Visual examination

Visually examine the sample. Examine the sample with unaided eye, hand lens and/or low magnification field microscopes. Note the condition of the accessible surface documenting all sorts of anomalies, searching for cracks, corrosion damage, the presence of foreign material, erosion or wear damage, or evidence of impact or other distress. Also consider the condition of protective coatings. Manufacturing defects are important. (reference: Dr. Zee)

If pipe failure is involved, it is important to carefully measure wall thicknesses both at the failure site and some distance away from it at four locations 90 degrees apart around the pipe circumference, starting a the failure site. At the same time note the presence of any corrosion and map its general distribution.

Case example: a common copper sink drain