API-580 Exam Dumps : API 580 - Risk Based Inspection

Section 5.3.5 of API 580 explains the nature of semi-quantitative RBI analysis:

“Semi-quantitative… is geared to obtain the major benefits of the previous two approaches (e.g. speed of the qualitative and rigor of the quantitative)… The results are usually given in consequence and probabilitycategories or as risk numbers, but numerical values may be associated with each category to permit the calculation of risk and the application of appropriate risk acceptance criteria.”

Therefore, semi-quantitative assessments often produce risk values in a numeric format, allowing comparative decision-making. This distinguishes them from purely qualitative assessments that rely on subjective categories like “High/Medium/Low.”

As stated in Section 11.4 of API 580:

“Sensitivity analysis typically involves reviewing some or all input variables to the risk calculation to determine the overall influence on the resultant risk value.”

This process helps identify which input variables most significantly affect the final risk values. Such variables are prioritized for validation and refinement to improve the quality of the analysis.

Per Section 13.3 of API 580:

“A Fitness-For-Service (FFS) assessment (e.g., API 579-1/ASME FFS-1) may be performed to determine what size flaws, if found in future inspections, would require repair or equipment replacement.”

This makes Fitness-For-Service the correct method for evaluating whether existing or predicted flaws are tolerable or require corrective action.