Usually 2x to 5x magnification for closer surface inspection.
Visual Inspection (VT) is the oldest, most widely used, and arguably the most important Non-Destructive Testing (NDT) method. In the fabrication industry, it is estimated that over 80% of inspections are performed visually. (also known as DIN EN 970 or EN 970) is the European standard that specifies the requirements for the visual inspection of fusion welds. bs en 970 visual inspectionpdf best
Inspections should be performed by competent persons (e.g., CSWIP or PCN Level 2 certified). Usually 2x to 5x magnification for closer surface inspection
"The best tool is an educated eye."
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