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Published byChristal O’Connor’ Modified over 9 years ago
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NONIONIZING RADIATION ….. a discussion of the health hazards associated with exposures to non- ionizing radiation
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The Electromagnetic Spectrum u A name scientists give to a number of different types of radiation when they talk about them as a group u Energy is proportional to frequency and is inversely proportional to wavelength u Inherent energy defines the transition between ionizing and non-ionizing radiations
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Electromagnetic Spectrum u Electromagnetic Spectrum Video Clip Electromagnetic Spectrum Video Clip Source: http://imagine.gsfc.nasa.gov/docs/science/know_l2/emspectrum.html
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THE NON-IONIZING RADIATIONS u RF, (RADIO FREQUENCY) u MICROWAVES u INFRARED u VISIBLE (LASER) u ULTRAVIOLET u AND BEYOND
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ULTRAVIOLET u Types: UV-A, UV-B, and UV-C u SOURCES: sun, mercury lamps, welding, lasers, pest control (fly lamps), fluorescent lighting u Target Organs: skin, eyes, immune system
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Biological Effect [UV] u Aging of the skin u Reddening of the skin (erythema) u Skin cancer upon prolonged exposures u Corneal injury u Photosensitization (with some chemicals) u Benefits – Induces production of Vitamin D in skin
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LASERS u Light Amplification by Stimulated Emission of radiation (LASER) u COHERENT u MONOCHROMATIC u DIRECTIONAL
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Biological Effects [LASERS] u Primarily to the eye –retinal injury is most significant u Secondarily to the skin
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INFRARED u SOURCES: most are thermal sources (plasma torches, halogen lamps) u Target Organs: skin and eyes
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Biological Effects [Infrared] u Primarily thermal in nature u Skin: heats/burn surface of the skin and tissues immediately below u Eyes: Can damage retina and cornea, cause cataracts infrared: u Easiest to avoid: you can see it & feel it
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MICROWAVE APPLICATIONS u Sources: –Radar –Communications. –TV –Heating and drying –Air traffic control
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Biological Effects [Microwaves] u Primarily thermal effects u Capable of forming cataracts u CNS, biochemical changes? u Secondary problems (pace-makers, etc.)
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RADIO FREQUENCY u What we said about microwaves applies for RF waves also, only to a lesser degree. u This area, and the extra low frequency (ELF) energies are getting a lot of attention right now!
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