Abstract
Various safety models have been developed for use in understanding aspects of safety. These models include the Systems-Theoretic Accident Model and Processes (STAMP) model, Construction Accident Causation model, and Accident Causation Management model. Each model focuses on a specific aspect of the safety process. The STAMP model focus on the interactions between system components while Accident Causation Management model focuses on the source of human errors. On the other hand, Construction Accident Causation model focus on the predictability of incidence occurrence. None of this can be used to understand and address all safety concerns. This essay will begin by a comparison and contrast of CAC model with the STAMP model. This will be followed by identification of STAMP model features which are also inherent in Accident Causation Management System. Finally, there will be a discussion of the benefits and limitations of the three models when used in OSHA to address safety concerns.
Compare and contrast the Construction Accident Causation Model and the STAMP model.
The STAMP model is based on certain principles and is applicable for sociotechnical systems which are being developed in the modern era. In the STAMP model, the explanation of accident has been expanded beyond just failure events to include systematic or indirect causal mechanisms and component interaction accidents. In the STAMP model, the problem to be handled is the control aspect where the objective is to control the system behaviour by enforcing constraints in the system during the design and operation. In the STAMP model approach, the understanding of why an accident occurred requires one to find out why the controls were ineffective. According to Leveson (2011), the STAMP accident model is based on the three basic constructs: hierarchical safety control structures, safety constraints as well as process models. Unlike the STAMP model, Construction Accident Causation model operates on a different principle from STAMP. According to Mitropoulos, Abdelhamid, and Howell (2005) pointed out that the development of strategies for effective prevention of accidents depends on a good understanding and addressing of the causal factors which causes them. In the STAMP model, the focus is on the control aspect. In the Construction Accident Causation model, the emphasis is on causal factors or chain of events leading to an accident. Construction Accident Causation Model focuses on the attributes of the production system which are likely to cause accidents and influence human behaviours. The model assumes that by reducing human errors, it is possible to reduce accidents. In the STAMP model, improvements in the control system behaviour are believed to improve safety. The Construction Accident Causation model is based on the descriptive model of human behaviour while the STAMP model is based on system behaviour. The two models, however, exhibit some similarities. For example, both are focused on accident prevention strategies. Both the STAMP model and the Construction Accident Causation Model employ a systematic procedure to reducing accidents.
References
Leveson, N.G. (2011). Engineering a Safer World: Systems Thinking Applied to Safety. Massachusetts: MIT Press.
Mitropoulos, P., Abdelhamid, T. S., & Howell, G. A. (2005). Systems model of construction accident causation. Journal of Construction Engineering and Management, 131(7), 816-825.
Question (b)
Identify STAMP model features inherent within the Accident Causation Management System.
According to Kwon, Yoon, and Moon (2006), Accident Causation Management (ACM) model views incidences as a product of individual differences. An incident is described as an abnormal effect of either management or technological system. This definition is consistent with that used in the STAMP model. A comparison of the STAMP model and the Accident Causation Management System show that there are features which are common to both. In both models, there is an element of control. However, in STAMP model, the control aspect is on systems while in the ACM model, the control aspect is a human. Controls are put in place by the imposition of safety constraints. Accidents are said to happen when there are inadequate controls. To bring a better understand of the models, case studies are used in both models. In the ACM, there is an attempt to investigate and address the cause of the problem. There is also a feature of causation. Addressing the problem in both models requires an investigation of the causation factors. The human factor is a feature ACM, and it also appears in STAMP. In both models, one of the sources of the accident is human errors during operation. Art from human errors, AMS also recognise other causes of accidents including technical and uncontrollable physical circumstances. However, the contribution of technical and uncontrollable physical circumstances in ACM is regarded low. In both cases, there are also control structures and process models. In the ACM model, the control structures are achieved by minimising human errors by training and increasing employee commitment. In order achieve an effective level of control in ACM model, there is a need to construct process models. Process models are also found in STAMP model. However, in ACM the process model involve a chain of events leading to an accident or a loss. Finally, there is a feature of analysis applicable to both models. However, while ACM model is more focused on human factor analysis, STAMP model is more focused on systems analysis.
