Technique qualifications are conducted using a range of a single type-and-mode of degradation, e. g. circumferential outside diameter stress corrosion cracking (ODSCC). Detection capabilities of techniques are documented using a binomial distribution for determining a minimum probability of detection at a given confidence level. Sizing performance is measured against a measured value spanning the range of interest from minimum to maximum. Several performance indices are provided, such as, correlation coefficient, RMS error and error of regression.

The personnel error is derived primarily from the Qualified Data Analyst (QDA) program. The results from 286 analysts have been reviewed and compiled for several of the techniques commonly used. The process uses qualified techniques to determine the analyst probability of detection as well as the variability associated with depth sizing. For techniques not included in the QDA a site specific performance demonstration can be utilized to acquire the information needed.

The results of the performance are validated against plant conditions and a system error is generated at a mean confidence level. The results are then factored into the condition monitoring and operational assessments that are used for determining the past performance and future operation of the steam generators.