NOTE: Free essay sample provided on this page should be used for references or sample purposes only. The sample essay is available to anyone, so any direct quoting without mentioning the source will be considered plagiarism by schools, colleges and universities that use plagiarism detection software. To get a completely brand-new, plagiarism-free essay, please use our essay writing service.
One click instant price quote
... italy time available 0. 3 h Extreme stress, rarely performed task 1. 0 Worse still, these out of operational tolerance scenarios have been purposely encountered in disasters such as Chernobyl. Reactor tests were undertaken leading the reactor to be run at unsafely low reactor levels with operators possessing only a limited understanding of the system they were controlling. This was coupled with a task that made dangerous violations inevitable. Clearly, the governing body should be required to assess the trade off between the benefits of increased automation to the safety aspects of supervisory operators with a low cognitive appreciation of the detailed process being automated. This introduces a whole new topic relevant to corporate governance strategies in operation, commonly referred to as Ironies of Automation.
This topic is discussed later. 2. 4 Systems becoming more Opaque With catastrophes becoming increasingly unacceptable technology is applied to high-risk complex systems (such as chemical and nuclear sites) in the form of Automatic Safety Devices (ASDs) to protect against all known breakdown scenarios. These types of developments have made these systems more complex, tightly coupled and highly defended. As a consequence the systems are increasingly opaque to the people who manage, maintain and operate them. The opacity has two facets: not knowing what is happening and not understanding what the system can do. Analysis of major accidents reveals that the safety of the system was eroded by latent errors. Humans operate best in dynamic environments where slips and mistakes are immediately visible - such as driving.
Complex systems can require several errors or events to coincide before a visible response is communicated to the operator, permitting this build up and cohesion of latent errors. With respect to governance of such systems, design should concentrate on decreasing the duration of such errors, rather than reducing their frequency, in the design and development stages. I am not suggesting complexity of high-risk systems is unnecessary; it clearly has benefits in the ASDs and such in improving operational safety and efficiency. As seen though disasters still happen despite all these, hence there is a need for the governance to improve the humans role and knowledge of operating such complex systems. 3.
Chernobyl Disaster On April 26, 1986, at 1: 23 AM Moscow time a disaster struck the region of Chernobyl in Northern Ukraine. The disaster was the destruction of the # 4 RBMK- 1000 nuclear reactor, due to a nuclear meltdown. The disaster destroyed the reactor and sent a cloud of radioactive dust one mile into the air. Radioactive dust was delivered to surrounding countries, and the world, raising levels of radioactivity worldwide. A relevant and appropriate quote was A nuclear disaster anywhere is a nuclear disaster everywhere. The consequences of this disaster were/ are enormous and too detailed for listing here.
More relevant is determining the primary causes to enable possible governance strategies for future prevention to be discussed later in the document. The test was to undertake experiments on the reactor that meant running at unacceptably and unsteady power levels. This was driven by initiatives to save money but also by curiosity of the operators. Authority to proceed with the tests was given to station staff without the formal approval of the Safety Technical Group and other similar Russian plants had refused such tests on safety grounds. The fact the tests were authorised at all demonstrate top-level institutional and managerial errors combined with a general lack of safety culture in the Russian Government. The following couple of events demonstrate this further: h At 1400 25 April as part of the test plan the ECCS (Emergency Core Cooling System) was disconnected from the primary circuit, stripping the reactor of one of its major defences.
This should not have been tolerated and represents another managerial failure. h At 1405 the Kiev controller requested Unit 4 to continue supplying to the grid, but the ECCS was not reconnected. Although this did not contribute directly to the subsequent disaster, it was indicative of the lax attitude of operators toward safety procedures. Subsequent 9 hours of operating at around 50 percent full power increased xenon poisoning, making plant more difficult to control at low power.
Here lies both design failure through instability and managerial failure in permitting a low safety culture to develop amongst operators. These two events are indicative of how poor governance of the nuclear plant allowed safety standards and operator knowledge to slide with devastating consequences. Later sections will discuss governance strategies to combat the system failures demonstrated above. Automation of such high-risk sites is necessary for safety but a knock on effect is a lack of appreciation and knowledge in the operator of the technical operation. Although a lesser issue in the cause of Chernobyl, a significant topic in the governance of such plants that is discussed in the following section. 4. Ironies of Automation 4. 1 Definition of Ironies Whilst on the topic of human-system interaction it is appropriate to consider this topic, expressed well by Lisanne BainBridge (1987) of University College London.
It concentrates on the difficulties that lie at the heart of the relationship between humans and machines in advanced technical installations. This is an important issue for the governance of organisations and its implications cover both design and operation of facilities. As organisations strive to be as efficient, reliable and safe as possible, system designers see the human operators as inefficient and unreliable desiring to supplant them with automated devices. There are two ironies here: h The first is that designers errors make a significant contribution to accidents and events. h The second is where designers seeking to eliminate human error still leave the operator to do the tasks the designer cannot think how to automate. This means after automation there are two categories of tasks to be undertaken by the human operator.
He/ she is firstly required to monitor the automated system. If the system state drifts outside of tolerance operation the requirement is to take over and stabilise the process using manual control skills, and diagnose the fault as a basis for shutdown or recovery using cognitive skills. However, it is a well-known fact that humans in monitoring roles cannot maintain effective vigilance for more than a short period of time and are subsequently ill suited to detecting rare, abnormal events. The second operator task is to take over manual control when automation fails, but little practise of manual control is experienced leading to de-skilled operators over time V ironically worse in more reliable plants.
The irony here being when something goes wrong operators need to be more skilled to effectively deal with the incident, not less skilled as transpires from this scenario. The underlining issue here is that automated systems were not designed with human interfacing as a priority. To reduce the probability of serious incidents arising due to the above points, steps can be taken by organisations to reduce these probabilities through consideration in the design and operation (monitoring) stages. Some of these are outlined in the following section. 4. 2 Approaches to Solutions 4. 2. 1. Monitoring In situations where low probability events need to be quickly noticed by operators designs should incorporate artificial assistance such as audio and visual alarms.
In designs with a large number of loops in the process some form of alarm analysis is required to allow the operator to focus on the correct part of the plant. Much care needs to be taken in the design of large alarm systems as a proliferation of flashing lights can hinder rather than aid the operator. The governance of such alerting systems should be a major consideration in the design of complex high-risk systems such as the control and alerting systems for nuclear and chemical plants. The concept of using Multi Function Displays (MFDs) on VDUs seems appropriate to me.
This permits the operator to access the data he requires from the same terminal rather than using multi terminals. The analogy I recall is the Eurofighter cockpit that uses three MFDs as the primary displays. The information desired by the user is easily accessible and any warnings outside of these displays will be flagged to the pilots attention so as n...
Free research essays on topics related to: high risk, operator, complex systems, operators, section 4
Research essay sample on Complex Systems High Risk
