Questions And Answers About EMF

For general information about EMF – what they are, what causes them, whether they can be blocked or mitigated, etc. – please consult our answers to the following frequently asked questions.

What are electric and magnetic fields?

Commonly called EMF, electric and magnetic fields are invisible lines of force present in the natural environment and wherever electricity flows.

Sources of EMF include electric power lines, electrical wiring in homes and businesses, home appliances, office equipment, electric tools and hospital diagnostic equipment.

Electric fields are produced by voltage or electric charge. These types of fields are measured in volts per meter (V/m). The higher the voltage, the greater the electric field.

A lamp cord that is plugged in produces an electric field even if the lamp is not on.

Magnetic fields are created by the current or flow of electricity in a wire. As current increases, the field strength increases. When an appliance is turned on, the magnetic field is produced. The magnetic field is not present when the appliance is turned off.

Magnetic fields are measured in units called gauss or Tesla and typically are reported in milligauss or mircroTesla. Note: 1 guass = 1,000 milligauss (mG); 1mG= 0.1 mircroTesla.

Appliances produce EMF

Lamp off and on

How does nature produce EMF?

Electric and magnetic fields are present in and around the earth, which has a magnetic field strong enough to make a compass needle point north. This field averages approximately 500 mG at the earth's surface and is relatively static.

Unlike alternating current (AC) magnetic fields associated with power lines, static or direct current (DC) fields do not cause electrical charges to flow in stationary objects. Thunderstorm activity in the atmosphere is a source of naturally-occurring EMF.

How does power frequency EMF (EMF associated with power lines and household appliances) compare with other sources of electromagnetic energy?

The electromagnetic spectrum covers a wide range of frequencies. These frequencies are expressed in hertz (Hz) or cycles per second.

Electrical current associated with power lines and household appliances is characterized by extremely low frequencies -- 60 Hz AC, meaning the direction of current alternates at a rate of 60 times per second.

Energy associated with x-rays, for example, is at the higher end of the electromagnetic spectrum.

Scientists generally agree that 60 Hz fields are not powerful enough to damage the body's genetic material or to directly cause cancer.

Electromagnetic spectrum (frequency in Hz)

Electromagnetic spectrum (frequency in Hz)

This chart illustrates some common sources of electromagnetic energy.

Is it possible to block EMF?

Electric fields are blocked by trees, shrubs, building materials and other objects. Magnetic fields, on the other hand, are not easily blocked and can pass through most objects.

The strength of both electric and magnetic fields declines rapidly with distance from the source.

Typical magnetic field ranges (in mG)

Distance from appliance 6 " 1 ' 2 ' 4 '
Microwave ovens 100 - 300 1 - 200 1 - 30 * - 20
Electric ranges 20 - 200 * - 30 * - 9 * - 6
Refrigerators 4 - 100 * - 20 * - 10 * - 10
Clothes washers 4 - 100 1-30 * - 6 *
Clothes dryers 2 - 10 * - 3 * *
Fluorescent lamps 20 - 100 * - 30 * - 8 * - 4
Hair dryers 1 - 700 * - 70 * - 10 * - 1
Color televisions   * - 20 * - 8 * - 4
Analog clocks   1 - 30 * - 5 * - 3
Vacuum cleaners 100 - 700 20 - 200 4 - 50 * - 10
Copy machines 4 - 200 2 - 40 1 - 13 * - 4
Video display terminals 7 - 20 2 - 6 1 - 3 *
Electric blankets 1 - 40 (at 2")      
Note: the asterisk (*) indicates same as background fields.
Source: EMF In Your Environment, EPA 1992
How does EMF exposure vary throughout the day?

A person is routinely exposed to EMF from a large number of sources throughout the day. Electric and magnetic field exposure depends to a large degree on what a person is doing.

The chart illustrates how a person's exposure to EMF may fluctuate during a 24-hour period. It is important to note that no level of electric or magnetic field has been determined to be hazardous.

Example of 24-hour magnetic field exposure

24-hour magnetic field exposure

While asleep, this person's magnetic field exposure was less than 1 mG. During the day, exposure varied to a peak of about 20 mG. Average magnetic field exposure during this 24-hour period was 0.5 mG.

What type of EMF research is being done?

Electric and magnetic field research currently is focused on three main areas:

  1. Laboratory or basic science studies which look at effects of EMF on cells and tissue samples of humans and animals.
  2. Epidemiological studies which use statistics to determine whether an association exists between a disease and an environmental factor such as EMF exposure.
  3. Exposure assessment studies which look at the sources and amount of EMF exposure.
What has research shown?

Scientific studies over the past several decades have explored the possibility of health effects from EMF exposure. While some of the studies have indicated some statistical associations between EMF and certain health effects, the majority of research has found no such association. Significantly, laboratory research has not shown any causal relationship between EMF exposure and cancer, or any other adverse heath effects.

AEP was among sponsors of the U.S. Department of Energy $45 million EMF Research and Public Information Dissemination (RAPID) Program which concluded that “scientific evidence suggesting that EMF exposures pose any health risk is weak.”

