Nuclear power catastrophes

Ten years passed since the biggest radioactive catastrophe in the history of humanity happened at the Chernobyl nuclear power plant. The Russian State medical dosimetric Register was founded after this catastrophe At present in the Register they keep a medical and radiation-dosimetric information about 435.276 persons. 

The NPRDS is an industry-wide system for monitoring the performance of selected systems and components at U.S. commercial nuclear power plants. Information in NPRDS is derived from a standardized format input report prepared by U.S. nuclear plant licensees. The plants are as)ced to submit failure reports on catastrophic events and degraded failures within the defined reportable scope reporting of incipient events is optional. Command faults are not reportable unless they malce an entire system unavailable. In addition, the plants are as)ced to file component engineering reports on all components within the selected systems and reportable scope. These reports contain detailed design data, operating characteristics, and performance data on the selected systems and components (over 3000 components, from approximately 30 systems, per unit). The selected systems are primarily safety systems. 

In the analysis of pumps, IPRDS failure data for 60 selected pumps at four nuclear power plants were statistically analyzed using FRAC. The data cover 23 functionally different pumps, respectively, for two BWRs. Catastrophic, degraded, and incipient failure severity categories were considered for both demand-related and time-dependent failures. 

Indeed, when new countries like the U K. France or China became nuclear powers, countries which were already members of the club were strongly opposed, but now it is quite well accepted that possession of nuclear weapons by those countries did not provoke a catastrophe. Some even consider that the existence of nuclear weapons in different camps was a stabilizing factor during the Cold War and prevented a major conflict during the past half-century. Why, then, the possession by India should not stabilize the relation between India and China, and by Pakistan the relation between Pakistan and India, preventing major conflicts in these zones At least the question may be asked. In the same way, the possession by Israel of nuclear weapons, in the opinion of some, has stabilized the situation in the Middle East. In any case, when a country has decided that it is worth while to make the effort and take the risks of developing nuclear weapons, it seems that after some initial outcry, the world accepts it without major retaliation That shows some kind of hypocrisy in the initial claim of a fundamental evil connected with the proliferation of nuclear weapons. The real issue is probably to avoid the acquisition of nuclear weapons by unstable, not very democratic countries. May be Pakistan is in that category clearly the West would not like Libya or Iran and Iraq to possess such weapons. A real, major issue is full nuclear disarmament, but this is another story. 

Environmentally hazardous projects are those where the risk of accidents is very high, which can result in a major and sometimes even catastrophic chemical pollution of the environment. Frequently, these disasters take casualties among the plant personnel, as well as among the nearby settlements population, which were the cases with the Chernobyl Nuclear Power Plant disaster in Ukraine, or with the pesticide plant accident in Bhopal, India. 

One concern about nuclear power plants, of course, is an echo of the world s first exposure to nuclear power, the atomic bomb blasts. Many people fear that a nuclear power plant may go out of control and explode like a nuclear weapon. In spite of experts insistence that such an event is impossible, a few major disasters have perpetuated the fear of nuclear power plants exploding or failing catastrophically in some other mode. Although commercial nuclear power plants cannot explode, they have a demonstrated potential to pass out of the control of their operators, with unpredictable consequences. By far the most serious of those events was the explosion that occurred at the Chernobyl nuclear power plant near Kiev in the Ukraine in 1986. 

The reverse would be that insurance and other financial institutions would require demonstration of higher safety performance as a prerequisite for financing or underwriting risks. For example, in order to operate, nuclear power plants in the United States must demonstrate sufficient financial assurance to satisfy liability claims of members of the public for personal injury and property damage in the event of a catastrophic nuclear accident. Such insurance is available through the American Nuclear Insurers, which evaluates plant performance against objectives, criteria, and guidelines developed in conjunction with the U.S. NRC and the Institute of Nuclear Power Operations. A plant must receive a favorable report from this review before it can be insured. 

In case of any event that clearly deviates form normal behavior of a reactor (ranging from observations with safety implications to catastrophes), the event should be reported to IAEA and the appropriate organizations in other coimtries. For reports to the press and to the general public of safety related events in nuclear power plants IAEA and OECD/NEA recommend the INES scale, see Table 19.6. 

The only type of risk that is unique to nuclear power is the risk of a catastrophe such as the Chernobyl disaster of 1996. The potential third-party liability of such events is so high that such risks are uninsurable in normal markets. The US introduced government insurance of nuclear plants with the Price-Anderson Act of 1957 (Rothwell, 2002). In the UK, nuclear operators liability is capped under the provision of the Nuclear Installations Act 1965 and the Energy Act 1983, which implement the international convention on third-party liability signed in Paris in 1960 and Brussels in 1966 (OECD, 2003). 

Just 8 years later, the reactors at the Fukushima nuclear power plant catastrophe released enough radioactivity that it is plausible that some of the people in the nearby communities will sicken, and some of them will die. 

The Report to the President concerning the Deepwater Horizon catastrophe discussed the creation of an industry-sponsored agency analogous to the nuclear industry s independent Institute of Nuclear Power Operations (INPO) that was created in the wake of the Three Mile Island event. The President s Commission to do with that event said the following. 

A balance must be struck between industrial development and the energy required in order to build self-contained national economies. At one time, oil-fuel and then nuclear power were considered to be the answer to the world energy demands. These assumptions were proved to be inadequate because of (1) the unrest and armed hostile conflicts in the Middle East affecting oil supplies and (2) the catastrophic nuclear accidents in various parts of the world, which have justifiably or unjustifiably—it is not the purpose of this text to decide on the viability of energy from nuclear sources— posed serious questions on the viability and safety of the nuclear industry. 

The second type of prognosis is for situations where a failure is catastrophic (e.g., in nuclear power plants). It is desirable to predict the probability that a machine operates without failure up to some future time (e.g., next inspection interval), given the current machine condition and past operation profile. Actually, in any situation, the probability that a machine operates without failure until next inspection (or condition monitoring) interval is a good reference for maintenance persoimel to decide whether or not the inspection interval is appropriate. 

The two most severe cases of catastrophic failure of nuclear power plants, Chernobyl in 1986 and Fukushima in 2011, are not good case studies for exposure... 

Radioactive iodine isotopes are spread as a result of nuclear power plant disasters. Especially important is with a half-life of eight days. When this iodine isotope is taken up by the thyroid gland, it causes cancer. People Kving and working near a nuclear power station are therefore recommended to have iodine tablets available and to use them in an emergency situation. The tablet s content of normal iodine is taken up by the thyroid gland and saturates it This blocks the uptake of radioactive iodine. After the Chernobyl catastrophe, the intake of dairy products enriched with iodine is of particular importance for the population of Ukraine s western regions. 

To comprehend risk, we must understand that we can have an unsafe event and the risk could still be low. Remember if you lower the probability of occurrence to a very small number, then even a catastrophic event (e.g., radioactive fallout from a nuclear power plant) can still be a low risk to the public. That brings the real challenge to engineers, which is to decide how safe is safe enough. 

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