Complex Systems Are Very Likely to Experience Accidents
Many people in today’s industrial countries have experienced the frustration and inconvenience of having their car break down. That event, while troublesome, often does not pose any significant danger to people. It is a useful microcosm, however, because cars, like other complex systems, will almost certainly malfunction at some point during use. While we cannot prove the following assertion for sure, empirical data and observations strongly suggest that complex systems that are made of unreliable components will inevitably experience accidents so long as there exist flaws in the system that have no reliable safeguards. Numerous studies have investigated such a ‘Normal Accident Theory,’ and two notable cases very strongly indicate its validity: petroleum refinery accidents and the space shuttle Challenger, both of which will be discussed in this paper.
Normal Accident Theory (NAT) is the label for a school of thought that considers accidents in complex systems to be inevitable. Two characteristics of complex systems that are very important to NAT are the interactive complexity of a system and a system’s coupling. Coupling is determined primarily by the time between processes in a system, the independent or dependent progression of such processes, and the number of different ways that a system’s goal can be achieved (Piccard, 1999). Systems are classified as ‘tightly coupled,’ meaning that the time between processes is small, the processes are highly interdependent, and there are few paths, if not one, to the goal; or ‘loosely coupled,’ which is the opposite. These characteristics are particularly useful for comparing different complex systems and evaluating them to determine which are at the highest risk for accidents. The results can then be used to minimize, but not eliminate, the possibility that an accident will occur.
Sociologist Charles Perrow is generally credited with developing NAT. In order to understand the principles of NAT, several definitions that it uses are essential. An accident is defined as “an event that is unintended, unfortunate, damages people or objects, affects the functioning of the system of interest, and is non-trivial.” (Perrow, 1994) There are two types of accidents: component failure accidents, which “involve one or more component failures (part, unit, or subsystem) that are linked in an anticipated sequence,” and ‘normal accidents,’ or system accidents as they can be called (Perrow, 1994).
...ility of the experimental method is somewhat limited in that some outcomes cannot generalize into real world outcomes. The design method used was also expensive, since there are several pieces of equipment and tools that were required to complete the study. Further, the reliability of the study is limited in that it failed to identify and analyze the relative import of other factors that could lead to fatal accidents, such as localized infrastructure deficiencies. (DAlessio, Stolzenberg and Terry, Clinton, 1999).
According to “A Human Error Approach to Aviation Accident Analysis…”, both authors stated that HFACS was developed based off from the Swiss Cheese model to provide a tool to assist in the investigation process to identify the probable human cause (Wiegmann and Shappell, 2003). Moreover, the HFACS is broken down into four categories to identify the failure occur. In other words, leading up to adverse events the HFACS will identify the type error occur.
He was an opportunist, but not cynical. He believed that his ideas were beneficial to the society as a whole, so he did not only think about himself. He was an opportunist, no doubt, as he decided to take action and published the book The Starry Messenger that recorded his findings and observations of the stars and planet, thus changing the old mindset of the Earth being the only planet with satellites and the heliocentric theory. He also had plans ready in case opportunities turn up so he could grasp them. For example, when Baberini became the Pope and Bellarmine died, he immediately drafted a debate between the old sciences, which were Geocentrism and other beliefs that the Church had, and the new sciences, which were Heliocentrism and other things that Galileo discovered. He was a Catholic, and believed in searching for the truth of the world, thus he was not researching for his own sake, but for the world’s. In such circumstances, he was an opportunis...
“I have never met a man so ignorant that I couldn't learn something from him” (qtd. in “Nothing But the Facts About Galileo Galilei”). This was the adage that Galileo lived by. He consistently made it his purpose to understand and decipher the world for himself, and there was not a single person in the world that he was incapable of learning something from. During his youth, Galileo’s father had wanted him to study medicine in order to make a profitable living; at this urging, Galileo attended a medical university, but almost failed and ended up leaving without a degree. During his time at the university, however, he did make his first (and one of his most important) discoveries. He found that the period of each swing of a pendulum was exactly the same. This would come to be known as the law of the pendulum and would provide the basis for the regulation of clocks. A few more of his benefits to society came purely from the fact that he needed money in order to pay his debts. Some examples of what he threw together during these times of need include a rudimentary thermometer and both a military and civilian compas...
...ial approaches which are Normal Accident and HROs, although it seems certain that both of them tends to limit the progression that can contribute toward achieving to highly protective systems. This is because the scope of the problems is too narrow and the potential of the solutions is too limited as well. Hence, Laporte and Consolini et.al., (1991) as cited in Marais, et.al., (2004) conclude that the most interesting feature of the high reliability organization is to prioritize both performance and security by the managerial oversight. In addition, the goal agreement must be an official announcement. In essence, it is recommended that there is a continuing need in the high risk organizations for more awareness of developing security system and high reliability environment in order to gain highly successful method to lower risk in an advance technology system.
If equipment flaw or a defective part is spotted, the damaged machine directly stops, and operators halt production and rectify the identified problem. It is essential ...
The Space Shuttle Challenger disaster was one of the biggest space flight accidents and the result of a series of engineering failures. The Shuttle disintegrated after launch on its last mission, resulting in the death of its seven crew members. [1] The disaster happened on the Challenger program’s last launch on 28 January, 1986 at launch site Kennedy LC-39B. Later analysis showed that an O-ring, a seal on the right rocket boosted failed which was the cause of the accident. This incident is studied by engineers and organisations to see how effective communications can prevent engineering failures from causing catastrophic damages and how organisational ethics can be improved.
As a result a huge number of organisations have become software dependent. Some of these systems are used to safeguard the lives of many people. This means that if these systems were to fail they could lead to devastating consequences. Here are some examples of where software systems are used heavily and could be very dangerous if they were to fail - aviation, hospitals, space exploration, nuclear power stations and communications. I will be looking at some examples of actual software failure in these fields to explain the reasons why systems fail.2.0 Reasons for Systems FailureIf software systems failure can be so dangerous why can they not be completely eliminated? According to Parnas, "The main reason is that software can never be guaranteed to be 100% reliable.
The term incident refer to the combine set of occurrences of both incident and near misses.(Otong,2001) it refer to unwanted event involving safety incident with environment impact. Incident is not one person failure it may involve the system
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From a young age Galileo was both bothered and motivated by the lack of scientific rule and emphasis on church rule. Galileo’s approach to learning was very admirable. Instead of sticking to his course of study, he learned by investigating his everyday activities. By learning to inquire further about what interested him, he made e...
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Galileo is one of the greatest scientists in the world, especially at that moment. At that
The primary cause is of airplane accidents does at some stage contain an element of a person being unable to discharge his duties correctly and in an accurate manner. More than 53% accidents are the result of ignorance or faults by the pilot during flight. Other staff is responsible for about 8% accidents. The most obvious errors by pilot are made during the take off or landing on the runway. Additionally errors can occur during the maintenance of the airplane outside the plane, whereby a lack of thorough inspection and oversight can lead to complication during mid-flight. Fueling and loading of the plane also sometimes create problems (Shapiro, 2001).
In the past, the term "accident" was often used when referring to an unplanned, unwanted event. To many "accident" suggests an event that was random, and could not have been prevented. Since nearly all work site fatalities, injuries, and illnesses are preventable, OSHA suggests using the term "incident" investigation. An incident usually refers to an unexpected event that did not cause injury or damage this time but had the potential. "Near miss" or "dangerous occurrence" are also terms for an event that could have caused harm but did not.