A Radiological Dispersion Device (RDD) combines a conventional explosive device—such as a bomb—with radioactive material. It is designed to scatter dangerous amounts of radioactive material over a general area.
RDDs cause psychological fear and economic disruption. Some devices could cause fatalities from exposure to radioactive materials. Depending on the speed at which the area of the RDD detonation was evacuated or how successful people were at sheltering-in-place, the number of deaths and injuries from an RDD might not be substantially greater than from a conventional bomb explosion.
The size of the affected area and the level of destruction caused by an RDD would depend on the sophistication and size of the conventional bomb, the type of radioactive material, the quality and quantity of the radioactive material, and the local meteorological conditions, primarily wind and precipitation. The area affected could be placed off-limits to the public for several months during cleanup efforts.
- There is no way of knowing how much warning time there will be before an RDD attack, so being prepared in advance and knowing what to do and when is important.
- Build an emergency go kit, which includes items like non-perishable food, water, a battery-powered or hand-crank radio, flashlights, batteries, duct tape and scissors.
- Make a family communication plan. Your family may not be together when disaster strikes, so it is important to know how you will contact one another, how you will get back together and what you will do in case of an emergency.
- Inquire about emergency plans at places where your family spends time: work, daycare and school. If no plans exist, consider volunteering to help create one.
- Choose an internal room to shelter, preferably one without windows.
- If you live in an apartment building or high-rise, talk to the manager about the safest place in the building for sheltering and about providing for building occupants until it is safe to go out.
- While the explosive blast will be immediately obvious, the presence of radiation will not be known until trained personnel with specialized equipment are on the scene.
- Whether you are indoors or outdoors, home or at work, be extra cautious. It would be safer to assume radiological contamination has occurred—particularly in an urban setting or near other likely terrorist targets—and take the proper precautions. As with any radiation, you want to avoid or limit exposure.
- If there is visual dust or other contaminants in the air, breathe though the cloth of your shirt or coat to limit your exposure. If you manage to avoid breathing radioactive dust, your proximity to the radioactive particles may still result in some radiation exposure.
- Seek shelter indoors immediately in the nearest undamaged building preferably underground or in an interior room of a building, placing as much distance and dense shielding as possible between you and the outdoors where the radioactive material may be.
- If appropriate shelter is not available, cover your nose and mouth and move as rapidly as is safe upwind, away from the location of the explosive blast. Then, seek appropriate shelter as soon as possible. Listen for official instructions and follow directions.
- If you have time, turn off ventilation and heating systems, close windows, vents, fireplace dampers, exhaust fans, and clothes dryer vents.
- Retrieve your disaster supplies kit and a battery-powered radio and take them to your shelter room.
- Seal windows and external doors that do not fit snugly with duct tape to reduce infiltration of radioactive particles.
- Plastic sheeting will not provide shielding neither from radioactivity nor from blast effects of a nearby explosion.
- Listen for official instructions and follow directions.
- After finding safe shelter, people who may have been exposed to radioactive material should decontaminate themselves.
- Remove and bag your clothing (and isolate the bag away from you and others).
- Shower thoroughly with soap and water.
- Seek medical attention after officials indicate it is safe to leave shelter.
- Contamination from an RDD could affect a wide area, depending on the amount of conventional explosives, the quantity and type of radioactive material released, and meteorological conditions. Radiation from an RDD will likely take longer to dissipate due to a potentially larger localized concentration of radioactive material.
- Listen to your radio or watch the television for instructions from local officials.
- Do not return to or visit an RDD incident location for any reason.