Introduction

Reliability of NDE is difficult to quantify. In addition, it is not even clear what we actually mean by NDE reliability. For hardware, as an example, terms exist to quantify reliability of components, such as MTBF or Mean Time Between Failures. In reliability of NDE, such a term does not exist.

In this paper, we will discuss what acceptance criteria have to do with NDE reliability, especially when mechanized ultrasonic inspection systems are used, and why there is a need to develop such criteria for pipeline girth weld defects. In a separate paper by Mr. Forli of Det Norske Veritas, the subject of "how to develop such criteria" has been addressed. He will describe a joint industry project, now being initiated, that has the objective to develop and validate such criteria.