Tundraco's Daily Living Guide to Emergency Preparedness
Backgrounder on Dirty Bombs
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Tundraco's Daily Living Guide to Emergency Preparedness Backgrounder on Dirty Bombs |
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A “dirty bomb” is one type of a “radiological dispersal device” (RDD)
that combines a conventional explosive, such as dynamite, with radioactive material.
The terms dirty bomb and RDD are often used interchangeably in the media. Most
RDDs would not release enough radiation to kill people or cause severe illness
- the conventional explosive itself would be more harmful to individuals than the
radioactive material. However, depending on the scenario, an RDD explosion could
create fear and panic, contaminate property, and require potentially costly cleanup.
Making prompt, accurate information available to the public could prevent the panic
sought by terrorists.
A dirty bomb is in no way similar to a nuclear weapon or nuclear bomb. A nuclear
bomb creates an explosion that is millions of times more powerful than that of
a dirty bomb. The cloud of radiation from a nuclear bomb could spread tens to hundreds
of square miles, whereas a dirty bomb’s radiation could be dispersed within
a few blocks or miles of the explosion. A dirty bomb is not a “Weapon of
Mass Destruction” but a “Weapon of Mass Disruption,” where contamination
and anxiety are the terrorists’ major objectives.
The extent of local contamination would depend on a number of factors, including the size of the explosive, the amount and type of radioactive material used, the means of dispersal, and weather conditions. Those closest to the RDD would be the most likely to sustain injuries due to the explosion. As radioactive material spreads, it becomes less concentrated and less harmful. Prompt detection of the type of radioactive material used will greatly assist local authorities in advising the community on protective measures, such as sheltering in place, or quickly leaving the immediate area. Radiation can be readily detected with equipment already carried by many emergency responders. Subsequent decontamination of the affected area may involve considerable time and expense.
Immediate health effects from exposure to the low radiation levels expected from an RDD would likely be minimal. The effects of radiation exposure would be determined by:
The health effects of radiation tend to be directly proportional to radiation dose. In other words, the higher the radiation dose, the higher risk of injury.
Protective ActionsIn general, protection from radiation is afforded by:
More detailed guidance is provided in the questions and answers at the end of this Backgrounder.
Sources of Radioactive MaterialRadioactive materials are routinely used at hospitals, research facilities, industrial and construction sites. These radioactive materials are used for such purposes as diagnosing and treating illnesses, sterilizing equipment, and inspecting welding seams. The Nuclear Regulatory Commission together with 33 “Agreement” States, which also regulate radioactive material, administer over 21,000 licenses of such materials. The vast majority of these materials are not useful as an RDD.
Control of Radioactive MaterialNRC and State regulations require owners licensed to use or store radioactive material to secure it from theft and unauthorized access. These measures have been greatly strengthened since the attacks of September 11, 2001. Licensees must promptly report lost or stolen high-risk radioactive material. Local authorities also assist in making a determined effort to find and retrieve such sources. Most reports of lost or stolen material involve small or short-lived radioactive sources not useful for an RDD.
Past experience suggests there has not been a pattern of collecting such sources for the purpose of assembling an RDD. It is important to note that the radioactivity of the combined total of all unrecovered sources over the past 5 years (when corrected for radioactive decay) would not reach the threshold for one high-risk radioactive source. Unfortunately, the same cannot be said world-wide. The U.S. Government is working to strengthen controls on high-risk radioactive sources both at home and abroad.
Risk of CancerJust because a person is near a radioactive source for a short time or gets a small amount of radioactive dust on himself or herself does not mean he or she will get cancer. Any additional risk will likely be extremely small. Doctors specializing in radiation health effects will be able to assess the risks and suggest mitigating medical treatment, once the radioactive source and exposure levels have been determined.
There are some medical treatments available that help cleanse the body of certain radioactive materials. Prussian blue has been proven effective for ingestion of cesium-137 (a radioactive isotope). In addition, potassium iodide (KI) can be used to protect against thyroid cancer caused by iodine-131 (radioactive iodine). However, KI, which is available as a “over the counter” pill, offers no protection to other parts of the body or against other radioactive isotopes. Medical professionals are best qualified to determine how to best treat symptoms.
