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Radiological Emergencies

People are exposed to small amounts of radiation every day, both from naturally occurring sources (such as elements in the 
soil or cosmic rays from the sun), and man-made sources. Man-made sources include some electronic equipment (such as 
microwave ovens and television sets), medical sources (such as x-rays, certain diagnostic tests, and treatments), and from 
nuclear weapons testing.

The amount of radiation from natural or man-made sources to which people are exposed is usually small; a radiation 
emergency (such as a nuclear power plant accident or a terrorist event) could expose people to small or large doses of 
radiation, depending on the situation.
 
What Happens When People Are Exposed to Radiation?
Radiation can affect the body in a number of ways, and the adverse health effects of exposure may not be apparent for many 
years.These adverse health effects can range from mild effects, such as skin reddening, to serious effects such as cancer and death, 
depending on the amount of radiation absorbed by the body (the dose), the type of radiation, the route of exposure, and the 
length of time a person was exposed.

Contamination refers to particles of radioactive material that are deposited anywhere that they are not supposed to be, such as 
on an object or on a person’s skin. Internal contamination refers to radioactive material that is taken into the body through breathing, eating, or drinking.

Exposure occurs when radiation energy penetrates the body.Exposure to lower doses of radiation may lead to an increased risk of developing cancer or other adverse health effects later 
in life. Exposure to very large doses of radiation may cause death within a few days or months.
 
What Types of Terrorist Events Might Involve Radiation?
Possible terrorist events could involve introducing radioactive material into the food or water supply, using explosives (like 
dynamite) to scatter radioactive materials (called a “dirty bomb”), bombing or destroying a nuclear facility, or exploding a 
small nuclear device.

Although introducing radioactive material into the food or water supply most likely would cause great concern or fear, it 
probably would not cause much contamination or increase the danger of adverse health effects.

Although a dirty bomb could cause serious injuries from the explosion, it most likely would not have enough radioactive 
material in a form that would cause serious radiation sickness among large numbers of people. However, people who were 
exposed to radiation scattered by the bomb could have a greater risk of developing cancer later in life, depending on their 
dose.

A meltdown or explosion at a nuclear facility could cause a large amount of radioactive material to be released. People at the 
facility would probably be contaminated with radioactive material and possibly be injured if there was an explosion. Those 
people who received a large dose might develop acute radiation syndrome. People in the surrounding area could be exposed 
or contaminated.

Clearly, an exploded nuclear device could result in a lot of property damage. People would be killed or injured from the blast 
and might be contaminated by radioactive material. Many people could have symptoms of acute radiation syndrome. After a 
nuclear explosion, radioactive fallout would extend over a large region far from the point of impact, potentially increasing 
people’s risk of developing cancer over time.

What Preparations Can I Make for a Radiation Emergency?
Your community should have a plan in place in case of a radiation emergency. Check with community leaders to learn more 
about the plan and possible evacuation routes.

Check with your child’s school, the nursing home of a family member, and your employer to see what their plans are for 
dealing with a radiation emergency.
 
Develop your own Family Emergency Plan so that every family member knows what to do.

At home, put together an Emergency Kit  that would be appropriate for any emergency.

How Can I Protect Myself During a Radiation Emergency?
After a release of radioactive materials, local authorities will monitor the levels of radiation and determine what protective 
actions to take. The most appropriate action will depend on the situation. Tune to the local emergency response network or news station for 
information and instructions during any emergency.
 
If a radiation emergency involves the release of large amounts of radioactive materials, you may be advised to “shelter in 
place,” which means to stay in your home or office; or you may be advised to move to another location.
If you are advised to shelter in place, you should do the following:
  • Close and lock all doors and windows.

  • Turn off fans, air conditioners, and forced-air heating units that bring in fresh air from the outside. Only use units to recirculate air that is already in the building.

  • Close fireplace dampers.

  • If possible, bring pets inside.

  • Move to an inner room or basement.

  • Keep your radio tuned to the emergency response network or local news to find out what else you need to do.
If you are advised to evacuate, follow the directions that your local officials provide. Leave the area as quickly and orderly as possible and take your Emergency Kit
Take pets only if you are using your own vehicle and going to a place you know will accept animals. Emergency vehicles and 
shelters usually will not accept animals.

Last updated May 20, 2015