Question

Which of the following is the major drawback of using X-rays compared to gamma rays for inspecting thick materials in Radiography Test?

• A. X-rays require a higher energy source than gamma rays
• B. X-rays produce more secondary radiation, which can be hazardous
• C. X-rays can only be used for surface inspections
• D. X-rays have a higher attenuation rate in dense materials

Hint:

X-rays are absorbed more quickly in dense materials due to higher attenuation, making gamma rays better for inspecting thicker sections.

Answer 1

The Correct Option is D

In industrial radiography, X-rays and gamma rays are both used to inspect internal features of materials.
However, X-rays have a significant limitation when inspecting thick or dense materials due to their higher attenuation rate.
This means that X-rays lose their intensity more rapidly as they pass through dense materials, making them less effective for deep penetration.
Gamma rays, especially from isotopes like Iridium-192 or Cobalt-60, have higher energy and penetrate thicker sections more effectively.
Therefore, for radiographic testing of thick components (such as large castings or heavy-walled vessels), gamma rays are often preferred.