What is not an accepted technique for NDT (Non-Destructive Testing)?

Non-Destructive Testing (NDT) involves various techniques used to evaluate the properties of a material, component, or system without causing damage. The correct answer indicates that permeation is not an accepted technique for NDT.

Radiographic testing uses X-rays or gamma rays to produce images of the internal structures of a component, revealing flaws such as cracks or voids. Ultrasonic testing employs high-frequency sound waves to detect internal flaws and measure material thickness. Infrared testing, on the other hand, involves detecting variations in temperature on the surface of materials, which can indicate issues like insulation failures or hot spots.

Permeation does not align with standard techniques used in NDT. It's typically associated with assessing the movement of molecules through materials and is often used in contexts like gas permeability testing in materials science rather than in NDT practices. Hence, selecting permeation highlights a lack of alignment with the principles and established methods of NDT.