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Nuclear Power Plants

Nuclear power plants use the heat generated from nuclear fission in a contained environment to convert water into 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.

photo of nuclear plant steam stack

Although the construction and operation of these facilities are closely monitored and regulated by the Nuclear Regulatory Commission (NRC), accidents and acts of terrorism towards these plants 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 detailed 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.

Prior to or during a nuclear power plant incident, you can find detailed information from your local television and radio stations, local emergency management agency, or local Nuclear Power Plant/Energy provider.

Take Action Before a Nuclear Power Incident

If you live within 10 miles of the power plant, you should receive materials annually from the power company or your state or local government. Obtain public emergency information materials from the power company that operates your local nuclear power plant or your local emergency services office. Learn more about nuclear plants and Seabrook Station.

Steps to Be Ready

  1. Complete the Family Emergency Plan pdf file and discuss it as a family. This is a simple way of keeping each member of the family informed on critical information: where to reconnect should you become separated, who to call, and what you will do should a nuclear power plant emergency occur.
  2. Complete the Emergency Contacts Card pdf file and place one in your Emergency Kit.
  3. Prepare an Emergency Kit. The Emergency Kit should be easily accessible should you and your family be forced to shelter in place (stay at home) for a period of time.

Be Safe During a Nuclear Power Incident

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 local television and radio stations on how to protect yourself. Follow all instructions closely, including the safest way to evacuate, if instructed to do so.

Be Safe When You Evacuate

  • If you are told to evacuate, keep car windows and vents closed; use re-circulating air.
  • Go to a designated public shelter if you have been told to evacuate or you feel it is unsafe to remain in your home.

Be Safe When You Shelter-in-Place

  • 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 your shelter-in-place location, or a below-ground location.
  • Do not use the telephone unless absolutely necessary.

Be Safe When You are at Work

  • If your workplace is out of the incident zone, stay away until local officials instruct that it is safe to return. Most radiation loses its strength fairly quickly.

Take Action After a Nuclear Power Plant Incident

If an incident happens at a nuclear power plant, local officials will provide you with information on steps to take and how to stay safe. This includes recommendations for whether or not you may need to seek medical attention.

  • If you are exposed to radiation, follow decontamination instructions from local authorities. You may be advised to take a thorough shower.
  • Change exposed 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.
  • Keep food in covered containers or in the refrigerator. Food not previously covered should be washed before being put in to containers.
  • Read the Emergency Information for Farmers, Food Processors and Distributors pdf file fact sheet.

Portable Document Format Symbol Portable Document Format (.pdf). Visit for a list of free .pdf readers for a variety of operating systems.


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