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Electric and Magnetic Fields

Electric and magnetic fields are generated by all power sources, including conductors, wiring, tools, and appliances. The fields increase with the magnitude of the power source, but dramatically decrease with distance from the source conductor or wiring.

Electric fields and magnetic fields are independent of each other.

  • Electric fields result from the energization of the wiring.
  • Magnetic fields result from the flow of power (current) as it serves the load being applied.

Electric fields are reduced by distance, by mutual cancellation (placing the wires as close together as possible without creating an arc between them) or by placing objects or insulation between the wire and the exposure location. Magnetic fields are reduced by distance, by mutual cancellation, or by specific types of shields. However, they are not reduced by most objects between them and the source wires.

Health effects

The incidence of cancer has not increased with the increased use of electricity in the United States or any other country that measures incidence rates. Scientists and doctors have found no testable hypothesis that demonstrates a possible mechanism by which power fields can cause adverse health effects, cancer, or any other disease or debilitating condition.

The effects of fields from power lines have been the object of research since the late 1950s. Over 26,000 research reports have been generated in that time, and none report adverse health cause and effect. High exposures in controlled laboratory tests have not created any adverse cause-and-effect relationship.

A 1979 study in Denver, Colorado, reported on preliminary research of possible environmental factors associated with childhood cancer. Since then, at least a dozen similar studies have been completed in an effort to determine the relationship. More than half of the studies reported no association. Those that did report a possible association have not been reproducible in later studies that were larger and better controlled.

Using the raw data on fields and exposures collected in the dozen studies, the International Agency for Research on Cancer concluded that there may be a possible association between a single, rare form of childhood cancer and magnetic fields. If the possibility does exist, it is a very low probability and a mechanism for causation is not known.

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Examples of Common Sources of Magnetic Fields

 

Source Median Highest
Hair dryers

300 mG* at 6 inches
1 at 1 foot

700 mG at 6 inches
70 at 1 foot
Electric razors 100 mG at 6 inches
20 at 1 foot
600 mG at 6 inches
100 at 1 foot
Blenders 70 mG at 6 inches
10 at 1 foot
100 mG at 6 inches
20 at 1 foot
Can openers 600 mG at 6 inches
150 at 1 foot
1500 mG at 6 inches
300 at 1 foot
Coffee makers 7 mG at 6 inches
immeasurable at 1 foot
10 mG at 6 inches
1 at 1 foot
Dishwashers 20 mG at 6 inches
10 at 1 foot
100 mG at 6 inches
30 at 1 foot *milligauss
Microwave ovens 80 mG at 6 inches
10 at 1 foot
100 mG at 6 inches
20 at 1 foot
Mixers 100 mG at 6 inches
10 at 1 foot
600 mG at 6 inches
100 at 1 foot
Electric ranges 30 mG at 6 inches, 8 at 1 foot 200 mG at 6 inches, 30 at 1 foot
Refrigerators 2 mG at 6 inches
2 at 1 foot
40 mG at 6 inches
20 at 1 foot
Vacuum cleaners 300 mG at 6 inches
60 at 1 foot
700 mG at 6 inches
200 at 1 foot
Analog clocks 15 mG at 1 foot 30 mG at 1 foot
Baby monitors 6 mG at 6 inches
1 at 1 foot
15 mG at 6 inches
2 at 1 foot
Battery chargers 30 mG at 6 inches
3 at 1 foot
50 mG at 6 inches
4 at 1 foot
Hand drills 150 mG at 6 inches
30 at 1 foot
200 mG at 6 inches
40 at 1 foot
Power saws 200 mG at 6 inches
40 at 1 foot
1,000 mG at 6 inches
300 at 1 foot
Copy machines 90 mG at 6 inches
20 at 1 foot
200 mG at 6 inches
40 at 1 foot
Fax machines 6 mG at 6 inches 9 mG at 6 inches
2 at 1 foot
Fluorescent lights 40 mG at 6 inches
6 at 1 foot
100 mG at 6 inches
30 at 1 foot
Pencil sharpeners 200 mG at 6 inches
70 at 1 foot
300 mG at 6 inches
90 at 1 foot
Computers with color monitors 14 mG at 6 inches
5 at 1 foot
20 mG at 6 inches
6 at 1 foot

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Additional sources of information

 

Reviews of EMF research:

Online sources of information:

 

 

 

 

 

 

 

 

           
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