Vulnerability defined

In contrast, most equipment can safely tolerate higher degrees of heat density than those defined for personnel. However, if anything vulnerable to overheating problems is involved, such as low melting point construction materials (e.g., aluminum or plastic), heat-sensitive streams, flammable vapor spaces, or electrical equipment, then the effect of radiant heat on them may need to be evaluated. When this evaluation is required, the necessary heat balance is performed to determine the resulting surface temperature, for comparison with acceptable temperatures for the equipment. 

The analysis of accidents and disasters in real systems makes it clear that it is not sufficient to consider error and its effects purely from the perspective of individual human failures. Major accidents are almost always the result of multiple errors or combinations of single errors with preexisting vulnerable conditions (Wagenaar et al., 1990). Another perspective from which to define errors is in terms of when in the system life cycle they occur. In the following discussion of the definitions of human error, the initial focus will be from the engineering and the accident analysis perspective. More detailed consideration of the definitions of error will be deferred to later sections in this chapter where the various error models will be described in detail (see Sections 5 and 6). 

Exposure assessment is one of the most important steps in risk assessment. It is the process that predicts or estimates the amount of the substance under study that reaches the human body. To assess the exposure, it is necessary to define in detail the exposure pathway, the route of exposure, the concentration of the pollutant in the particular media, the contact rate, the frequency of exposure, and the population exposed (age, gender, and vulnerable population, among others). A general equation (Eq. 1) to determine the exposure dose is as follows ... 

A one-dimensional SOM is less effective at filling the space defined by input data that cover a two-dimensional space (Figure 3.22) and is rather vulnerable to entanglement, where the ribbon of nodes crosses itself. It does, however, make a reasonable attempt to cover the sample dataset. 

A review of the literature on chemical-induced immunosuppression in rats and mice, exposed during the pre- and/or postnatal period, was compared to exposure of adults. Five known immunosuppressants (i.e., TCDD, TBTO, DES, Pb, and diazepam) were reviewed. The data revealed that the developing immune system was more sensitive to chemical exposure than the mature immune system. Based on these evaluations, the authors concluded that it was reasonable to assume that testing only in adults would not provide a sufficient level of sensitivity to define immunotoxicity in the neonate 132. In summary, this chapter provides compelling evidence that the developing, compared to the mature, immune system is more vulnerable to perturbation. 

Corrective action, broadly defined, includes not only the process of addressing identified deficiencies, weaknesses, or vulnerabilities, but also the processes for corrective action planning and follow-up. The corrective action process can be summarized as follows. 

Many metals are fairly easily oxidized. The atmosphere contains a powerful oxidizing agent oxygen. Because metals are constantly in contact with oxygen, they are vulnerable to corrosion. In fact, the term corrosion is sometimes defined as the oxidation of metals exposed to the environment. In North America, about 20% to 25% of iron and steel production is used to replace objects that have been damaged or destroyed by corrosion. However, not all corrosion is harmful. For example, the green layer formed by the corrosion of a copper roof is considered attractive by many people. 

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