Radiation - Non-ionizing Radiation - Non-ionizing Electromagnetic Radiation

Non-ionizing Electromagnetic Radiation

The non-ionizing portion of electromagnetic radiation consists of electromagnetic waves that (as individual quanta or particles, see photon) are not energetic enough to detach electrons from atoms or molecules, ionizing them. These include radio waves, microwaves, infrared, and (sometimes) visible light. (Ultraviolet light, X-rays and gamma-rays are regarded as ionizing.) The occurrence of ionization depends on the energy of the individual particles or waves, and not on their number. An intense flood of particles or waves will not cause ionization if these particles or waves do not carry enough energy to be ionizing, unless they raise the temperature of a body to a point high enough to ionize small fractions of atoms or molecules by the process of thermal-ionization (this requires relatively extreme radiation energies, however).

The electromagnetic spectrum is the range of all possible electromagnetic radiation frequencies. The electromagnetic spectrum (usually just spectrum) of an object is the characteristic distribution of electromagnetic radiation emitted by, or absorbed by, that particular object.