電子期刊

ISSN:1684-193X

Abstract

History of Radiation Incidents

According to the CATS (Consequences Assessment Tool Set) software created by the US Federal Emergency Management Agency and the Defense Threat Reduction Agency, the expected casualties from a 12.5 kiloton nuclear explosion at ground level in New York City was calculated. The blast and thermal effects of such an explosion would kill 52,000 people immediately, and direct radiation would cause 44,000 cases of radiation sickness, of which 10,000 would be fatal. Radiation from fallout would kill another 200,000 people and cause several hundred thousand additional cases of radiation sickness.⁷
Casualties on this scale would immediately overwhelm medical facilities leading to a high mortality rate among those injured but not killed by the initial blast and thermal effects. Over 1000 hospital beds would be destroyed by blast, and 8700 beds would be in areas with radiation exposures high enough to cause radiation sickness.⁷ The remaining local medical facilities would quickly be overwhelmed, and the advance outside help would be delayed. For example, after the 1995 earthquake in Kobe, Japan, in which 6500 died and 34900 were injured, there were long delays before outside medical assistance arrived,⁸  and this disaster had few of the complicating factors that would accompany a nuclear attack with extensive radioactive contamination.

Ionizing radiation can produce charged particles (ions) in any material it strikes. X-rays, for example, are a form of ionizing radiation. At high doses, these charged particles can cause damage to molecules, cells, or tissue. Although different types of nuclear weapons or materials will emit various kinds of radiation, alpha, beta particles, gamma rays and neutrons are the types most likely to be encountered after a nuclear terrorist attack. Alpha particles are large, heavy, charged particles containing two protons and two neutrons. The ability of penetrate is poor, causing minimal external radiation. Beta particles are small, light, charged particles found in radioactive fallout. The ability of penetrate is fair, causing similar to thermal burns. Gamma rays are uncharged, highly energetic photons similar to X-rays. The ability of penetrate is high, causing whole-body exposure. Neutrons are uncharged particles with virtually the same mass as a proton. They are emitted during nuclear detonations, but are not present in fallout. Due to their mass, they can cause significant biological damage---up to twenty times the damage caused by gamma ray. The effects of radiation depend on whether the patient was exposed or contaminated, and if contaminated, how much radiation the patient has absorbed.
The effects that radiation depends on how much radiation the contaminated patient has absorbed. This amount of absorbed radiation used to be measured in rads-radiation absorbed doses. It's now measured by the gray (Gy). One Gy equals 100 rads.
Patients who absorb less than 0.75 Gy are not likely to experience any symptoms of exposure. Those who absorb more than 0.75 Gy can develop acute radiation syndrome.(ARS)(9) A dose of 30 Gy or more is always fatal.⁹

The assessment of the risk itself, consisting in interpreting the product of the probability of occurrence with the effects, is important. It is not an easy case, because quite different quantities have to be multiplied. The risk assessment of radiological terrorism shown in Table.¹⁰
Despite the fact that the damage of a successful nuclear weapon would be disastrous, the risk is extremely low probability. Although still difficult and a high-tech-business to RDD or dirty bomb, radiological terrorism is incomparably more feasible than the other cases. The scale of possible effects is lower, but the effects on the economics could be extremely large, and the psychological effects on the public would in any case be huge indeed.¹⁰

The Federal Radiological Emergency Response Plan (FRERP) set up an organized and integrated capability for timely, coordinated response by federal agencies to peacetime radiological emergencies. FRERP covers any peacetime radiological emergencies that has actual, potential, or perceived radiological consequences within the United States that could require a response by the federal government. The level of response is based on the type and quantity of radioactive material, the location of the emergency, the impact on the public and the environment, and the size of the affected area.
When the terrorists start the radiological terrorism, the Atomic Energy Act directs the Federal Bureau of Investigation (FBI) to investigate all alleged or suspected criminal violations of the act. In addition, the FBI is legally responsible for locating any nuclear weapon, device, or material and for restoring nuclear facilities to their rightful custodians. So, the FBI would be the lead federal agency for any terrorist event, and all other federal agencies would provide technical support and assistance to the FBI. The federal response would be adapted to the specific circumstances of the event. Agencies supporting the FBI include the Nuclear Regulatory Commission (NRC), the Department of Agriculture, the Department of Energy (DOE), the Department of Health and Human Services, the Department of Justice, the Federal Emergency Management Agency (FEMA), and the Environmental Protection Agency (EPA). Each supportive agency would coordinate and manage their technical portion of the response, and implement measures to protect public health and safety. The FBI would manage and direct law enforcement and intelligence aspects of the response, coordinating activities with appropriate federal, state, and local agencies within the framework of FRERP and as provided for in established interagency agreements or plans.⁶

When the terrorists start the radiological terrorism, the National Security Bureau (NSB) is authorized to convene Coordination Meeting for National Security Intelligence (CMNSI) to directs the Bureau of Investigation, Ministry of Justice and National police Administration, Ministry of Interior to investigate all alleged or suspected criminal violation of the act.
The Atomic Energy Council (AEC) of the Republic of China promulgated a nuclear emergency response plan in November 1981 under the approval of the Executive Yuan. The national nuclear Emergency management Committee (NNEMC) was also established. Efforts of all government authorities concerned have been integrated to organize a systematic arrangement for the nuclear emergency response plan. The responsibility of nuclear emergency planning and implementing are demarcated according to the site boundary. Taiwan Power Company is responsible for on-site areas under the supervision of the AEC. Central and local government agencies are responsible for off-site areas with the supports of TPC. This off-site nuclear organization is referred to as the NNEMC which comprises all government authorities concerned. NNEMC reports to the Executive Yuan and makes decisions on public protection actions, directs and coordinates the supporting center as well as the rescue center. The directing and coordinating center is composed of AEC and TPC personnel and subdivided into technical group, radiation monitoring team and logistic group with the responsibility of collecting and submitting accident information, assessing the accident consequences and dosage, monitoring and controlling off-site radiation and contamination, respectively. The rescue center is composed of relevant units of the local governments that is responsible for notifying and helping the public to take protective actions, arranging accommodations and providing medical care. The supporting center is composed of military units which are responsible for providing transportation means, carrying out decontamination in affected areas, and establishing temporal communication networks, traffic control and safeguard.

Linnemann RE. Soviet medical response to Chernobyl nuclear accident. JAMA 1987;258: 637-43