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Radiation and Health
Name: Lucia R.
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 2001-2002
Question:
I live close to a radio antenna. Does it have radiation.
If so, how much and what is the safest distance?
Replies:
Hi, Lucia !!
There is no problem living near a radio antenna.
Radio waves are no more than electromagnetic
waves that fulfill our universe. They are like waves
on a lake surface and the major part is invisible
to us. The small part visible is what you can see
with your eyes. The radio waves have a length
from 30 cm to 150 m and you live surrounded by
them. When you switch on a blender
in the kitchen, you produce radio waves and
your TV will show an interference ( bzzz !!!! )
on the screen. Radio waves are NOT dangerous.
Dangerous are indeed waves that can produce
ions, like radioactivity. They destroy human
cells. In 1888, a German called Heinrich Hertz
could produce the first radio waves. But it
was Lee Forest, in 1903, an American engineer
that discovered the practical use for the radio
waves.
Alcir Grohmann
Hello,
If the antenna is for reception - e.g., the antenna on your radio - no
radiation is emitted from it. It receives radio frequency (RF) radiation that
is present in space.
If the antenna is for transmission - e.g., the ones used by radio or TV
stations to broadcast, then it emits radiation. How much radiation you
receive is dependent on the emitted radiation power, its frequency, and your
diastase from the antenna, squared. This means that if you double your
distance from it, radiation level drops four times.
There is risk associated with exposure to RF radiation. RF is absorbed in the
body. Allowable radiation absorption levels (far below known damage
thresholds) have been established by the Federal Communications Commission
(FCC). In one set of regulations, whole or partial body radiation absorption
is limited to 0.04 W/kg. As an example, the closest "safe" distance from a
10 kW radio station for a 50 kg (90 Lb) person with a body surface of 0.6 m^2
is:
{[10000 W]/[4(pi}R^2]} x 0.6 m^2 < [0.04 W/kg][50kg]
from which the distance R is found to be about 15 m (50 ft).
For further information, please check bulletin 56 at following web site.
http://www.fcc.gov/oet/info/documents/bulletins/#56
Good luck,
AK
--
Ali Khounsary, Ph.D.
Lucia,
First, understand that very little radiation is dangerous. Visible light is
radiation. The signals received by your television and stereo are
radiation. Some of the heat you feel from a fire is radiation. The
frequency of the radiation is just as important as the amount. High
frequency radiation (ultraviolet, microwave, gamma) are what you need to
worry about. Radio waves do not even "see" your body. They pass through as
if it were not there. Likewise, your body does not notice the radio waves.
The greatest danger of a radio antenna is electricity. Touching it might
cause your body to start acting as part of the antenna. That would not be
good. Another problem of a nearby radio antenna is interference with TV and
radio signals from other antennas in the world. The sun is much more
dangerous than the signal from a radio antenna.
Dr. Ken Mellendorf
Illinois Central College
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