(V) How to Negotiate NDT Work in Support of Failure Analysis

NDT is useful in several aspects of failure analysis, including examining assemblies for part placement in the condition as received by the lab, looking for discontinuities such as porosity in welds and castings, finding the extent of closed cracks to facilitate developing a plan to reveal the crack surfaces, and especially for process failures of metallic parts, sorting potential "good" and "bad" parts to create reference specimens. Visual inspection is almost always the first step of the process, and the failure analyst must be aware of the differences between visual examination for failure analysis and "Visual Testing" done by NDT practitioners.

It is important to understand the qualifications of the individual who will be performing the work. Since failure analysis work is generally not being done in order to certify parts for use, many NDT technicians do not bother to perform the standard set ups that they would normally use. It's important to know before selecting the service how they will provide the data. Will you get X-ray films? JPG files? Paint lines on the part to guide future cuts?

Especially if the failure analyst is going to be having someone from an outside company do the inspections, it is important to negotiate inspection set-up to code when possible, and to engage the services of an individual certified to a Level 3 by a national standard. In general, people who have not attained the educational background to become a Level 3 in at least 2 or 3 methods are incapable of having useful discussions about such matters as "Why was this discontinuity not found at the manufacturing stage?" "What is the largest discontinuity this method could potentially miss?" Only such individuals may be relied on to explain the disadvantages and advantages of the particular methods they are using.