ISO
ISO 17637
Non-destructive Testing of Welds — Visual Testing of Fusion-welded Joints
Visual examination treated as a method with requirements rather than as looking at something: access, illumination levels, viewing angle and distance, surface condition and the examiner's vision. Worth knowing because visual is the examination applied to one hundred per cent of welds, which makes it the one that finds the most and the one most often done informally.
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