The deterministic method uses more extensive inspection data to quantify the remaining thickness of the bottom. Average and maximum depth of internal and underside pitting. Maximum internal and underside pitting rates and maximum general corrosion rate. Average depth of general corrosion. The time until the next inspection.
Current trends appear to be directed toward increased use of the deterministic approach.
From an evaluation standpoint, it would be ideal to have a complete thickness map of the bottom. However, it would be expensive to perform the ultrasonic inspection that is necessary to do that, and such an extensive survey is not necessary. We won't go into theory of how MFE equipment works here. The MFE equipment will identify any locations that are thinner than the threshold setting, but it will not quantify the thickness. The thickness data are then used to perform a deterministic evaluation of the bottom.