Non-ionizing radiation

File:EM-spectrum.pngDifferent types of electromagnetic radiation.

Non-ionizing radiation (or, esp. in British English, non-ionising radiation) refers to any type of electromagnetic radiation that does not carry enough energy per quantum to ionize atoms or molecules -- that is, to completely remove an electron from an atom or molecule.[1] Instead of producing charged ions when passing through matter, the electromagnetic radiation has sufficient energy only for excitation, the movement of an electron to a higher energy state. Nevertheless, different biological effects are observed for different types of non-ionizing radiation.[2][3]

Near ultraviolet, visible light, infrared, microwave, radio waves, low frequency RF and static fields are all examples of non-ionizing radiation. Visible and near ultraviolet may induce photochemical reactions, ionize some molecules or accelerate radical reactions, such as photochemical aging of varnishes[4] or the breakdown of flavoring compounds in beer to produce the 'lightstruck flavor'.[5] The light from the Sun that reaches the earth is largely composed of non-ionizing radiation, with the notable exception of some ultraviolet rays. However, most ionizing radiation is filtered out by the atmosphere (see Earth's atmosphere). Static fields do not radiate.Closing `</ref>` missing for `<ref>` tag

[2] | Source  | Wavelength  | Frequency  | Biological Effects

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UVC | Germicidal light  | 100 nm - 280 nm  | 1075 THz - 3000 THz  | Skin – Erythema, inc. pigmentation; Eye – Photokeratitis (inflammation of cornea)
UVB | Tanning booth  | 280 nm - 315 nm  | 950 THz - 1075 THz  | Eye – Photokeratitis (inflammation of cornea) Skin – Erythema, inc. pigmentation Skin cancer, Photosensitive skin reactions, Production of vitamin D
UVA | Black light, sunlight  | 315 nm - 400 nm  | 750 THz - 950 THz  | Eye – Photochemical cataract Skin – Erythema, inc. pigmentation
Visible Light | lasers, sunlight, fire, LEDs, Light Bulbs  | 400 nm - 780 nm  | 385 THz - 750 THz  | Skin photo-ageing, Skin cancer; Eye – Photochemical & thermal retinal injury
IR-A | lasers, remote controls  | 780 nm - 1.4 µm  | 215 THz - 385 THz  | Eye – Thermal retinal injury, thermal cataract; Skin burn
IR-B | lasers, long-distance telecommunications  | 1.4 µm - 3 µm  | 100 THz - 215 THz  | Eye – Corneal burn, cataract; Skin burn
IR-C | Far-infrared laser | 3 µm - 1 mm  | 300 GHz - 100 THz  | Eye – Corneal burn, cataract; Heating of body surface
Microwave | PCS phones, some mobile/cell phones, microwave ovens, cordless phones, motion detectors, radar, Wi-Fi | 1 mm - 33 cm  | 1 GHz - 300 GHz  | Heating of body surface
Radio Frequency Radiation | Mobile/Cell phones, television, FM, AM, Shortwave, CB, cordless phones  | 33 cm - 3 km  | 100 kHz - 1 GHz  | Heating with ‘penetration depth’ of 10 mm, Raised body temperature
Low frequency RF  | power lines  | > 3 km  | < 100 kHz  | Cumulation of charge on body surface Disturbance of nerve & muscle responses
Static Field[3] | strong magnets, MRI  | infinite  | 0 Hz  | Magnetic - vertigo/nausea, Electric - charge on body surface

### Ultraviolet radiation

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Ultraviolet light can cause burns to skin[6] and cataracts to the eyes.[6] Ultraviolet is classified into near, medium and far UV according to energy, where near ultraviolet is non-ionizing. Ultraviolet light produces free radicals that induce cellular damage, which can be carcinogenic. Ultraviolet light also induces melanin production from melanocyte cells to cause sun tanning of skin. Vitamin D is produced on the skin by a radical reaction initiated by UV radiation.

Plastic sunglasses (polycarbonate) generally absorb UV radiation. UV overexposure to the eyes causes snow blindness, which is a risk particularly on the sea or when there is snow on the ground.

### Visible and infrared, lasers

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Visible light causes few effects to the human body. Bright visible light irritates the eyes. Visible-light lasers have much more powerful effects and may damage the eyes even at small powers. Very strong visible light is used for cauterizing hair follicles.

### Microwave and radio frequency radiation

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* Biological effects

* Effects on the Skin
* Effects on the Eyes
* Other Hazards
* Occupational Exposure Standards

### Low frequency ELF

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* Biological effects

* Effects on the Skin
* Effects on the Eyes
* Other Hazards

* Occupational Exposure Standards

### Static fields

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* Biological effects

* Effects on the Skin
* Effects on the Eyes
* Other Hazards

cf. Electric Power Transmission.

* Occupational Exposure Standards

## See also

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* Mobile phone radiation and health
* Ionizing radiation

## References

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1. ↑ "Ionizing & Non-Ionizing Radiation".
2. ↑ 2.0 2.1 Kwan-Hoong Ng (20th – 22nd October 2003). "Non-Ionizing Radiations – Sources, Biological Effects, Emissions and Exposures" (PDF). Unknown parameter `|Journal=` ignored (`|journal=` suggested) (help); line feed character in `|title=` at position 65 (help); line feed character in `|Journal=` at position 80 (help); Check date values in: `|date=` (help)
3. ↑ 3.0 3.1 John E. Moulder. "Static Electric and Magnetic Fields and Human Health".
4. ↑ Helv. Chim. Acta vol. 83 (2000), pp. 1766. [1]
5. ↑ Photochem. Photobiol. Sci., 2004, 3, 337 - 340, DOI: 10.1039/b316210a [2]
6. ↑ 6.0 6.1 "UW EH&S Hazards of Ultraviolet Light".

de:Nicht ionisierende Strahlung he:קרינה בלתי מייננת

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