What is dirty bomb?

A “dirty bomb” is not a nuclear weapon or bomb, the type of which was exploded over Hiroshima and Nagasaki, Japan. Dirty bomb is also called as “radiological dispersal device” (RDD) that combines a conventional explosive, such as dynamite, with radioactive material. Most RDDs would not release enough radiation to kill people or to cause radiation induced severe illness. However, the effects of the conventional explosive itself would be more harmful to individuals than the radioactive material.

Terrorist organizations may use this type of explosion to create panic and fear amongst the target population groups. Making prompt, accurate information available to the public could prevent the panic situation sought by terrorist organizations.

However, depending on the scenario, RDD explosion could create fear and panic due to the radioactive part of the bomb. This is the main motive behind using radioactive material in the conventional bomb. The explosion will contaminate property, may be a few blocks or a few kilometers depending upon the quantity, type of radioactive material used, method used for the dispersal and the weather conditions at that point of time. The clean up of the contamination is potentially costly, need expert’s guidance and time consuming.

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. There are expert groups identified by the government to respond to such type of emergencies within minutes. Media such as television and mobile messaging system come handy in informing the public as to the protective actions to be taken to minimize the exposure to radiation. The experts also will asess the radiation dose received by the exposed persons and suggest remedial measures, if required.

Thumb rules for the protection are: i) minimize the time spent near the affected area and ii) keep sufficient distance from the site of contamination. The inhalation of the airborne radioactive material can be prevented by using a wet handkerchief over the nose or a respirator normally used by the hospital staff.