Lack of knowledge

Safe operation for many years does not prove that a reaction will not run away. Unknown to the operators, the plant may be close to the conditions under which it becomes unstable, and a slight change in pressure, temperature, or concentration, too small to cause concern, may take it over the brink. The operators are blind men walking along the edge of a precipice, as the following incidents illustrate. 

The control of the reaction was based on the assumption that stopping the flow of chlorine would stop all reaction this was true on the pilot unit but not on the full-scale plant. On the pilot unit, there was no stirrer, as the incoming chlorine gave sufficient mixing. When chlorine addition stopped, mixing also stopped and so did the reaction. On the full-scale plant, a stiirer was necessary, and this continued in operation after chlorine addition stopped. In addition, on the pilot unit the cooling was sufficient to hide any continuing reaction that did occur. 

Stirring was attempted during the ARC tests, but the iron powder interfered with the mechanically coupled stirrer [4], 

A reaction was believed to be thermally neutral, as no rise in temperature was observed in the laboratory. No cooling was provided on the pilot plant, and the first batch developed a runaway. Fortunately the relief valve was able to handle it. Subsequent research showed that the reaction developed 2 watts/kg/°C. Laboratory glassware has a heat loss of 3-6 watts/kg/°C, so no rise in temperature occurred. On the 2.5-m3 pilot plant reactor, the heat loss w as only 0.5 watt/kg/°C [21]. Reference 22 lists heat losses and cooling rates for vessels of various sizes. 

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Supervisors are responsible to see that every worker is adequate on the job. Physically, mentally, and emotionally inadequate workers are accident prone. Personal hazards are lack of knowledge, conflict of motives, physical, and mental factors. 

Lithography. Of the principal printing processes, Hthography is by far the most widely used. But in spite of usage and the numerous studies (60) to which Hthography has been subject over many years, the mechanism of the process is not well understood. This lack of knowledge reflects the complexity of the various interactions of ink, plate, and water that come into play whenever a Hthographic plate mns on press. 

The present author was worried about the lack of knowledge concerning the quality of the kinetic models used in the industry. A model is by definition a small, scaled-down imitation of the real thing. (Men should remember tliis when their mothers-in-law call them model husbands.) In the industry all we require from a kinetic model is that it describe the chemical rate adequately by using traditional mathematical forms (Airhenius law, power law expressions and combinations of these) within the limits of its applications. Neither should it rudely violate the known laws of science. 

The immediate cause of the explosion was an operator forgetting to open a valve. It was not due to lack of knowledge, training, or instructions but was another of those slips that even well-trained, well-motivated, capable people make from time to time. 

A major reason for the neglect of human error in the CPI is simply a lack of knowledge of its significance for safety, reliability, and quality. It is also not generally appreciated that methodologies are available for addressing error in a systematic, scientific manner. This book is aimed at rectifying this lack of awareness. 

This section is concerned with errors that are often classified as "violations," that is, situations where established operating procedures appear to have been deliberately disregarded. Such violations sometimes arise because the prescribed way of performing the task is extremely difficult or is incompatible with the demands of production. Another cause is lack of knowledge of the... 

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. 

Lack of knowledge of modes of use Changes in the situation do not trigger... 

Example 3.7. Lack of Knowledge of Safety Prerequisites before Carrying out Work on a Pump (Kletz, 1994b)... 

The overall conclusion that can be drawn from a survey of CPI data collection systems is that the better systems do attempt to address the causes of human error. However, because of the lack of knowledge about the factors which influence errors, the causal information that is collected may not be very useful in developing remedial strategies. General information in areas such as severity, work control aspects and the technical details of the incident will be required in all data collection systems. However, in almost all cases a structured process for causal analysis is lacking. Some of the requirements for causal analysis are set out in the following sections. 

Mistakes Errors arising from a correct intentions that lead to incorrect action sequences. Such errors may arise, for example, from lack of knowledge or inappropriate diagnosis. 

Uncertainty on tlie other hand, represents lack of knowledge about factors such as adverse effects or contaminant levels which may be reduced with additional study. Generally, risk assessments carry several categories of uncertainly, and each merits consideration. Measurement micertainty refers to tlie usual eiTor tliat accompanies scientific measurements—standard statistical teclmiques can often be used to express measurement micertainty. A substantial aniomit of uncertainty is often inlierent in enviromiiental sampling, and assessments should address tliese micertainties. There are likewise uncertainties associated with tlie use of scientific models, e.g., dose-response models, and models of environmental fate and transport. Evaluation of model uncertainty would consider tlie scientific basis for the model and available empirical validation. 

The risk assessment steps and the risk characterization are influenced by uncertainty and variability. Variability arise from heterogeneity such as dose-response differences within a population, or differences in contaminant levels in tlie environment. Uncertainty on tlie other lumd, represents lack of knowledge about factors such as adverse effects or contaminant levels. 

Feed characterization relates product yields and qualities to feed quality. Knowing the effects of a feedstock on unit yields, a refiner can purchase the feedstock that maximizes profitability. It is not uncommon for refiners to purchase raw crude oils or FCC feedstocks without knowing their impact on unit operations. This lack of knowledge can be expensive. 

As an example of the way in which these data could be used, the temperatures at which carbides separate from an 18/8 stainless steel are calculated for carbon contents of 01, 0-01, 0 001 and 0-0001 wt /o. These calculations, which of necessity involve several approximations due to our present lack of knowledge, demonstrate the value of the thermodynamic approach to problems involving the precipitation of phases which may have a pronounced effect on the corrosion behaviour of the alloy (see Section 3.3). 

Taxol s journey to the clinic was slow and arduous. Initial difficulties with aqueous solubility and lack of knowledge regarding its mechanism, of action delayed its development until 1979 when, in another seminal paper in the field, S.B.Horwitz and her collaborators disclosed their findings on the interaction of taxol with microtubules.4 Taxol s unique biological action, which includes promotion of microtubule formation and microtubule stabilization, stimulated a renewed interest in taxol as a potential drug candidate. The problem of procuring adequate supplies of taxol became even... 

When not enough is known about the matrix, absorption effects (7.3) cannot be estimated, and comparison of standard and unknown (7.8) may be unreliable. Somewhat less likely consequences of such lack of knowledge are errors due to interfering lines and to shifts in x-rav spectra, which can affect both the analytical-line intensity and the background (8.8). Sometimes a quick examination of all the characteristic lines that can be excited in a sample is helpful in giving useful knowledge about the matrix. 

Most patients, at least in die initial treatment stages, have a lack of knowledge about die drug, its possible... 

D Non compliance with drug regimen related to indifference, lack of knowledge, other factors... 

D Ineffective Health Maintenance related to inability to comprehend drug regimen, lack ot equipment to monitor drug effects, lack of knowledge... 

D Risk for Ineffective Regimen Management related to lack of knowledge of technique of instilling an eye drug... 

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