Design process human error factors

Human factors are an extremely important part of inherently safer concepts. Processes should be designed to avoid error traps. Chapter 6 of this book presents a discussion of human factors as related to inherently safer design. 

In addition to these formal studies of human error in the CPI, almost all the major accident investigations in recent years, for example, Texas City, Piper Alpha, Phillips 66, Feyzin, Mexico City, have shown human error as a significant causal factors in design, operations, maintenance or the management of the process. Figures 4.4-1 and 4.4-2 show the effects of human error on nuclear plant operation. 

The application of the science of human factors to eliminating error in all aspects of process design, management, operation, and maintenance is the focus of this work. Human error has been a major cause of almost all of the catastrophic accidents that have occurred in the chemical process industries (CPI). If one adopts the broad view of human error as being the result of a mismatch between human capabilities and process demands, then clearly management s role is critical in the following areas ... 

Measures to reduce human error are often implemented at an existing plant, rather than during the design process. The decision to conduct an evaluation of the factors that can affect error potential at an existing plant may be taken for several reasons. If human errors are giving rise to unacceptable safety, quality or production problems, plant management, with the assistance of the workforce, may wish to carry out a general evaluahon or audit of the plant in order to identify the direct causes of these problems. 

The information gathered from the interviews conducted as part of the human error data collection process is entered on paper forms. In order to facilitate the ease and accuracy of data collection, the forms should be designed using human factors guidelines for written materials (e.g., Wright, 1987 Wright and Barnard, 1975). 

This book was written by Dr. David Embrey of Human Reliability Associates, with the assistance of the CCPS Human Reliability Subcommittee. Section 8.2, Managing Human Error by Design, which deals with the application of human factors principles in the process safety management system, was written by the Human Reliability Subcommittee. 

Throughout the product or service life cycle, deterioration is likely to occur. Components wear out, materials become damaged or lose their effectiveness. In the service realm, human error and inconsistencies contribute to process variation and deterioration. To reduce the impact of these factors on performance, use Design FMEA (Technique 40) to flag areas that are susceptible to wear or failure, and then design your product or service to avoid or withstand deterioration as much as possible. 

AMMP works in two complementary folds Design and manufacturing as well as workplace and maintainers orientations. Consequently, the process is intended to effectively monitor the seen and/or inherent existence of maintenance human errors causal factors... 

Almost aU the major accident investigations in recent years. have shown that human error was a significant causal factor at the level of design, operations, maintenance, or the management process. 

The hardware associated with a BPCS operator action is not covered by the standard. However, its performance should be monitored to ensure that it is sufficient. Formal PFD calculation is typically not required. Human factors should be considered in the design of any critical operator activity. For example, the design of the BPCS operator interface should incorporate human factors engineering (HFE) principals to ensure that the operator responds adequately to an alarm or process indication. However, a detailed human-error analysis is not required for operator actions implemented in the BPCS. Refer to Table B-1 for additional allocation and risk-reduction guidance. 

Accident Risk Factor A dangerous element of a system, event, process, or activity including casual factors such as design or programming deficiency, component malfunction, human error or environment, which can propagate a hazard into an accident if adequate controls are not effectively applied (MIL-STD-1574). 

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