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Radiation hazard and protection for the nuclear weapon terrorism
International Congress Series 1276 (2005) 245 – 246
www.ics-elsevier.com
Radiation hazard and protection for the nuclear weapon terrorism Jun Takada* Medical School, Sapporo Medical University, Sapporo, Japan
Abstract. A radiation hazard is predicted in case of nuclear weapon terrorism on the surface. An effective radiation protection, in which 70% of victims may survive, is proposed. D 2004 Elsevier B.V. All rights reserved. Keywords: Nuclear weapon terrorism; Dosimetry; Radiation protection; Semipalatinsk test site
1. Introduction The possibility of nuclear weapon attack by terrorists (NWAT) occurring after September 11th 2001 may be considered as the most dangerous radiation hazard in the 21st century [1]. It is difficult for us to believe that the risk of nuclear attack, unrelated to war, may occur in a city of a developed nation. Emergency measures for radiation protection are one of the main topics regarding nuclear terrorism. For a 3-year period, we especially focused on the assessment of hazard and radiation protection in case of a terrorist attack with nuclear weapons. We studied field investigations of ground zero (GZ) of small weapons in Semipalatinsk Nuclear Test Site (SNTS). Here, we report dose fore-assessment and propose a method of radiation protection in case of 1 kt NWAT in a city. 2. Method Scientific information of the present report is based on our field research of nuclear weapon testing [1] in and out of ground zero and on the US reports on the effects of nuclear explosion [2]. We have radiation data on GZ of a small nuclear weapon which was exploded on the surface in SNTS. This provided us with information on residual radiation * Tel./fax: +81 11 644 2001. E-mail address: [email protected]. 0531-5131/ D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.ics.2004.11.089
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J. Takada / International Congress Series 1276 (2005) 245–246
hazards after the NWAT. Dose evaluation due to fallout was carried out in case of outdoors with no protection and in case of indoor sheltering and then evacuation with subway by using the USA scheme and certain parameters [2]. The small crater size in SNTS suggests the yield of NWAT less than 1 kt equivalent of TNT. In our evaluation of disasters of NWAT, we deal with a 1 kt weapon. 3. Result and discussion A nuclear explosion of 1 kt yield instantly becomes a fire ball with a diameter of about 70 m with a temperature of several million degrees by a nuclear fission chain reaction of plutonium. It occurs in a shock wave, a bomb blast and radiation such as heat radiation, gamma ray and neutrons at the same time. This may happen in a building such as a hotel in case of NWAT. A range of 500 m radius from GZ will be affected severely by shock wave. People in the 260 m zone will receive the third thermal injury. The initial nuclear radiation within a minute from the fire ball extends wider than heat radiation. People near ground zero in the 800 m zone will receive dose of level-A (lethal more than 50%).1 A huge amount of radioactive concrete particles containing fission products becomes a pillar several kilometers high above GZ. Consequently, the most dangerous impact for the population will be radioactive fallout in the case of NWAT. Areas of level-A, level-B and level-C may extend to 2, 4 and 12 km, respectively, in case of an hour outdoor stay in the fallout area. Therefore, this fallout will produce a very severe nuclear disaster and severe radiation hazard will remain in the lee area. Evacuation by subway following indoor sheltering as a protection method is very effective. Seventy percent of victims potentially with level-A radiation will be saved in this manner. Short-term nuclear hazard will remain at ground zero and cause late recovery work after several months or a year. Some measure should be carried out for long-term nuclear hazard such as Cs-137, Sr-90 as well as plutonium. References [1] Jun Takada, Nuclear Weapon Attack in Tokyo by Terrorists, Kodansha Tokyo, 2004 (in Japanese). [2] S. Glasstone, P.J. Dolan, The Effects of Nuclear Weapons, United States Department of Defense and the Energy Research and Development Administration, Washington, DC, 1977.
