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What is radiofrequency /microwave (RF/MW) radiation?

(Excerpts and illustrations from Electromagnetic Fields: A Consumer’s Guide to the Issues and How to Protect Ourselves by B. Blake Levitt, Harcourt Brace, 1995. Used by permission of author.)

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Radiofrequency radiation falls between about 3 kilohertz and 300 gigahertz on the electromagnetic spectrum. This is a broad area on the electromagnetic spectrum which includes many frequencies and wavelengths.

Microwave (MW) radiation runs from a few megahertz up to around 100 gigahertz, which is used for military communications.

All radio waves (RF/MW) radiate into space at the speed of light (186,000 miles per second), and each wave is associated with a wavelength and a frequency. Wavelength refers to the distance that the wave travels through space in a single cycle between one peak or valley of the radio wave and the next. Frequency indicates the number of waves in one second.

Since the radiofrequency range is such a broad one, the wavelengths vary considerably. There are long waves, medium waves, and short waves, and further categories called extremely low frequency (ELF), very low frequency RF/MW radiation(VLF), low frequency (LF), medium frequency (MF), high frequency (HF), very high frequency (VHF), ultra high frequency (UHF), super high frequency (SHF), and extremely high frequency (EHF). Microwaves occupy the ultra, super, and extremely high frequency bands; radar is a part of the microwave frequencies. Currently, mobile telecommunications consumer devices such as cell phones generally operate between 800 and 2400 megahertz. However, future consumer products are being developed that operate at much higher frequencies.

RF/MW radiation is transmitted by all types of telecommunications antennas. The environment around antenna sites (called “near” fields) can be electromagnetically complex, to say the least. Radio waves couple with each other as well as with other frequencies, and in some circumstances (like the presence of metallic objects) can create what are called standing waves or “hot spots”, meaning that they do not radiate into space, but remain within a set area at high intensities. Couplings can add to or subtract from each other, and complex fields of high power intensities can and regularly so interfere with nearby radios and TVs – and undoubtedly with a person’s innate biological fields as well. There is some indication that certain FM frequencies may create standing waves in the brain that the body cannot dissipate. It is also one of the concerns about mobile phones that use microwave frequencies.

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