Other Contact informationA number of Federal agencies have responsibilities for dealing with RDDs. Their public affairs offices can answer questions on the subject or provide access to experts in and out of government. Their web sites and phone numbers are:
Department of Homeland Security: www.dhs.gov;
tel 202-282-8010.
Department of Energy: www.energy.gov/ tel 202-586-4940.
Environmental Protection Agency: www.epa.gov; tel 202-564-9828.
Nuclear Regulatory Commission: www.nrc.gov; tel 301-415-8200.
Federal Emergency Management Agency: www.fema.gov; tel 202-646-4600.
Department of Justice: www.usdoj.gov; tel 202-514-2007.
Federal Bureau of Investigation: www.fbi.gov; tel 202-324-3691.
Department of Health and Human Services: www.hhs.gov; tel 202-690-6343.
Transportation Security Administration: www.tsa.gov/public/; tel 571-227-2829.
National Nuclear Security Administration: www.nnsa.doe.gov/; tel 202-586-7371.
What is an RDD or “Dirty Bomb”?
A “dirty bomb” is one type of a “radiological dispersal device” (RDD) that combines a conventional explosive, such as dynamite, with radioactive material that may disperse when the device explodes. It is not the same as a nuclear weapon. If there are casualties, they will be caused by the initial blast of the conventional explosive. The radioactive particles that are scattered as a result of the explosion causes the "dirty" part. The explosives in such a bomb would still be more dangerous than the radioactive material.
What is radiation?
Radiation is a form of energy that is present all around us. Some of the Earth’s background radiation comes from naturally occurring radioactive elements from space, the soil, and the sun, as well as from man-made sources, like x-ray machines. Different types of radiation exist, some of which have more energy than others, and some of which can be more harmful than others. The dose of radiation that a person receives is measured in a unit called a "rem." A rem is a measure of radiation dose, based on the amount of energy absorbed in a mass of tissue. For example, an average person gets about 1/3 of a rem from exposure to natural sources of radiation in one year, and approximately 1/100th of a rem from one chest x-ray.
Will an RDD make me sick?
The effects of an RDD can vary depending on what type of radioactive material is used and how much material is scattered. It is very difficult to design an RDD that would deliver radiation doses high enough to cause immediate health effects or fatalities in a large number of people. For the most part, an RDD would most likely be used to
How can I protect myself in a radiation emergency?
If an explosion occurs, it may not be known immediately that radioactive material is involved. If you are made aware that you are near the site of an RDD or potential release of radioactive material, you should:
If you are advised to take shelter, whether it is at home or in an office, you should:
Questions such as when it’s safe to leave a building or return home, what is safe to drink and when, along with how children will be cared for if they are separated from their parents, will be answered by authorities who will be making decisions on a case-by-case basis depending on the information available at the time.
If I’m told NOT to take public transportation when evacuating from an RDD attack, what about using my personal vehicle?
Depending on where you are with respect to the location of the explosion, if you drive a car or truck, some radioactive material may get inside your vehicle, and will have to be cleaned out. Listen to emergency broadcasts for instructions about cleaning your vehicle. If you drive a private vehicle, do not run the heater or air conditioner.
I was a mile from the explosion -- am I going to be sick?
Listen to the emergency broadcast information. Instructions will be given based on the size of the attack, direction of the wind, and the components of the explosion. It is extremely unlikely that anyone who survives the explosion will become sick from radiation. In addition, your ability to have children will not be affected.
Will it be safe to clean my home and continue to live in it during and after such an RDD explosion?
Yes. Cleaning up the radioactive material (called decontamination) is certainly possible, and with reasonable effort and care, you should be able to return to a normal, safe life in your home or work.
Should I buy a radiation detector?
No. Unless you have been trained, you won’t be able to interpret the readings. Many of the Geiger counters available commercially are uncalibrated and worthless.
Should I purchase potassium iodide tablets for protection against radiation?
Potassium iodide (KI), which is available over the counter, protects people from thyroid cancer caused by radioactive iodine, a type of radioactive material that can be released in nuclear explosions, and depending on the amount released, can later cause thyroid cancer. KI should only be taken in a radiation emergency that involves the release of radioactive iodine. Since the use or release of radioactive iodine from an RDD is highly unlikely, KI pills would not be useful.
Always consult your doctor for medical advice.
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