1 Dose level is classified into six grades, from A to F. Level-A with risk of lethality more than 50% (more than 4 Sv), level-B with risk of acute radiation sickness (more than 1 Sv), level-C with risk of embryo and late health effects, level-D with some safety zone, level-E safety zone (less than 1 mSv), level-F in relief.
www.ics-elsevier.com
Radiation hazard and protection for the nuclear weapon terrorism Jun Takada* Medical School, Sapporo Medical University, Sapporo, Japan
Abstract. A radiation hazard is predicted in case of nuclear weapon terrorism on the surface. An effective radiation protection, in which 70% of victims may survive, is proposed. D 2004 Elsevier B.V. All rights reserved. Keywords: Nuclear weapon terrorism; Dosimetry; Radiation protection; Semipalatinsk test site
1. Introduction The possibility of nuclear weapon attack by terrorists (NWAT) occurring after September 11th 2001 may be considered as the most dangerous radiation hazard in the 21st century [1]. It is difficult for us to believe that the risk of nuclear attack, unrelated to war, may occur in a city of a developed nation. Emergency measures for radiation protection are one of the main topics regarding nuclear terrorism. For a 3-year period, we especially focused on the assessment of hazard and radiation protection in case of a terrorist attack with nuclear weapons. We studied field investigations of ground zero (GZ) of small weapons in Semipalatinsk Nuclear Test Site (SNTS). Here, we report dose fore-assessment and propose a method of radiation protection in case of 1 kt NWAT in a city. 2. Method Scientific information of the present report is based on our field research of nuclear weapon testing [1] in and out of ground zero and on the US reports on the effects of nuclear explosion [2]. We have radiation data on GZ of a small nuclear weapon which was exploded on the surface in SNTS. This provided us with information on residual radiation * Tel./fax: +81 11 644 2001. E-mail address: [email protected]. 0531-5131/ D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.ics.2004.11.089
246
J. Takada / International Congress Series 1276 (2005) 245–246
hazards after the NWAT. Dose evaluation due to fallout was carried out in case of outdoors with no protection and in case of indoor sheltering and then evacuation with subway by using the USA scheme and certain parameters [2]. The small crater size in SNTS suggests the yield of NWAT less than 1 kt equivalent of TNT. In our evaluation of disasters of NWAT, we deal with a 1 kt weapon. 3. Result and discussion A nuclear explosion of 1 kt yield instantly becomes a fire ball with a diameter of about 70 m with a temperature of several million degrees by a nuclear fission chain reaction of plutonium. It occurs in a shock wave, a bomb blast and radiation such as heat radiation, gamma ray and neutrons at the same time. This may happen in a building such as a hotel in case of NWAT. A range of 500 m radius from GZ will be affected severely by shock wave. People in the 260 m zone will receive the third thermal injury. The initial nuclear radiation within a minute from the fire ball extends wider than heat radiation. People near ground zero in the 800 m zone will receive dose of level-A (lethal more than 50%).1 A huge amount of radioactive concrete particles containing fission products becomes a pillar several kilometers high above GZ. Consequently, the most dangerous impact for the population will be radioactive fallout in the case of NWAT. Areas of level-A, level-B and level-C may extend to 2, 4 and 12 km, respectively, in case of an hour outdoor stay in the fallout area. Therefore, this fallout will produce a very severe nuclear disaster and severe radiation hazard will remain in the lee area. Evacuation by subway following indoor sheltering as a protection method is very effective. Seventy percent of victims potentially with level-A radiation will be saved in this manner. Short-term nuclear hazard will remain at ground zero and cause late recovery work after several months or a year. Some measure should be carried out for long-term nuclear hazard such as Cs-137, Sr-90 as well as plutonium. References [1] Jun Takada, Nuclear Weapon Attack in Tokyo by Terrorists, Kodansha Tokyo, 2004 (in Japanese). [2] S. Glasstone, P.J. Dolan, The Effects of Nuclear Weapons, United States Department of Defense and the Energy Research and Development Administration, Washington, DC, 1977.
1 Dose level is classified into six grades, from A to F. Level-A with risk of lethality more than 50% (more than 4 Sv), level-B with risk of acute radiation sickness (more than 1 Sv), level-C with risk of embryo and late health effects, level-D with some safety zone, level-E safety zone (less than 1 mSv), level-F in relief.