Subject: (Curry) Re EMR - How close is too close? (fwd)
Date: Mon, 5 Oct 1998 040419 -0500 (CDT)
From: "Roy L. Beavers" <rbeavers@llion.org>
To: emfguru <rbeavers@llion.org>
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---------- Forwarded message ----------
Date: Mon, 05 Oct 1998 00:54:56 -0600
From: "Bill P. Curry"
To: "Roy L. Beavers"
Subject: Re: EMR - How close is too close? (fwd)
Roy and Scott,
I am assisting (gratis) some homeowners who are in a similar quandary as
yours - except that they already own their property. I have given one of them
substantial sets of data: article reprints from scientific journals, notices
published on the EMF list about legal arguments which have been used against
cell phone companies, and Alasdair Phillips excellent summary of reported
works on cell phones and health hazards. I will join them at the hearing at
which their case is being processed this evening Oct. 10.
In regard to your question, note that Dr. John Goldsmith (in his article
entitled "Epidemiological Evidence Relevant to Radar (Microwave) Effects")
says "...exposures as low as 2 microwatt/square centimeter may have long term
health effects."
Insofar as your qualms about living too close to a TV station are concerned,
I suspect that as close as you say, most of the radiation is above your head -
i.e., it probably does not reach the ground level at that close a horizontal
range (except for slight spillover and leakage from the main beam due to
atmospheric scattering and scattering from suspended particles in the air).
The spillover probably contributes enough signal for you to receive it on your
TV set, but I doubt that it provides a harmful ambiance. Most TV transmitting
antennas are quite high, and the radiation is horizontally polarized, so it
should travel mostly in straight lines from the antenna itself. In addition, I
think the frequencies usually involved in TV broadcasting are probably too low
to be as potentially dangerous as cell phone radiation - unless you are in a
high radiation density area. Nevertheless, it would probably be a good idea
to have someone measure the microwave power density at your proposed location
before you buy the house. The measurement should be in the frequency range of
the TV station, as well as the cell phone frequencies. (around 900 Mhz for
analog cell phones and near 2,000 Mhz for PCS cell phones).
Some biolectromagnetics experts (Ross Adey, I think) suspect that the
potential danger of microwave radiation from PCS phones is because the
radiation is pulsed. I don't know whether the radiation from analog phones is
pulsed or not. The significance of pulsing to me lies in the fact that
(biological) cellular responses have been observed for EMF with a range of
frequencies of sinusoidal magnetic fields from 0 - 500 Hz. Different enzymes
respond to different frequencies. The pulse repetition rate of PCS phones is
around 200 Hz. A rectangular pulse will consist of sine waves with many
different frequencies, but the primary energy concentration will be near the
pulse repetition frequency. Also the studies of EMF effects on mice by
Rapacholi used pulsed EMF to simulate digital phone radiation.
At the distances you mentioned to both types of microwave sources, I don't
think you can use a simple spherically expanding radiation law to estimate how
the radiation power density will fall off with distance from the sources you
mentioned. This is because TV antennas and Cell phone antennas are
directional, and hence their emitted radiation will off with distance more
slowly than an inverse square law until you are far enough away from all the
sources for them to appear as nearly point sources. It would be fair, it
seems to me, for you ask both the TV station and the cell phone company to
provide maps of the expected radiation density contours in your area.
All in all, I think your qualms are justified, and I recommend getting some
disinterested RF consultant with proper measuring equipment to survey your
proposed purchase before you buy.
--
----
Bill P. Curry, Ph.D. |Physics is fun.
EMSciTek Consulting Co. |Trying to make a living!
22W101 McCarron Road, |Phone: (630) 858-9377
Glen Ellyn, IL 60137 |Fax: same, but require prior notice
Home page: http://www.EMSciTek.com
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Reprinted with permission of Roy Beavers, http://www.feb.se/EMF-L/EMF-L.html