative ranking of risk reduction strategies or through comparison with risk targets
• Risk Management
– The planning, organizing, leading and controlling of an organization’s assets and activities in ways, which minimize the adverse operational and financial effects of accidental losses upon the organization
* Helps in
– Forecasting any unwanted situation
– Estimating damage potential of such situation
– Decision making to control such situation
– Evaluating effectiveness of control measures
The probability of suffering a harm or loss. It is a combination of hazard and Probability
– Risk = Probability of occurrence of hazard X magnitude of hazard
* Risk Assessment is a systematic procedure for describing and quantifying the risk associated with hazardous substance, process, action or event.
* It involves:
– Identification of hazard
– Quantification of hazard
– Quantification of probability of occurrence of hazard
– Estimation of risk
Risk is often defined as the combination of the likelihood of a problem
occurring and the impact of the problem if it were to occur.
What is Risk Analysis?
1) Identify the possible risks that a project faces.
2) Estimate the loss to the organization if that risk occurs.
3) Choose risk mitigation strategies and calculate their cost.
4) Compare the cost of the loss to the cost of risk mitigation and
“Performing risk-based analysis on the software will allow intelligent
choices to be made regarding what tests need to be run in a time
crunch situation. It ensures that the choice between what is tested and
what is not is a conscious decision based on an understanding of the
technology and the users.”
“The magnitude of a risk is a joint function of the likelihood and impact of
the problem—the more likely the problem is to happen, and the more
impact it will have if it happens, the higher the risk associated with that
problem. Thus, testing is motivated by risk.”