In article <CJFF8p.56v@spk.hp.com>, depaul@spk.hp.com (Marc DePaul) writes:
|> Hello.
|>
|> If this has been discussed before, I'm sorry, I haven't seen it.
|>
|>
|> The ARRL handbook mentions that we should keep the face of an amp
|> at least 24 " from our body, etc. Rigs, power supplies, antenna tuners,
|> and antennas are also hazardous to our health when set too close to our
|> body.
|>
|> So now my amp is approx 4 feet from me, and my open wire antenna tuner
|> is now 7 feet from me. I'm also about 2 feet from the face of the rig.
|> I'm hoping that will do the trick to be immune from cancer...
|>
|> They mention that attic antennas are a no-no, and it appears mobiling
|> douses your body with an rf field big time.
|>
|> There is statistically significant cancer rates above the non-electronic
|> population.
|>
|>
|> What I want to hear out there is anyone who has done, or is knowledgeable
|> of work done in this field...Let us know.
|>
|>
|> Regards,
|>
|> Marc
If you have studied RF-EM radiation and its biological effects, you know that there are four factors that need to be considered (not withstanding the actual research methods - which is an entirely different subject) which are intensity, proximity, frequency, and length of exposure.
True that the hand-helds are 1/2 w, but the EM fields are much more intense
(literally right against your skull). The police handhelds typically are the 'walkie-talkie' style and they have also learned to point the antenna away from the body (head in particular), thereby greatly reducing the field intensity. The EM field intensity has an inverse square relationship with proximity.
We have through research seen various effects on the body at various frequencies. Example, your microwave is set at a particular frequency that
will excite water molecules, thereby creating heat. At 27 Mhz (CB frequencies), the EM field has an affect on the sleep center of the brain. Exteremly low audio frequencies can, well let's just say can have an GI reaction.
The most critical factors, IMHO, is the length of exposure. The individual from
Motorola on Eye-to-eye that claimed brain cancer from cell-phone use was also
testing prototype antennas. I strongly suspect he spent hours per day on
a cell-phone close to his head. Length of exposure is directly in the users
control.
There was an intresting related story several months ago about how some police
officers were developing prostrait (sp ?) cancer. They also linked it to
a practice of removing the radar gun from its mounting on the exterior of the
vechicle and keeping it between their legs (as to not alert motorists). They
were using the equipment in direct contrdiction to the manufacturer's recommendations.
Measuring biological effects of RF-EM radiation is itself somewhat contriversal.
The only agreed upon measurement (that I am aware of) is the change in temperature in tissue. It was shown in a seminar that I attended on the subject, that long term cell exposure will raise the brain tissue.
On the subject on research methods (which I know little about), here is a
humorous happening tht illustraits the complexity of the problem. A group of
researchers were studying the effects of RF on lab rats. They noticed when a
particlar frequency was used, the rats would run wildly until they eventually
sat in a water bowl. They concluded that this frequency had a effect on the rat's brain. Later in discussing their result, a radio engineer asked what the
frequency was, and after doing some calculation, found the rat's tail was a
perfect antenna for that frequency, hense, the tail was getting HOT !
There is much more that we don't know about RF-EM effects on biological systems
than we do know. In the meantime, the best thing to do is not panic, not ignore, but use good ol' common sense.
