Associate Safety Professional Practice Exam

Which type of radiation is classified as non-ionizing?

1. Gamma rays

2. X-rays

3. Ultraviolet radiation

4. Beta particles

The correct answer is: Ultraviolet radiation

Non-ionizing radiation is characterized by its inability to remove tightly bound electrons from atoms or molecules. This type of radiation does not carry enough energy to ionize atoms, which distinguishes it from ionizing radiation types, like gamma rays, X-rays, and beta particles. Ultraviolet (UV) radiation falls under the category of non-ionizing radiation because, while it can cause some biological effects, it does not have sufficient energy to ionize most atoms. UV radiation can cause chemical reactions that contribute to tissue damage and other effects, such as skin burns or DNA alterations, but the fundamental nature of UV means it does not remove electrons from atoms to form ions. In contrast, gamma rays and X-rays are forms of ionizing radiation that possess higher energy levels, sufficient to ionize atoms, which increases the potential for serious biological effects. Beta particles, although they are electrons and can interact with matter, carry enough kinetic energy to ionize atoms as well. Therefore, UV radiation is distinctly recognized as non-ionizing due to its lower energy level relative to ionizing radiation types.