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

The radiation quality of a gamma-ray source is primarily determined by the isotope involved because each radioactive isotope emits gamma rays with specific energy levels and characteristics. These properties are intrinsic to the isotope itself, as different isotopes have distinct decay processes and energy spectra.

The energy of the emitted gamma rays affects how they interact with matter, their penetrating ability, and the resulting radiation dose to any material or biological tissue they encounter. Therefore, understanding the isotope being used is crucial to determining not only the quality but also the safety and effectiveness of the radiation in applications like radiographic testing.

While factors such as time of exposure, angle of incidence, and distance from the source can influence the intensity of radiation received or the extent of interaction with materials, they do not alter the fundamental energy and quality characteristics of the gamma rays being emitted from the source.