|
A dirty bomb or radiological dispersal device (RDD) is a speculative radiological weapon that combines radioactive material with conventional explosives. The purpose of the weapon is to contaminate the area around the dispersal agent/conventional explosion with radioactive material, serving primarily as an area denial device against civilians. It is however not to be confused with a nuclear explosion, such as a fission bomb, which by releasing nuclear energy produces blast effects far in excess of what is achievable by the use of conventional explosives. Though a radiological dispersal device (RDD) would be designed to disperse radioactive material over a large area, a bomb that uses conventional explosives and produces a blast wave would be far more lethal to people than the hazard posed by radioactive material that may be mixed with the explosive.〔http://www.bioterrorism.slu.edu/bt/products/ahec_rad/ppt/Dirty%20Bomb.ppt〕 At levels created from probable sources, not enough radiation would be present to cause severe illness or death. A test explosion and subsequent calculations done by the United States Department of Energy found that assuming nothing is done to clean up the affected area and everyone stays in the affected area for one year, the radiation exposure would be "fairly high", but not fatal.〔http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/fs-dirty-bombs.html〕 Recent analysis of the nuclear fallout from the Chernobyl disaster confirms this, showing that the effect on many people in the surrounding area, although not those in close proximity, was almost negligible.〔(【引用サイトリンク】title=BBC NEWS - Science/Nature - Chernobyl's 'nuclear nightmares' )〕 Since a dirty bomb is unlikely to cause many deaths by radiation exposure, many do not consider this to be a weapon of mass destruction.〔 Its purpose would presumably be to create psychological, not physical, harm through ignorance, mass panic, and terror. For this reason dirty bombs are sometimes called "weapons of mass disruption". Additionally, containment and decontamination of thousands of victims, as well as decontamination of the affected area might require considerable time and expense, rendering areas partly unusable and causing economic damage. == Dirty bombs and terrorism == Since the 9/11 attacks the fear of terrorist groups using dirty bombs has increased significantly, which has been frequently reported in the media.〔Petroff (2007)〕 The meaning of terrorism used here, is described by the U.S. Department of Defense's definition, which is "the calculated use of unlawful violence or threat of unlawful violence to inculcate fear; intended to coerce or to intimidate governments or societies in the pursuit of goals that are generally political, religious, or ideological objectives".〔(【引用サイトリンク】title=404w DTIC Maintenanc )〕 There have only ever been two cases of caesium-containing bombs, and neither was detonated. Both involved Chechnya. The first attempt of radiological terror was carried out in November 1995 by a group of Chechen separatists, who buried a caesium-137 source wrapped in explosives at the Izmaylovsky Park in Moscow. A Chechen rebel leader alerted the media, the bomb was never activated, and the incident amounted to a mere publicity stunt.〔King (2004); (NOVA, Chronology of events )〕 In December 1998, a second attempt was announced by the Chechen Security Service, who discovered a container filled with radioactive materials attached to an explosive mine. The bomb was hidden near a railway line in the suburban area Argun, ten miles east of the Chechen capital of Grozny. The same Chechen separatist group was suspected to be involved.〔Edwards (2004); (NOVA, Chronology of events )〕 Despite the increased fear of a dirty bombing attack, it is hard to assess whether the actual risk of such an event has increased significantly.〔Frost (2005)〕 The following discussions on implications, effects and probability of an attack, as well as indications of terror groups planning such, are based mainly on statistics, qualified guessing and a few comparable scenarios. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dirty bomb」の詳細全文を読む スポンサード リンク
|