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Radiation Emergencies and Preparedness

Radiation Facts

If a radiation emergency occurs, take the following actions to protect yourself, your loved ones and your pets.

Get Inside, because walls and dirt can protect you from radiation.

Stay Inside for up to 24 hours, unless the authorities, like a police officer or firefighter have told you it is safe to leave.

Stay Tuned to local radio and television stations and official social media accounts for more information and instructions.

Radiation emergencies can be intentional acts designed to hurt others, like a terrorist attack, or they can be accidents that occur when using radioactive material. If a radiation emergency ever happens, it is important to remember to get inside a sturdy building, and into the basement or the innermost room, stay there for at least 24 hours, and stay tuned to the news, official social media accounts, or the radio.

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About Radiation Emergencies and Preparedness

Radiation emergencies can be intentional acts designed to hurt others, like a terrorist attack, or they can be accidents that occur when using radioactive material. A nuclear power plant accident, nuclear explosion or a dirty bomb are examples of radiation emergencies.

Unintentional acts, or radiation accidents, can include:

  • Nuclear Power Plant Accident – An accident at a nuclear power plant could release radioactive material into the air or water around a nuclear power plant. The 1979 accident at Three Mile Island Nuclear Power Plant in Pennsylvania is an example of a nuclear power plant accident. Read more about the U.S. Nuclear Regulatory Commission’s (NRC’s) Three Mile Island incident fact sheet.
  • Transportation Accident – Radioactive materials are transported by sea, rail, roadway and air. Traffic accidents or other incidents could cause shipments to release radioactive materials. Very strict rules apply to transporting radioactive material during shipment. Because of this, radiation emergencies during the transportation of radioactive materials are extremely rare. Learn more about Transporting Radioactive Materials.

Intentional acts that use radioactive materials include:

  • Nuclear Weapons – A nuclear weapon is a device that uses a nuclear reaction to create an explosion. This explosion is much more powerful than that of conventional explosives (like TNT). When a nuclear weapon explodes, it gives off four types of energy: a blast wave, intense light, heat, and radiation. Nuclear weapons can be in the form of bombs or missiles. Some nuclear explosions produce fallout, a collection of radioactive material that can deposit on the ground, structures and buildings, or be carried by the wind. For example, during World War II, the United States used nuclear weapons against two Japanese cities, Hiroshima and Nagasaki. Since 1945, no nuclear weapons have been used against another country.
  • Radiological Dispersal Device (RDD) – An RDD, also known as a dirty bomb, uses a combination of explosives and radioactive materials to produce an explosion. Typically, the aim of this explosion is to spread radioactive materials into the surrounding area. Fortunately, no one has ever used a dirty bomb in an act of terrorism. Learn more about RDDs and dirty bombs at the U.S. Nuclear Regulatory Commission’s fact sheet.

For more information about types of radiation emergencies, see the Centers for Disease Control webpage on types of emergencies.

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What You Can Do

During a radiation emergency, the main goal is to keep your exposure to radiation as low as possible. It’s important to listen for guidance on how to respond to keep you, your family and your pets safe.

This image shows a person entering a sturdy building as quickly as possible during a radiological emergency.Get Inside

Get Inside – During a radiation emergency, you may be asked to get inside a building and take shelter for a period of time. The walls of buildings can block much of the harmful radiation. More walls between you and the outside provides more protection, so good places to shelter include basements or rooms with no windows in the middle of your home. Because radioactive materials become weaker over time, staying inside for at least 24 hours can protect you and your family until public health or law enforcement officials tell you it is safe to leave the area.

This image shows two people and a dog staying inside the middle of a sturdy building during a radiological emergency.Stay Inside.

Stay Inside – Stay inside until you are told to leave by the police, fire department or government officials. While you are inside, you can take simple steps to remove any radioactive material that might be on your body. Take off your outer layer of clothing (like jackets and pants), gently wash your skin with water and put on clean clothes to remove radioactive material. Try to drink only unopened canned or bottled drinks and eat only packaged foods. Make sure to wash the packages before you consume food or drinks from them, in case radioactive material has settled on your food and drink packages.

This image shows a person sitting in a sturdy building, listening to a radio to hear more information or instruction about what to do during a radiological emergency.Stay Tuned.

Stay Tuned – Once you get inside, it will be important to stay tuned for updated instructions from emergency response officials. As officials learn more about the emergency, they will communicate the latest information and safety instructions to the public. Television, radio, and social media are some examples of ways that you may receive important safety information.

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