Why is X-ray inspection considered a nondestructive testing method?

X-ray inspection is classified as a nondestructive testing (NDT) method because it allows for the examination of a material's internal structure and the detection of flaws without damaging or destroying the object being tested.12

Unlike destructive testing methods, such as tensile-strength tests where the sample is consumed or altered during data collection, X-ray techniques rely on the ability of radiation to penetrate optically opaque materials. By passing a radiation beam through an object and capturing the resulting image on a detector or photographic film, inspectors can identify internal defects, such as cracks or corrosion, in finished or semifinished products that would otherwise be inaccessible to direct observation. This capability is essential for industries where materials are costly, difficult to fabricate, or must remain intact for continued use, such as in aerospace maintenance or the analysis of delicate art objects.3214