Non-destructive testing encompasses inspection methods that evaluate material properties, detect flaws, and measure degradation without damaging the component being examined. Common NDT techniques include ultrasonic testing, radiography, magnetic particle inspection, dye penetrant, and visual examination, each suited to specific defect types and material characteristics. These methods are essential for verifying weld quality during fabrication, assessing equipment condition during turnarounds, and supporting fitness-for-service evaluations.