There was a book in the 1970s named THE ZAPPING OF AMERICA by Paul Brodeur which declared that RF energy could be a health hazard, especially at high power levels and at certain frequencies. Even today we hear echoes about possible microwave dangers from cell phones, cell towers, satellites, you know.
But in the Part 15 world we never suppose that microWatts are any threat, and I do not know any differently.
But I follow the subject of RF and health as closely as possible and collect publications on the subject, and have come to a very specific question that has not been well explained.
We hear that ultra-violet radiation causes cancer, particularly of the skin, and yet the ultra-violet band is just one notch above the color violet in the color spectrum, to which our eyes are sensitive (vision). So my scientific curiosity asks….
Are you trying to suggest that violet (the color) is safe, but one tweak more the ultra-violet band is not safe?
I am saying that it seems strange that visible light is (considered) absolutely safe, while just above the range of eyesight it gets dangerous.
Since when are tolerances so close?
UV
Since when are tolerances so close?
It may not be close at all since the UV band extends from just above visible violet to the X-ray region. I don’t have the information at hand but you might check the wavelengths (or frequencies) of the light involved.
As an example, the visible spectrum spans a two to one range of frequency.
Neil
Check it out
http://pw1.netcom.com/~sbyers11/RFenergy_iono.htm
Its not just tolerances, but
Its not just tolerances, but intensity that is the key. Any frequency along the entire EM spectrum can have any level of intensity.
Obviously low intensity is less harmful than higher levels.
Imagine if that cordless phone or cell phone were putting out more power than the mere 1/8th watt they do at the Ghz frequencies they operate at and what that would do to your brain cells via that nice waveguide called an ear canal.
Same with the visible spectrum and IR/UV etc etc.
Example….a grain of wheat bulb vs a 30,000 candle power spot light. Both work in the visible part of the EM spectrum, both put out the same wavelength, yet one is gonna blind you like a bat and the other make you wish there was more light!
RFB
Dangers of RF fields
I personally don’t sweat about RF. RF is radiation, but so are water ripples. It’s the word that scares people. RF is non-ionizing, and is nothing like nuclear radiation, cosmic rays, or x-rays.
RF produces heat in the body by ionic conduction. Microwave ovens demonstrate this. In the early days of radar, some people were actually cooked by RF. As long as the RF field intensity is low enough so that it doesn’t cause noticeable body temperature rise, you’re OK.
Yes, I’m aware of the non-conclusive reasearch on low-level fields, but I consider that to be just another pseudo-science scam.
I Agree!
I Agree! RF is radiation, but so are water ripples. It’s the word that scares people. RF is non-ionizing, and is nothing like fallout radiation, cosmic rays, or x-rays period, end of story.
Cosmic Radiation
When a woman “stares daggers,” is it ripples or a wave?
The radioactivity can go out of control.
BEWARE
PART 15 OPERATORS ARE RADIO-ACTIVE…
RF Hazards
The North Carolina Department of Labor ussued an RF Hazards document that lists “safe distances” from AM, FM, TV and even CB transmitters.
Many of the multi-station towers in our town are located MUCH closer to residential and commercial areas than recommended in the guidelines.
http://www.nclabor.com/osha/etta/indguide/ig11.pdf
Radiation
Ham operators are required to document that their radiated signals above a certain power level are removed a certain distance from people. Likewise, other radio services have to take measures to make people keep their distance from transmitting antennae.
The biological effect of concern for radio frequencies is tissue heating. This can be measured in vitro but it seems nobody has a good idea of what heating is hazardous and what is not.
Years ago there was a study which showed that workers in telephone exchanges had a higher rate of cancer than normal and this was attributed to exposure to electromagnetic fields in the exchanges. My question about this, which remained unanswered, was how did the researchers know it was this exposure and not exposure to the vapors from the wiring insulation.
I have yet to see any credible studies linking low level electromagnetic exposure to disease since such demographic studies do not account for cofactors properly.
I am not saying that there are not hazards but rather that we don’t know what is safe and what isn’t excepting extreme exposures.
Neil