What is AEP doing?

AEP has been involved in the EMF issue by following worldwide scientific developments, participating in EMF research, sponsoring studies and communicating with customers and employees on the issue.

AEP was a sponsor of the U.S. Department of Energy's $45 million EMF Research and Public Information Dissemination (RAPID) Program which concluded that “scientific evidence suggesting that EMF exposures pose any health risk is weak.”

AEP also is a member of the Electric Power Research Institute, which sponsors and coordinates EMF laboratory, epidemiological and exposure studies.

In addition to monitoring and sponsoring research, AEP shares the results of these programs with customers and employees.

AEP's overall responsibility is to continue providing safe and reliable electric service and a safe working environment for employees.

Can EMF measurements be taken in my home?

Upon request, an AEP representative will conduct EMF measurements at your home. However, the representative will not be able to interpret whether the field levels are safe or hazardous because no level of exposure has been determined to be unsafe.

More From APCO

Take Charge

Save Money & Energy - Now & Later

Pick Your State

×
Sign Up Now Pay Online for Free with Paperless Billing

Pay Online for Free with Paperless Billing

Use Online Form Report Outages On Your Mobile Phone

Report Outages On Your Mobile Phone

How We Restore Power Learn more

How We Restore Power

Learn the steps APCO takes to quickly and safely get the power back on

Visit AEP.com
Use of this site constitutes acceptance of the AEP Terms and Conditions. View our Privacy Policy. © 1996-2015 American Electric Power. All Rights Reserved.

Privacy Policy for Appalachian Power, a unit of American Electric Power (AEP)

Scope

This Privacy Policy applies only to AppalachianPower.com

Other Websites in the AEP family of sites may be governed by their own privacy policies, appropriate to the uses and needs of each site. Throughout this site, we may provide links to resources and sites that are not part of AppalachianPower.com. This Privacy Policy does not apply to those resources and sites.

Consent

By using this site, you consent to the terms of this Privacy Policy. Whenever you submit information via this site, you agree to the collection, use, and disclosure of that information in accordance with this Privacy Policy.

Information Collected

  1. Passively collected information

    During your use of this site, we may collect anonymous information about your visit here through the use of server logs, cookies, scripts and other Web traffic tracking systems. This information is aggregated and used to improve our site through analysis of user activities on the site. This information is never combined with any of the personally identifiable information you may provide in your use of the features of this site.
  2. Personally identifiable information

    On certain pages of this site, you may be asked to provide information about yourself or your account with us, either to identify yourself to us or to request a service from us. In each case, we will inform you what information is provided at your option and what information is required to complete the transaction or activity you are engaged in. If you are unwilling to provide this required information, you will be unable to complete the requested transaction.

Use and disclosure of information

The information you provide to us will be used to respond to requests you may make for services. Some or all of this information may be added to your permanent account record and may be used for research purposes.

In addition, we may use elements of this information in the following situations:

  1. We may transfer the information to AEP’s affiliates and subsidiaries, unless such transfer is prohibited by law;
  2. We may transfer the information as part of a merger, consolidation, acquisition, divestiture or other corporate restructuring (including bankruptcy);
  3. We may make the information available to third parties who are providing the product, service or information that you have requested (but not your password);
  4. We may make such information available to third parties who are providing services to AEP (for example, providing the information to third parties performing computer-related services for AEP);
  5. We may use the information to communicate with you about products and services that may be of interest to you.
  6. We may disclose the information if we form a good-faith belief that disclosure of such information is necessary to investigate, prevent, or take action regarding any illegal activities or regarding interference with the operation of our site or violation of its terms of use; or
  7. We may disclose the information if we believe that disclosure is required by law or regulation or in response to a subpoena or other order of a court or other governmental agency.

Also, AEP reserves the right to share any aggregated information (i.e., non-personally identifiable information) with any third parties for any reason, unless prohibited by law.

We will not sell, rent or otherwise disclose the information we gather about you or your account to any third party, except as outlined in this Privacy Policy.

Security

AEP takes reasonable steps to protect your personally identifiable information as it is transferred to us, through the use of Web technologies such as the Secure Sockets Layer and others. However, no Internet transmission of information is ever completely secure or error-free. In particular, e-mail sent to or from AEP may not be secure.

How to Reach Us

If you would like to update your personally identifiable information or if you have questions about this privacy policy, please contact us.

Changes to This Policy

AEP reserves the right to change this Privacy Policy at any time. If this Privacy Policy changes, the revised policy will be posted to this site. Please review this Privacy Policy before you provide any personally identifiable information through this site. Use of our web site after the posting of a revised privacy policy constitutes your consent to the revised policy.

This policy was last revised on September 12, 2011.

Close ×

Sign Up For Alerts

Subscribing to APCO alerts gives you instant notification for:

  • Billing & Payments - avoid late payments and disconnection
  • Outage Updates - find out if there's an outage at your address and when power will be back on

Loading video...

×
  • Log In
  • Register
  • 1-800-956-4237