الفهرس 
Chapter 1Only 14 pages are availabe for public view
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Abstract
Until recently, the natural electromagnetic background was relatively constant, but the situation changed markedly and precipitously with the development of modern communications and electrical power systems. The environment is now heavily laden with man-made electromagnetic fields (EMFs) from radio; TV, microwave relay, and many similar sources. Static magnetic fields (SMFs) are time-independent fields of constant strength.Extremely Low Frequency electromagnetic Fields (ELF-EMF)are electromagnetic oscillating fields defined ashaving frequencies below 300 Hz. ELF-EMFs are veryimportant from a public health standpoint because of thewidespread use of electrical power at 50 or 60 Hz in mostcountries. Electric and magnetic fields exist aroundelectrical equipment and wiring throughout industry.Workers who maintain transmission and distribution linesmay be exposed to very high electric and magnetic fields [1.