Safety Reliability and Risk Management, Human Error as the Dominant Cause of Failure - Coursework Example

Safety Reliability and Risk management Name: Lecturer: Course: Date: Introduction The roles of human errors in causing accidents have been widely reviewed by industrial psychologists to determine possible measures to manage them. It is estimated that human error is a significant contributing factor to some 90 percent of major industrial accidents (Gordon 1996). This essay argues that although uncontrollable physical circumstances and technical errors contribute significantly to accident causation, human error is the dominant cause of failure. This article examines types of Human Error within industry and critically analyses how they have been involved in past industrial accidents. Possible measures of reducing human error in the industry are also discussed. In the second part, a safety problem of a washing machine is analysed using a Fishbone diagram to determine the root cause of the safety problem. Part 1 Types of Human Errors in Industrial accidents Human error implies that an actor has performed an intended action as a result causing undesirable outcome. The action depicts a deviation from expectations or a set of rules. Put differently, human error describes an incorrect decision, improper lack of action or an action that is unacceptably performed (Shappel & Wiegmann 2000). There are various types of human errors, mostly discussed from the perspective of different proposed theories. Gordon (1996) cited industrial psychologists Rasmussen (1993) and Reason (1991) in discussing that attempts to understand and defeat human error can minimise its impacts. According to Rasmussen’s (1992) the theory of human performance, human errors can be categorized into skill-based errors such as lapses and slips, rule-based errors and knowledge-based errors. Reason (1991) described human errors using Rasmussen’s theory. According to Reason (1991), preoccupation or distraction can cause skill-based errors leading to lapses or slips that cause an unintended action to occur. In knowledge-based or rule-based errors, failures in problem solving may occur once an employee applies an incorrect rule. The types of errors based on Rasmussen’s theory are intended to define the errors in high-risk industries. Though they appear to provide an ideal model that can be used in describing typical industrial accidents, this essay argues that the error types described by Rasmussen (1993) are somewhat complex and can be difficult to apply in industrial situations without extensive training (Gordon 1996). Therefore, a simpler approach suggest by Gordon (1996) is adopted. The researcher proposed that human errors can be categorized into six types, namely action errors, retrieval errors, checking errors, diagnostic errors, transmission errors and decision errors. Decision errors occur in situations where although all the preventive measures are considered, wrong decisions are made (Gordon 1996). An example of a major industrial accident caused by a decision error was the Flixborough chemical plant disaster that happened in 1974 in the UK, resulting to the death of 28 workers. Studies established that in a bid to cut costs and use of electricity given the 1974 fuel crisis, Nypro UK, which owned the plant, curtailed the regular stirring of tanks to prevent the build-up of water condensation in tanks resulting to incidences where water flashed to steam because of over pressure. As a result, there was an explosion causing widespread property damage within a 6-mile radius. Design errors was also a direct cause, as failure of the badly designed 20-inch bypass pipe between reactor 4 and 6 caused massive release of inflammable vapour that ignited causing vapour explosion (Whittingham 2004). Action errors describe human errors characterized by failure to take an action or taking a wrong action. In this case, although an action is taken, it is applied to the wrong object. At Bhopal, a leak discovered from a storage tank was assumed by a supervisor to be a mere water leak. No action was taken. In actuality, an earlier cleaning exercise had left water inside the tank by mistake causing exothermic reaction (Brougton 2005). The operators pumped Methyl-isocyanate (MIC) into the leaking tank, which increased pressure inside the tank hence bursting a valve. The MIC leaked and vapoured into toxic cloud. At least 3,800 people were killed from exposure to the vapour (Peters & Peters 2006). Checking errors comprise of human errors where checking or monitoring systems is omitted. Additionally, a wrong action may be taken or the right check may be applied to a wrong object. Chernobyl nuclear disaster of 1986 was a result of checking error (Rubin 1987). During the testing by a group of engineers to check whether the long stable power could be maintained in case of power failure that needed power to be switched over to a diesel generator, they instead made inferences on how non-operational the reactor could be. A result, there was a time lag between the switchover the diesel system. This rendered the reactor unsafe to manage. An explosion occurred causing property damage and killing 35 people (Meshkati 1991). Retrieval errors consist of errors where required information is not made available in critical decision making. Additionally, wrong information may be retrieved. The Three Mile Island (TMI) nuclear disaster of 1979 resulted due to misinformation. A cooling circuit pump malfunctioned resulting to heating of a coolant of the reactor and rise in internal pressure. Operators in the control room observed that “close” command signal was sent to release the valve. However, nothing was displayed on the actual position of the valve. Information was sent to operators that indicated the coolant system had too much pressure. They shut down the water pumps to release pressure. However, radioactive steam had build up causing explosion. Thousands of cases of cancer resulted (Rubin 1987). Transmission errors occur when information that has to be conveyed to someone else is sent to a wrong person or place. On the other hand, diagnostic errors take place when unusual events happen, leading the actual situation to be misinterpreted. Piper Alpha accident that happened in 1988 was a result of transmission errors and diagnostic errors resulting to an explosion that killed 162 men (Pate-Cornell 1993). When engineers