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Nuclear Power Plants

Nuclear power plants use the heat generated from nuclear fission in a contained environment to convert water to steam, which powers generators to produce electricity. Nuclear power plants operate in most states in the country and produce about 20 percent of the nation’s power. Nearly 3 million Americans live within 10 miles of an operating nuclear power plant.

Although the construction and operation of these facilities are closely monitored and regulated by the Nuclear Regulatory Commission (NRC), accidents are possible. An accident could result in dangerous levels of radiation that could affect the health and safety of the public living near the nuclear power plant.

Local and state governments, federal agencies, and the electric utilities have emergency response plans in the event of a nuclear power plant incident. The plans define two “emergency planning zones.” One zone covers an area within a 10-mile radius of the plant, where it is possible that people could be harmed by direct radiation exposure. The second zone covers a broader area, usually up to a 50-mile radius from the plant, where radioactive materials could contaminate water supplies, food crops and livestock.

The potential danger from an accident at a nuclear power plant is exposure to radiation. This exposure could come from the release of radioactive material from the plant into the environment, usually characterized by a plume (cloud-like formation) of radioactive gases and particles. The major hazards to people in the vicinity of the plume are radiation exposure to the body from the cloud and particles deposited on the ground, inhalation of radioactive materials and ingestion of radioactive materials.

Radioactive materials are composed of atoms that are unstable. An unstable atom gives off its excess energy until it becomes stable. The energy emitted is radiation. Each of us is exposed to radiation daily from natural sources, including the Sun and the Earth. Small traces of radiation are present in food and water. Radiation also is released from man-made sources such as X-ray machines, television sets and microwave ovens. Radiation has a cumulative effect. The longer a person is exposed to radiation, the greater the effect. A high exposure to radiation can cause serious illness or death.

Before a Nuclear Power Plant Emergency

First responders in hazmat gear at a hazardous scene.

The following are things you can do to protect yourself, your family and your property from the effects of a nuclear power plant emergency:

  • Build an Emergency Supply Kit, which includes items like non-perishable food, water, a battery-powered or hand-crank radio, extra flashlights and batteries. You should add plastic sheeting, duct tape and scissors to the kit in order be better prepared for a nuclear power plant incident. You may want to prepare a portable kit and keep it in your car in case you are told to evacuate. This kit should include:
    • Copies of prescription medications and medical supplies.
    • Bedding and clothing, including sleeping bags and pillows.
    • Copies of important documents: driver’s license, Social Security card, proof of residence, insurance policies, wills, deeds, birth and marriage certificates, tax records, etc.
  • Make a Family Emergency Plan. Your family may not be together when disaster strikes, so it is important to know how you will contact one another, how you will get back together and what you will do in case of an emergency.
    • Plan places where your family will meet, both within and outside of your immediate neighborhood.
    • It may be easier to make a long-distance phone call than to call across town, so an out-of-town contact may be in a better position to communicate among separated family members.
    • You may also want to inquire about emergency plans at places where your family spends time: work, daycare and school. If no plans exist, consider volunteering to help create one.
    • Knowing your community's warning systems and disaster plans, including evacuation routes.
    • Notify caregivers and babysitters about your plan.
    • Make plans for your pets
  • Obtain public emergency information materials from the power company that operates your local nuclear power plant or your local emergency services office. If you live within 10 miles of the power plant, you should receive the materials yearly from the power company or your state or local government.

Know the Terms

Familiarize yourself with these terms to help identify a nuclear power plant emergency:

Notification of Unusual Event - A small problem has occurred at the plant. No radiation leak is expected. No action on your part will be necessary.

Alert - A small problem has occurred, and small amounts of radiation could leak inside the plant. This will not affect you and no action is required.

Site Area Emergency - Area sirens may be sounded. Listen to your radio or television for safety information.

General Emergency - Radiation could leak outside the plant and off the plant site. The sirens will sound. Tune to your local radio or television station for reports. Be prepared to follow instructions promptly.

Building as Shielding

Diagram of the interior rooms and basement regions of various buildings as perfered shelter during a nuclear blast.

Building as Shelter Text Version TXT 1Kb

Numbers in this graphic stand for a 'dose reduction factor.' A dose reduction factor of 10 means that a person in that area would get 1/10th of the dose of a person in the open. A dose reduction factor of 200 means that a person in that area would receive 1/200th of the dose of a person out in the open.

For more information, read the Planning Guidance for Response to a Nuclear Detonation PDF from the Federal interagency committee led by the Executive Office of the President.

During a Nuclear Power Plant Emergency

If an accident at a nuclear power plant were to release radiation in your area, local authorities would activate warning sirens or another approved alert method. They also would instruct you through the Emergency Alert System (EAS) on local television and radio stations on how to protect yourself.

  • Follow the EAS instructions carefully.
  • Minimize your exposure by increasing the distance between you and the source of the radiation. This could be evacuation or remaining indoors to minimize exposure.
  • If you are told to evacuate, keep car windows and vents closed; use re-circulating air.
  • If you are advised to remain indoors, turn off the air conditioner, ventilation fans, furnace and other air intakes.
  • Shield yourself by placing heavy, dense material between you and the radiation source. Go to a basement or other underground area, if possible.
  • Do not use the telephone unless absolutely necessary.
  • Stay out of the incident zone. Most radiation loses its strength fairly quickly.

After a Nuclear Power Plant Emergency

The following are guidelines for the period following a nuclear power plant emergency:

  • Go to a designated public shelter if you have been told to evacuate or you feel it is unsafe to remain in your home. Text SHELTER + your ZIP code to 43362 (4FEMA) to find the nearest shelter in your area (example: shelter 12345).
  • Act quickly if you have come in to contact with or have been exposed to hazardous radiation.
  • Follow decontamination instructions from local authorities. You may be advised to take a thorough shower.
  • Change your clothes and shoes; put exposed clothing in a plastic bag; seal it and place it out of the way.
  • Seek medical treatment for unusual symptoms, such as nausea, as soon as possible.
  • Listen to local radio or television stations for the latest emergency information.
  • Help a neighbor who may require special assistance - infants, elderly people and people with access and functional needs may require additional assistance. People who care for them or who have large families may need additional assistance in emergency situations.
  • Return home only when authorities say it is safe.
  • Keep food in covered containers or in the refrigerator. Food not previously covered should be washed before being put in to containers. 


Related Websites

Find additional information on how to plan and prepare for a nuclear power plant emergency and learn about available resources by visiting the following websites:

Listen to Local Officials

Learn about the emergency plans that have been established in your area by your state and local government. In any emergency, always listen to the instructions given by local emergency management officials.