According to Section 7.3 of API 580:
"The data quality has a direct relation to the relative accuracy of the RBI analysis... Although the data requirements are quite different for the various types of RBI analysis, quality of input data is equally important no matter what approach to RBI is selected." This clearly establishes that regardless of whether a qualitative, semi-quantitative, or quantitative RBI method is chosen, the quality of data must remain consistently high to ensure meaningful risk assessments.
Reference: API 580, 2nd Edition (2016), Section 7.3

As defined in API 580, Section 3.1.59:
"Risk evaluation: The process used to compare the estimated risk against given risk criteria to determine the significance of the risk." This follows from the broader risk assessment process where risk identification and analysis occur first, followed by risk evaluation.
Reference: API 580, 2nd Edition (2016), Section 3.1.59

API 580, Section 12.4 states:
"Depending on factors such as the remaining life of the equipment and type of damage mechanism, risk management through inspection may have little or no effect." Examples include:
Instantaneous failures
Equipment at end of life
Damage mechanisms not detectable through inspection
Reference: API 580, 2nd Edition (2016), Section 12.4
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API 580, Section 15.2.4:
"A qualified corrosion specialist shall be responsible for assessing the types of damage mechanisms and their applicability and severity to the equipment considering the process conditions, environment, metallurgy, age, and other relevant data." Other roles may assist but the designated responsibility lies with the corrosion specialist.
Reference: API 580, 2nd Edition (2016), Section 15.2.4
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Per Section 11.7 of API 580:
"Thresholds that divide the risk plot matrix or table into acceptable and unacceptable regions of risk can be developed. Corporate safety and financial policies and constraints or risk criteria influence the placement of the thresholds." This confirms that risk thresholds define boundaries between acceptable and unacceptable regions, not simply levels of consequence or probability.
Reference: API 580, 2nd Edition (2016), Section 11.7
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