Air Crash

Figure 1.4.3-1 from WASH-1400 compares the risk of 100 nuclear plants with other man-caused risks. This is a CCDF that gives the frequency per year that accidents will L-xcccd a value on the abscissa. For example, for 100 fatalities, the frequency that 100 nuclear power plants could do this is lE-4, air crashes to persons on the ground lE-2, chlorine releases 1. IE-2, dam failures 7E-2, explosions SF-2, fires 1. IE-1, air crashes (total) 5E-1, and total man-caused 9E-1,... 

This figure presents only the so-called internal events. Not included are the "V" sequences (valve rupture that bypasses containment), earthquake, fire, Hood, tornado and air crash,... 

Force majeure is an event, circumstances, or an effect that cannot be reasonably anticipated or controlled - often called an act of God, which includes natural disasters caused by weather and land movement. Force majeure also includes war, riots, air crash, labor stoppage, illness, disruption in utility supply by service providers, etc. There is some contradiction in this requirement as you can take effective action to maintain business continuity as a result of certain events that may be classified as force majeure or natural disasters. 

But just as an air crash does not mean the end of commerical aviation, neither does the damage caused by improper use of certain substances mean the end of the chemical industry. The image of chemicals is tarnished, however. Citizens who deliberately risk their own death, when they are not actually killing others, because of speeding on the roads or because they are addicted to alcohol, tobacco, or drugs, are less and less inclined, for all that, to accept accidental security breaches when these are not caused by themselves. 

Protection of materials, storage, plant access, and other critical areas against earthquakes, hurricanes, tornadoes, vandalism, air crashes, sabotage, etc., to practical limits... 

Mohler, S.R. (1975). Air crash survival injuries and evacuation fi-om toxic hazards. Space Environ. Med. 46 86-8. 

An amount of 3.7 kg plutonium is also reported as typical for pits in U.S. and USSR devices. Corroborating evidence is given in a Russian report on early tests (Dubasov et al., 1995) for example, which describes many devices with 3-4 kg of plutonium, and in press reports that refer to nearly 3 kg of plutonium in each of 32 USSR nuclear warheads in a sunken submarine east of Bermuda. Similar values have been reported for the two torpedoes that sank with the Russian submarine Komsomolets north of Norway in 1989, and for the U.S. weapons involved in the air crashes at Thule and Palomares in the 1960s. 

John K. Stille was a professor of chemistry at Colorado State University until his untimely death in 1989 in a commercial air crash on his way to a scientific meeting in Switzerland. 

HADJIANTONION, A., ARMIRIOTIS, J., ZANNOS, A., The performance of Type A packaging under air crash and fire accident conditions , ibid. 

The ABV reactor plant containment is a steel leak-tight shell designed for the ultimate pressure and tempo ature arising in beyond deagn accidents. Protection against external impacts (e g. air crash) is provided by a special protective enclosure compartment in a floating NPP, or by the reactor building structure in a land-based NPP. 

The tanks of the emergency heat removal system are arranged in annexes to the reactor building on opposite sides of the containment thus excluding their simultaneous failure by air crash or shock wave impact. 

As the name suggests Fig. 11/3.7.2-1 is like an event tree diagram, which shows various decisions and actions concerned people are expected to do. This operator action tree is mainly used for post accident cases to pinpoint an operator s failure. This is very much used in accident analysis in air crashes. The level of breakdown of the main task is crucial. Too many breakdowns may pose a problem in handling. From visual inspection it is possible to identify the crucial operation that can initiate the event. The figure will give a clearer idea. 

Second, modem terrestrial industries are following the trend, begun in aviation, of the extensive use of computer control. Hence, hazardous industries must be assiduous about learning from aviation experiences. Already, there have been several major air crashes where the causes of the accidents are at least partly due to issues arising from their computer systems. 

What follows is a brief description of three separate air crashes, which took place over 13 years, featuring two completely different designs of airliner (the Boeing 757 and the Airbus 330), and yet the accidents had some similar circumstances. All three accidents were thoroughly investigated and are well documented, and each has even been the subject of its own television documentary. 

In siting research reactors, as for all other nuclear installations, serious consideration is given to minimizing the effects of the site on the reactor and the reactor on the site, i.e, the effects of extreme external events, both natural and man-made (earthquake, floods, air crashes, chemical explosions etc.), and the potential impact of the reactor on the environment. 

The site should be located in an area where the risk of air crash is not significant. 

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