American Society for Nondestructive Testing (ASNT) Radiographic Testing Practice Test

Static marks on a radiograph, which manifest as distinct black tree-like or circular patterns, are primarily a result of improper film handling techniques. These marks occur due to the build-up of static electricity on the film surface, which can attract dust or cause the emulsion to crack during the handling process. When the film is then exposed to radiation, these static marks become visible as dark spots or patterns on the developed radiograph.

Effective film handling involves taking precautions to minimize the occurrence of static electricity, such as using anti-static equipment, handling film in a controlled environment, and ensuring that operators maintain grounding to reduce the risk of static charge accumulation. In contrast, the other options do not directly relate to the creation of these specific marks. For instance, while high humidity can affect film quality, it does not create static marks, and defective film may result in other types of issues that are not characteristic of static-related artifacts.