Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne 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



Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory