Human error prevention

Firstly, the situation at RAP will be briefly described, and their main reasons for starting a joint research project for Human Error Prevention with Eindhoven University of Technology. Secondly, the design and implementation aspects of a NMMS, tailor-made for RAP, will be outlined, followed by some preliminary results. Finally, those aspects of further development which have been designed, but not yet (fully) implemented will be discussed,... 

This paper deals with the classification of an error type and the characteristics of human errors by each error type for the test and maintenance failures that have led to implanned reactor trips in Korean nuclear power plants. The classification of hmnan errors was basically performed on the taxonomy of Reason s basic error types (Reason 1990). Characteristics of the test and maintenance errors include the major contributing factors or error modes, and predictivity or identifiabil-ity of a potential erroneous action from the viewpoint of a human error prevention or management. 

ABS Consulting Offers a course titled Human Error Prevention and Mitigation. ... 

HUMAN ERROR PREVENTION—A SIGNIFICANT MODIFICATION IN CONCEPT... 

Needed culture change Risk assessments as the core Prevention through design Human error prevention... 

Chemical Reactivity Evaluation and Application to Process Design Preventing Human Error in Process Safety... 

Monitoring by Electromechanical Instrumentation. According to basic engineering principles, no process can be conducted safely and effectively unless instantaneous information is available about its conditions. AH sterilizers are equipped with gauges, sensors (qv), and timers for the measurement of the various critical process parameters. More and more sterilizers are equipped with computerized control to eliminate the possibiUty of human error. However, electromechanical instmmentation is subject to random breakdowns or drifts from caUbrated settings and requires regular preventive maintenance procedures. 

At one time most accidents were said to be due to human error, and in a sense they all are. If someone—designer, manager, operator, or maintenance worker—had done something differently, the accident would not have occurred. However, to see how managers and supervisors can prevent them, we have to look more closely at what is meant by human error-. 

Applying the information-processing model to each of the operator tasks can provide insights into the potential for human error and also suggest solutions for preventing errors. 

A valuable QRA result is the importance of various components, human errors, and accident scenarios contributing to the total risk. The risk importance values highlight the major sources of risk and give the decision maker a clear target(s) for redesign or other loss prevention efforts. For example, two accident scenarios may contribute 90% of the total risk once you realize that, it is obvious that you should first focus... 

Procedural The same reactor described in Example 3 above, but without the 5 psig high pressure interlock. Instead, the operator is instructed to monitor the reactor pressure and stop the reactant feeds if the pressure exceeds 5 psig. There is a potential for human error, the operator failing to monitor the reactor pressure, or failing to stop the reactant feeds in time to prevent a runaway reaction. 

Human factors, discussed in Section 4.2, enter a fault tree in the same manner as a component failure. The failure of manual actions, that prevent or mitigate an accident, are treated the same as hardware failures. The human error failure probability is conditioned by performance sluiping factors imposed by stress, training and the environment. 

Humans control all chemical and nuclear processes, and to some extent all accidents result from human error, if not directly in the accident then in the process design and in the process inadequate design to prevent human error. Some automatic systems such used in nuclear power reactors because the response time required is too short for human decisions. Even in these, human error can contribute to failure by inhibiting the systems. 

A related concept to inherently safer design is user-friendly design designing equipment so that human error or equipment failure does not have serious effects on safety (and also on output or efficiency). While we try to prevent human errors and equipment failures, only very low failure rates are acceptable when we are handling hazardous materials, and, as this book has shown, it is hard to achieve them. We should, therefore, try to design so that the effects of errors are not serious. The follov,/-ing are some of the ways in which we can accomplish this ... 

Many accidents, particularly on batch plants, have been due to runaway reactions, that is, reactions that get out of control. The reaction becomes so rapid that the cooling system cannot prevent a rapid rise in temperature, and/or the relief valve or rupture disc cannot prevent a rapid rise in pressure, and the reactor ruptures. Examples are described in the chapter on human error (Sections 3.2.1 e and 3.2.8), although the incidents were really due to poor design, which left traps into which someone ultimately fell. 

From the organizational view of accident causation presented in the previous section, it will be apparent that the traditional approach to human error, which assumes that errors are primarily the result of inadequate knowledge or motivation, is inadequate to represent the various levels of causation involved. These contrasting views of error and accident causation have major implications for the way in which human error is assessed and the preventative measures that are adopted. 

A combination of on-the-job and off-the-job methods is usually the best solution in most types of training. The following factors should be examined in order to analyze the role of training in preventing human error. Team training will be considered in the social and organizational factors which follow in other sections. 

In addition to their descriptive fimctions, TA techniques provide a wide variety of information about the task that can be useful for error prediction and prevention. To this extent, there is a considerable overlap between Task Analysis and Human Error Analysis (HEA) techniques described later in this chapter. HEA methods generally take the result of TA as their starting point and examine what aspects of the task can contribute to human error, hr the context of human error reduction in the CPI, a combination of TA and HEA methods will be the most suitable form of analysis. 

The type of data collected on human error and the ways in which these data are used for accident prevention will vary depending upon the model of error and accident causation held by the management of an organization. This model will also influence the culture in the plant and the willingness of personnel to participate in data collection activities. In Chapters 1 and 2 a number of alternative viewpoints or models of human error were described. These models will now be briefly reviewed and their implications for the treatment of human error in the process industry will be discussed. 

This indicates that error management comprises two strategies proactive methods are applied to prevent errors occurring, and reactive strategies are used to learn lessons from incidents that have occurred and to apply these lessons to the development of preventive measures. Both proactive and reactive methods rely on an understanding of the courses of human error based on the theories and perspectives presented in this book. The tools and tech-... 

Geyer, T. A., Bellamy, L. J., Astley, J. A., Hurst, N. W. (1990). Prevent Pipe Failures Due to Human Errors. Chemical Engineering Progress, November. 

Leplat,]., Rasmussen, J. (1984). Analysis of Human Errors in Industrial Incidents and Accidents for Improvements of Work Safety. Accident Analysis and Prevention 16(2), 77-88. 

Grasha, A.F., "Into the Abyss Seven Principles for Identifying the Causes of and Preventing Human Error in Complex Systems," Am.. Health-System Pharm., 57, 554 564 (2000). 

Lees (Loss Prevention in the Process Industries, 2d ed., Butter-worths, London, 1996), BP (Hazards of Trapped Pressure and Vacuum, 2003), and Kletz (What Went Wrong —Case Histories of Process Plant Disaster, Gulf Publishing Company, 1989) include additional case histories providing valuable lessons about how equipment failures and human errors can combine to inflict vacuum damage. 

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