Error management analysis

In the second case study, variation tree analysis and the events and causal factors chart/root cause analysis method are applied to an incident in a resin plant. This case study illustrates the application of retrospective analysis methods to identify the imderlying causes of an incident and to prescribe remedial actions. This approach is one of the recommended strategies in the overall error management framework described in Chapter 8. 

Table II demonstrates how NPV would be calculated for a hypothetical LIMS, purchased as a package with negligible site preparation and with installation costs included in the purchase. It is to be acquired for a service laboratory primarily supporting R D activities but with some minimal process monitoring responsibilities. The IRR for this project could be found by trial and error determination of the yearly discount rate which results in a zero NPV. A succinct discussion of these financial management analysis tools can be found in two works by Weston and Brigham. The first (9) presents theoretical and detailed analytical expositions the second OO) is a more practical, applications oriented presentation.

There is some uncertainty in all data, and model building must take this error into account. The first step in error management is error detection, error reduction, and error quantification. There are three types of error systematic error, random error, and blunders. Improved experimental protocol can reduce all these, but designing progressively better experiments eventually leads to diminishing returns so that at some point it is necessary to use some kind of error analysis to manage the uncertainty in the variable being quantified. 

As the objective of the study was to explore and document the error management strategies used by expert pilots, in order to inform the syllabus and ciuriculum structure of an error management training package, the analysis of interview data was undertaken with explicit reference to the interpretive research design. Accordingly, the study did not seek to test pre-defined hypotheses or adopt any detailed quantitative analysis of data. 

This study has provided a detailed account of error management, through the analysis of experts imderstanding of error avoidance, detechon and resolution. From the results of this study, it is evident that elements of error management share much in conunon with our current understanding of Crew Resource Management (CRM). 

As mentioned above in relation to the pre-emptive approaches to human error management, the additional analysis required is not fundamentally different from that which is often already undertaken. All that is necessary is a framework which ensures that the factors which predispose human error are investigated systematically and comprehensively. Once again, the process is more important than the procedure. 

From a human reliability perspective, a number of interesting points arise from this example. A simple calculation shows that the frequency of a major release (3.2 x lO"" per year) is dominated by human errors. The major contribution to this frequency is the frequency of a spill during truck unloading (3 X10" per year). An examination of the fault tree for this event shows that this frequency is dominated by event B15 Insufficient volume in tank to imload truck, and B16 Failure of, or ignoring LIA-1. Of these events, B15 could be due to a prior human error, and B16 would be a combination of instrument failure and human error. (Note however, that we are not necessarily assigning the causes of the errors solely to the operator. The role of management influences on error will be discussed later.) Apart from the dominant sequence discussed above, human-caused failures are likely to occur throughout the fault tree. It is usually the case that human error dominates a risk assessment, if it is properly considered in the analysis. This is illustrated in Bellamy et al. (1986) with an example from the analysis of an offshore lifeboat system. 

Assume that the system described below exists in a process unit recently purchased by your company. As the manager, the safety of this unit is now your responsibility. You are concerned because your process hazard analysis team identified the potential for an operator error to result in a rupture of the propane condenser. You have commissioned a human reliability analysis (HRA) to estimate the likelihood of the condenser rupturing as the result of such an error and to identify ways to reduce the expected frequency of such ruptures... 

Pennycook, W. A., Embrey, D. E. (1993). An Operating Approach to Error Analysis. In Proceedings of the First Biennial Canadian Conference on Process Safety and Loss Management. Edmonton, 24th April. Waterloo, Ontario, Canada Institute for Risk Research, University of Waterloo. 

Part—I has three chapters that exclusively deal with General Aspects of pharmaceutical analysis. Chapter 1 focuses on the pharmaceutical chemicals and their respective purity and management. Critical information with regard to description of the finished product, sampling procedures, bioavailability, identification tests, physical constants and miscellaneous characteristics, such as ash values, loss on drying, clarity and color of solution, specific tests, limit tests of metallic and non-metallic impurities, limits of moisture content, volatile and non-volatile matter and lastly residue on ignition have also been dealt with. Each section provides adequate procedural details supported by ample typical examples from the Official Compendia. Chapter 2 embraces the theory and technique of quantitative analysis with specific emphasis on volumetric analysis, volumetric apparatus, their specifications, standardization and utility. It also includes biomedical analytical chemistry, colorimetric assays, theory and assay of biochemicals, such as urea, bilirubin, cholesterol and enzymatic assays, such as alkaline phosphatase, lactate dehydrogenase, salient features of radioimmunoassay and automated methods of chemical analysis. Chapter 3 provides special emphasis on errors in pharmaceutical analysis and their statistical validation. The first aspect is related to errors in pharmaceutical analysis and embodies classification of errors, accuracy, precision and makes... 

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