Safety Accident Causation

Sergio Ley Lopez, et al. 2009. From the "track crossover theory" coal mine safety accident causation and prevention. Shan xi Coking Coal Science and Technology, (l) 71-73. 

This model of accident causation is described further in Figure 1.3. This represents the defenses against accidents as a series of shutters (engineered safety systems, safety procedures, emergency training, etc.) When the gaps in these shutters come into coincidence then the results of earlier hardware or human failures will not be recovered and the consequences will occur. Inap-... 

The traditional safety engineering approach to accident causation focuses on the individual rather than the system causes of error. Errors are primarily seen as being due to causes such as lack of motivation to behave safely, lack of discipline or lack of knowledge of what constitutes safe behavior. These are assumed to give rise to "unsafe acts." These unsafe acts, in combination with "unsafe situations" (e.g., imguarded plant, toxic substances) are seen as the major causes of accidents. 

Similar remarks can be made about accident reports, it was observed that the focus of the majority is on the direct safety related deviations in the accident causation path, and almost no attention is given to the indirect safety related deviations. Indirect safety related deviations were mentioned but no attention was given to the fact that these deviations were in the causal path, re-occurring, and often present for a long time prior to the accident. Korvers (Korvers et al., 2002) gave some good examples by showing ten cases in which identical indirect safety related deviations present prior to accidents repeatedly caused similar accidents. 

I, Chapters 2 and 3 deal with the general backgrounds of industrial safety (e,g, models of accident causation and of human behaviour) and with the contributions that near miss reporting could make in understanding and controlling accidents and incidents, Also theoretical criticisms of the near miss reporting efforts are discussed here,... 

The Swiss cheese model of accident causation was originally proposed by British psychologist James T. Reason and has since gained widespread acceptance in many risk-analysis and management fields including process safety. 

Manu, R, Ankrah, N., Proverbs, D. and Suresh, S. (2010) The contribution of construction project features to accident causation and health and safety risk a conceptual model. In C. Egbu (ed.). Proceedings of the 26th Annual ARCOM Conference, pp. 261-9. Association of Researchers in Construction Management, Leeds. 

According to the modem accident-causation (G. and B. et al., 2005), from the point of individual behavior-safety control, hazard is embodied unsafe act (behavior) and unsafe condition meanwhile, under certain situation, unsafe act (behavior) can transform and result in unsafe condition. The unsafe act and unsafe condition is the direct cause of accident, deeper analysis comes to the indirect (common) cause, which include three elements inadequate safety knowledge, inadequate safety awareness, and inadequate safety habit. 

Fu Gui et al. 2013. Behavior-based Accident Causation The 2-4 Model and Its Safety Implications in Coal Mines. Journal of China Coal Society. 38 (7) 1123 -1129. 

The STAMP (Systems-Theoretic Accident Model and Process) model of accident causation is built on these three basic concepts—safety constraints, a hierarchical safety control structure, and process models—along with basic systems theory concepts. All the pieces for a new causation model have been presented. It is now simply a matter of putting them together. 

This book suggests a new approach to engineering for safety that changes the focus from prevent failures to enforce behavioral safety constraints, from reliability to control. The approach is constructed on an extended model of accident causation that includes more than the traditional models, adding those factors that are increasingly causing accidents today. It allows us to deal with much more complex systems. What is surprising is that the techniques and tools described in part 111 that are built on STAMP and have been applied in practice on extremely complex systems have been easier to use and much more effective than the old ones. 

The current status of behavioral safety is reviewed. Comments are made on the changes in approaches that have taken place how the message has changed somewhat from emphasis on worker behavior to management systems the interface of the worker with the workplace environment and performance improvement. Also, the behavioral aspect of accident causation and where behavioral safety fits in an overall, effective safety management system are put in prospective. 

A great many safety practitioners have adopted the premises on which the 88 10 2 ratios are based, and they apply them to this day. Of all the Heinrich concepts, his thoughts pertaining to accident causation, expressed as the 88 10 2 ratios, have had the greatest impact on the practice of safety and have done the most harm. Why harm Because when basing safety efforts on the premise that man failure causes the most accidents, the preventive efforts are directed at the worker rather than on the operating system in which the work is done. 

Heinrich recognized that other studies on accident causation identified both unsafe acts and unsafe conditions as causal factors with almost equal frequency. Those studies produced results different from his 88 10 2 ratios, and Heinrich commented on those differences. For example, he cited the National Safety Council as a resource on such studies (Citation 22). 

In the eighth edition of the National Safety Council s Accident Prevention Manual for Industrial Operations Administration and Programs, these comments were made about studies of accident causation. 

While psychology has a place in safety management, the emphasis Heinrich gave to it as being a fundamental of great importance in accident causation was disproportionate, and that overemphasis influenced his work considerably, and that of many safety practitioners. 

At the Safety Technology 2000 symposium held by the American Society of Safety Engineers in June of 1995, many of the papers presented made specific reference to or alluded to an accident causation concept. From a review of those papers, it was obvious that the beliefs of safety professionals about concepts of hazards-related incident causation are far from consensus. These are the extremes in the variations expressed on incident causation in those papers ... 

Use of Heinrich s ideas has led to oversimplification and has encouraged identifying a single causal factor for incidents focusing on employee error. Johnson makes these statements about accident causation in MORT Safety Assurance Systems ... 

DeJoy, David M. Toward a Comprehensive Human Factors Model of Workplace Accident Causation. Professional Safety, May 1990. 

This is Heinrich s accident causation theory and is operationalized in the following 10 statements known as the "Axioms of Industrial Safety" [2,3,20] ... 

Emerging concepts of system analysis, accident causation, human factors, error reduction, and measurement of safety performance strongly suggest the practicality of developing a higher order of control over hazards (than currently exists). 

The study of patient safety is the study of complexity. The study of complexity invites us to understand key concepts that can be applied to patient safety. Basic concepts from the fleld of patient safety are sharp and blunt end active and latent failure the Swiss Cheese Model of Accident Causation slips, lapses, and mistakes and hindsight bias and the fundamental attribution error. Key concepts from organizational analysis, such as normalization of deviance, diffusion of responsibility, tightly coupled work processes, and sensemaking, introduce practical lessons from high-reliability organizations. Application of specific lessons to health care are explored in Chapter Five. 

The Swiss Cheese Model of Accident Causation is a prerequisite for understanding the dynamics of the emerging risk and organizational defenses that are necessary to improve safety. Figure 4.2 illustrates the model, using its metaphor, a wedge of Swiss cheese. The model was described in detail in Chapter Three here, a metaphorical exploration of the model amplifies its implications for accepting leadership responsibility. 

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