3. Dielectric properties of media
Materials are generally classified as either magnetic or non-magnetic. Unlike non-magnetic materials, magnetic materials have magnetic dipoles that are strongly affected by applied fields.
The materials encountered in radiofrequency dosimetry, human tissue but also textiles such as cotton, silk, leather, etc., are non-magnetic materials and their magnetic permeability is that of a vacuum (µ = µ 0 = 4.10 -7 H/m). This makes permittivity the key parameter for determining the distribution of the electromagnetic field in the body and therefore the power dissipated there.
Anisotropy is negligible in textiles and human tissue (for frequencies above MHz), which simplifies the general form of the electrical permittivity tensor into a complex scalar quantity:...
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Dielectric properties of media
Specific absorption rate measurement
Bibliography
Websites
Radio frequency portal – health – environment
http://www.radiofrequences.gouv.fr/
(page consulted on July 3, 2015)
Standards and norms
Guide for setting exposure limits to electric, magnetic and electromagnetic fields – Alternating fields (time-varying frequency, up to 300 GHz, ICNIRP 1998.
- IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz. - IEEE Standard C95.1-2005 -
- Human exposure to radiofrequency fields produced by wireless communication devices...
Regulations
Directive 2013/35/EU of the European Parliament and of the Council of June 26, 2013 on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (electromagnetic fields).
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