non-ionizing radiation

(noun)

Radiation that does not cause atmospheric ionization; electrically neutral radiation.

Related Terms

Examples of non-ionizing radiation in the following topics:

  • Ultraviolet Light

    • Most ultraviolet is classified as non-ionizing radiation.
    • However, the entire spectrum of ultraviolet radiation has some of the biological features of ionizing radiation, in doing far more damage to many molecules in biological systems than is accounted for by simple heating effects (an example is sunburn).
    • These properties derive from the ultraviolet photon's power to alter chemical bonds in molecules, even without having enough energy to ionize atoms.
    • Consequently, 99% of the solar UV radiation reaching the Earth's surface is UV-A.
    • An overexposure to UVB radiation can cause sunburn and some forms of skin cancer .

  • Emission Topography

    • PET scanning is non-invasive, but it does involve exposure to ionizing radiation.
    • The total dose of radiation is significant, usually around 5–7 mSv.
    • However, in modern practice, a combined PET/CT scan is almost always performed, and for PET/CT scanning, the radiation exposure may be substantial—around 23–26 mSv (for a 70 kg person—dose is likely to be higher for higher body weights).
    • When compared to the classification level for radiation workers in the UK of 6 mSv, it can be seen that use of a PET scan needs proper justification.

  • Dosimetry

    • Radiation dosimetry is the measurement and calculation of the absorbed dose resulting from the exposure to ionizing radiation.
    • Radiation dosimetry is the measurement and calculation of the absorbed dose in matter and tissue resulting from the exposure to indirect and direct ionizing radiation.
    • There are several ways of measuring the dose of ionizing radiation.
    • Outside the United States, the most widely used type of personal dosimeter is the film badge dosimeter, which uses photographic emulsions that are sensitive to ionizing radiation.
    • Non-SI units are still prevalent as well: absorbed dose is often reported in rads and dose equivalent in rems.

  • Therapeutic Uses of Radiation

    • Radiation therapy uses ionizing radiation to treat conditions such as hyperthyroidism, cancer, and blood disorders.
    • Radiation therapy involves the application of ionizing radiation to treat conditions such as hyperthyroidism, thyroid cancer, and blood disorders.
    • Ionizing radiation works by damaging the DNA of exposed tissue, leading to cellular death.
    • Radiation therapy is in itself painless.
    • Radiation therapy of the pelvis.

  • Radiation Detection

    • A radiation detector is a device used to detect, track, or identify high-energy particles.
    • A radiation detector is a device used to detect, track, or identify high-energy particles, such as those produced by nuclear decay, cosmic radiation, and reactions in a particle accelerator.
    • Different types of radiation detectors exist ; gaseous ionization detectors, semiconductor detectors, and scintillation detectors are the most common.
    • Gaseous ionization detectors use the ionizing effect of radiation upon gas-filled sensors.
    • A scintillation detector is created by coupling a scintillator -- a material that exhibits luminescence when excited by ionizing radiation -- to an electronic light sensor, such as a photomultiplier tube (PMT) or a photodiode.

  • Medical Imaging and Diagnostics

    • Radiation therapy uses ionizing radiation to treat conditions such as hyperthyroidism, cancer, and blood disorders.
    • Radiation therapy involves the application of ionizing radiation to treat conditions such as hyperthyroidism, thyroid cancer, and blood disorders.
    • Ionizing radiation works by damaging the DNA of exposed tissue, leading to cellular death.
    • Radiation therapy is in itself painless.
    • Radiation therapy of the pelvis.

  • Biological Effects of Radiation

    • Ionizing radiation is generally harmful, even potentially lethal, to living organisms.
    • Ionizing radiation is generally harmful, even potentially lethal, to living organisms.
    • Some effects of ionizing radiation on human health are stochastic, meaning that their probability of occurrence increases with dose, while the severity is independent of dose.
    • Quantitative data on the effects of ionizing radiation on human health are relatively limited compared to other medical conditions because of the low number of cases to date and because of the stochastic nature of some of the effects.
    • Two pathways of exposure to ionizing radiation exist.

  • Gamma Rays

    • Gamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency and therefore high energy.
    • Gamma rays are ionizing radiation and are thus biologically hazardous.
    • Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900, while studying radiation emitted from radium during its gamma decay.
    • Originally, the electromagnetic radiation emitted by X-ray tubes almost invariably had a longer wavelength than the radiation (gamma rays) emitted by radioactive nuclei.
    • All ionizing radiation causes similar damage at a cellular level, but because rays of alpha particles and beta particles are relatively non-penetrating, external exposure to them causes only localized damage (e.g., radiation burns to the skin).

  • Problems

    • An optically thin cloud surrounding a luminous object is estimate to be 1 pc in radius and to consist of ionized plasma.Assume that electron scattering is the only important extinction mechanism and that the luminous object emits unpolarized radiation.
    • A particle of mass $m$ and charge $q$ moves in a circle due to a force ${\bf F} = -\hat{\bf r} \frac{q^2}{r^2}.$ You may assume that the particle always moves non-relativistically.
    • What is the power radiated as a function of ${r }$ ?
    • Consider ionized hydrogen gas.Each electron-proton pair has a mass more or less equal to the mass of the proton ($m_p$) and a cross section to radiation equal to the Thompson cross-section ($\sigma_T$).
    • The radiation pressure is given by outgoing radiation flux over the speed of light.

  • Radiation from Food

    • Food irradiation is a process of treating a food to a specific dosage of ionizing radiation for a predefined length of time.
    • Food irradiation is a process of treating a food to a specific dosage of ionizing radiation for a predefined length of time.
    • In this mode the water in the pool absorbs the radiation.
    • Still, there is some controversy in the application of irradiation due to its novelty, the association with the nuclear industry, and the potential for the chemical changes to be different than the chemical changes due to heating food (since ionizing radiation produces a higher energy transfer per collision than conventional radiant heat).
    • Food and Drug Administration regulations to show a food has been treated with ionizing radiation