checked the condensate pump of the processing area, they noted that it needed safety pressure valve examined. Diagnosis showed it could still be safe to operate. They started working on the valve, but since they could not finish by 6pm, they decided to leave the rest of the work for the next day and sealed the tube with a plate. The management allowed them to leave. They however failed to convey to the evening staff that vital parts of the machines had been removed. Gas escaped through the holes left in the valve resulting to explosions (Pate-Cornell 1993). Possible measures of reducing human error in industry Organizations should promote learning from past accidents as observed by Pate-Cornell (1993). Gordon (1998) suggested four ways organizations could use to learn from past experiences. These include description of old accidents in safety bulletins or discussing them in meetings. Second, maintaining standards and codes of practice that has notes on accidents and related recommendations. A book that contains reports of accidents should be made a compulsory reading during orientation of new workers. Fourth, retrieval and storage of accident information should be used maximally. Accident reporting should also be encouraged creating a group climate that encourages employees to get along each other encourages communication, hence reducing transmission errors (Rooney, Vanden & Lorenzon 2002; Kohn, Corrigan & Donaldson 2000). The management should set up standards of safety leadership and work practice to prevent decision errors. Additionally, company standards and system procedures can prevent action errors and transmission errors (Kjestveit et al 2003). Effective supervision of the plant and workers may prevent any latency errors (Gordon 1998). Part 2 Safety problem relating to a Washing Machine Using Root Cases Analysis, a safety problem with a washing machine is addressed in order to depict the causes and the key causes of the safety problem. This is essential as it helps correct and eliminate causes as well as prevent the problem from returning. Using a fishbone diagram, focus on a range of possibilities becomes easier in determining the root cause of the problem (Jayswal et al 2011). Problem Description of the Washing Machine A washing machine (serial #54390-63534-9383) is 4 weeks old. On doing the fourth load of clothing, a loud noise occurs and the machine stops working. Fire flickered at the socket as plastic burned, showing the washing machine was a potential fire hazard. Afterwards, the singed socket still works but the washing machine won’t restart. Investigating the problem Since the machine does not work, it has to be established why. Four options are examined. Namely, whether power is off, the machine is unplugged, fuse is blown or fuse is missing. It is established that fuse is faulty. It is determine that the Fuse is blow. The cause of the blown fuse has to be established. It is established that the blown fuse was caused by overheating of the motor. Corrective action for the deficiency would be to replace the fuse. However, the cause of overheated motor is investigated. It is established that overheating of the motor was caused by existence of a damaged shaft. Corrective action would be to replace the shaft. The cause of the damaged shaft is determined. It is established that overheating of the motor occurred due to a damaged shaft. Corrective action will entail replacing the shaft. The cause of the damaged shaft is destroyed shaft. It is established that an omitted seal resulted to the damage shaft. Corrective action would be to replace the bearing. The cause of the omitted seal is determined. The root cause of the problem (omitted seal) is inadequate instructions Conclusion Although uncontrollable physical circumstances and technical errors contribute significantly to accident causation, human error is the dominant cause of failure. Attempting to understand and defeat human error can reduce industrial accidents. Human errors can be categorized into six types, namely action errors, retrieval errors, checking errors, diagnostic errors, transmission errors and decision errors. Possible measures to prevent human errors include learning from past accidents and maintaining standards and codes of practice to prevent decision, decision and retrieval errors. Others include accident reporting and effective supervision of the plant and workers to prevent any latency errors. References Brougton, E 2005, The Bhopal disaster and its aftermath: a review, Environmental Health: A Global Access Science Source, Vol. 4 No. 6 doi:10.1186/1476-069X-4-6 Gordon, R 1996, The Contribution of Human Factors to Accidents in the Offshore Oil Industry," Reliability Engineering and System Safety, Vol. 61, p.95-108. Jayswal, A, Li, X, Zanwar, Lou, H & Huang, Y 2011, "A sustainability root cause analysis methodology and its application," Computers and Chemical Engineering, Vol. 35, p.2786–2798 Kjestveit, K, Allred, K & Nesvag, S 2003,The concept of human factors - a discussion of risk assessments, RF – Rogaland Research. Kohn, L, Corrigan, J & Donaldson, M 2000, To Err is Human: Building a Safer Health System, National Academy of Sciences, Washington D.C. Meshkati, N 1991, "Human Factors in Large-Scale Technological Systems' Accidents," Industrial Crisis Quarterly, Vol. 5, 131-154 Pate-Cornell, M 1993, "Learning from the Piper Alpha Accident: A Postmortem Analysis of Technical and Organizational Factors," Risk Analysis, Vol. 13, No. 2, p. 215-232 Peters, G & Peters, B 2006, Human Error: Causes and Control, Taylor and Francis, Boca Raton, FL Rasmussen, J 1993, Perspectives on the concept of human error. Invited Keynote Talk given at the Human Performance and Anesthesia Technology. Society for Technology in Anesthesia Conference, New Orleans in February 1993 Reason, J 1991, Human Error, Cambridge University Press, Cambridge Rooney, J, Vanden, L & Lorenzon, D 2002, Reduce Human Error, Quality Progress, viewed 2 March 2014, http://www.capapr.com/docs/reducing%20human%20error%20QP.pdf Rubin, D 1987, “How the News Media Reported on Three Mile Island and Chernobyl,” Journal of Communication, Vol. 37 NO. 3, p.42-51 Shappel, S & Wiegmann, D 2000, The Human Factors Analysis and Classification System–HFACS, Office of Aviation Medicine, Washington, DC Whittingham, R 2004, The Blame Machine: Why Human Error Causes Accidents, Elsevier Butterworth-Heinemann, Burlington Read More