References
Kwon, H., Yoon, H., & Moon, I. (2006). Industrial applications of accident causation management system. Chemical Engineering Communications, 193(8), 1024-1037.
Leveson, N.G. (2011). Engineering a Safer World: Systems Thinking Applied to Safety. Massachusetts: MIT Press.
Question (c)
Describe the benefits and limitations of the STAMP model, the Construction Accident Causation Model, and the Accident Causation Management System as each attempt to assist OSHA in the mission of addressing the aspect of human behaviour within their respective designs.
The STAMP model offers great benefits to addressing an aspect of human behaviour in safety. The modern combination of events leading to accidents is increasingly becoming complex and this contrast with the traditional events where a chain of events caused accidents. Instead of focusing on the human role in an accident, STAMP model attempt to address safety concerns by focusing on the interaction between system components (Leveson, 2011) rather than the contribution of human behaviour. This minimises the burden of expecting human input in addressing complex safety issues which are beyond their control. The human aspect is left with minimum and simple roles to play where behaviour has little chance of contributing to an accident. One of the limitations of this approach is that the control systems, such as the computers, only give an output depending on the input given. They do not think like human beings. If a wrong command is given to the computer, it might result in an unfavourable outcome. The Certain human behaviour might also create events which eventually leads to a wrong system response. STAMP model fails to integrate system control with human behaviour.
Accident Causation Management System attempts to address safety issues as per the statistics released about the causes of accidents which show that human error is responsible for most accidents (Kwon, Yoon, and Moon, 2006). Previous investigations suggest that up to 90% of accidents reported take place in industrial facilities. If 90% of the accidents occur in industrial facilities, the use of the model is likely to cause a huge reduction in the cases of reported accidents in industrial settings. This model will largely contribute to OSHA’s mission to addressing safety concerns in the workplace. The limitation of this model is that it is favourable for industrial complexes with many workforces. This approach is limited to situations where it is possible to describe clearly a chain of events leading to an accident. Certain industries like power plants and transport equipment rely on minimum human input in safety matters. This approach will not work in such situations because most of the safety concerns have a lot to do with system components.
The Construction Accident Causation model advanced by Mitropoulos, Abdelhamid, and Howell (2005) attempts to address safety concerns from a systems point of view. It focuses on how characteristics of production systems which has been associated with hazardous incidences.it also analyse conditions which trigger hazards. This approach is a departure from both the STAMP and the ACM model. The model recognises the role played by predictability in minimising hazardous situations. As a result, the model helps in putting place mechanisms to ensure reliable production planning to minimise task unpredictability. The model also helps OSHA in ensuring that improved management of error with the potential of increasing the ability of workers in avoidance, trapping, and mitigation of errors (Mitropoulos, Abdelhamid, and Howell, 2005). This model, however, fails to address issues to do with system interactions which are more complex. It deals with the general behaviour of the whole systems and not the interactions among the systems. It attempts to offer solutions to problems caused by a chain of events in systems. The model also fails to recognise the role of human behaviour in triggering hazardous incidences. By just helping to predict the frequency of accidents, the model cannot be employed to solve a problem where even a single occurrence of the incident is too devastating to correct. For example, a nuclear power plant explosion and aircraft engine malfunction leading to crash.
References
Kwon, H., Yoon, H., & Moon, I. (2006). Industrial applications of accident causation management system. Chemical Engineering Communications, 193(8), 1024-1037.
Leveson, N.G. (2011). Engineering a Safer World: Systems Thinking Applied to Safety. Massachusetts: MIT Press.
Mitropoulos, P., Abdelhamid, T. S., & Howell, G. A. (2005). Systems model of construction accident causation. Journal of Construction Engineering and Management, 131(7), 816-825.
