What defines non-ionizing radiation?

Non-ionizing radiation is defined as radiation that does not carry enough energy to ionize atoms or molecules. This means that non-ionizing radiation lacks the energy necessary to remove tightly bound electrons from the orbit of an atom, which is the defining characteristic of ionization. This type of radiation includes forms such as visible light, ultraviolet light (with lower energy levels), infrared radiation, microwaves, and radio waves.

In contrast to ionizing radiation, which can cause significant chemical changes and biological damage, non-ionizing radiation is generally considered to have less potential for harm at typical exposure levels because it does not have the energy required to break chemical bonds or disrupt atomic structure. This distinction is vital in radiological safety and health physics, as it influences how we approach exposure limits and protective measures.

While non-ionizing radiation may still contribute to thermal effects (like the heat emitted by infrared radiation), its defining criterion remains its inability to ionize matter. Thus, the correct understanding of non-ionizing radiation revolves around its energy levels and their resulting biological implications.