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Homeland Security

Radiological Attack: What to Do

What are some common radioactive materials used in our society?

Gamma Emitters
Cobalt-60 (Co-60)—cancer therapy, industrial radiography, industrial gauges, food irradiation.
Cesium-137 (Cs-137)—same uses as Cobalt-60 plus well logging.
Iridium-192 (Ir-192)—industrial radiography and medical implants for cancer therapy.

Beta Emitter
Strontium-90 (Sr-90)—radioisotope thermoelectric generators (RTGs), which are used to make electricity in remote areas.

Alpha Emitters
Plutonium-238 (Pu-238)—research and well logging and in RTGs for space missions.
Americium-241 (Am-241)—industrial gauges and well logging.

Time, Distance and Shielding

Following any radiological explosion, people should:

  • Minimize the time they are exposed to the radiation materials from the dirty bomb.
  • Maximize their distance from the source; walking even a short distance from the scene could provide significant protection since dose rate drops dramatically with distance from the source.
  • Shield themselves from external exposure and inhalation of radioactive material.

Practical Steps

If people are near the site of a dirty bomb or release of radioactive material, they should:

  • Stay away from any obvious plume or dust cloud.
  • Cover their mouth and nose with a tissue, filter, or damp cloth to avoid inhaling or ingesting the radioactive material.
  • Walk inside a building with closed doors and windows as quickly as can be done in an orderly manner and listen for information from emergency responders and authorities.
  • Remove contaminated clothes as soon as possible; place them in a sealed container such as a plastic bag. The clothing could be used later to estimate a person's exposure.
  • Gently wash skin to remove possible contamination; people should make sure that no radioactive material enters the mouth or is transferred to areas of the face where it could be easily moved to the mouth and ingested. For example don't eat, drink, or smoke.

Questions such as when it's safe to leave a building or return home, what is safe to eat and drink and when, and how children will be cared for if they are separated from their parents would be answered by authorities who would have to make decisions on a case-by-case basis depending on the many variables of the situation.

Decisions Regarding Evacuation

Evacuation as a plume is passing could result in greater exposures than staying indoors, also known as sheltering in place. The best course of action will be provided by emergency officials who may use computations from models of plume travel and potential radiation health effects.

Reducing Contamination

Contaminated individuals can expose or contaminate other people with whom they come in close contact and should avoid contact with others until they are decontaminated. People who have inhaled or ingested radioactive material require assistance by medical personnel.


There are no reliable antidotes once radioactive material is inhaled or ingested; however, symptoms can be treated. There are some chemicals that help cleanse the body of specific radioactive materials. Prussian blue has been proven effective for cesium-137 ingestion. Potassium iodide (KI) tablets are recommended only for exposure to iodine-131 (I-131), a short-lived radioactive element produced in nuclear power plants. Trained medical professionals will determine how to treat symptoms.

Last Published Date: August 9, 2012
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