Penetration
Communication microwave frequencies penetrate conductive materials, including semi-solid substances like meat and living tissue, to a distance defined by the skin effect. The penetration essentially stops where all the penetrating microwave energy has been converted to heat in the tissue. For this reason, it may be dangerous to stand close to high-power microwave antennas such as those used for broadcasting over long distances (tens of miles); a person near such antennas may experience severe penetrating burns, which (in the worst cases) may include serious burn injury to internal organs.
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