Risk decision making complexity

While the complexity of this collective body of observation and experience may improve the quality of risk decision making, the sheer volume of information creates difficult rhetorical problems when individuals must determine a course of action. If individuals attempt to document events from too many incommensurate viewpoints, they can easily become overwhelmed and overcautious in the face of risk. Individuals who limit their documentation to a single viewpoint may face less anxiety, but they will not have sufficient resources to operate in conditions of profound uncertainty. Complexity can provide decision makers with the fullest account of hazardous environments. But decision makers must have the tools to sort through complexity to isolate and weigh how each individual factor contributes to risk. 

The analysis of a risk—that is, its estimation—leads to the assessment of that risk and the decision-making processes of selecting the appropriate level of risk reduction. In most studies this is an iterative process of risk analysis and risk assessment until the risk is reduced to some specified level. The subjec t of acceptable or tolerable levels of risk that coiild be applied to decision making on risks is a complex subject which will not oe addressed in this section. 

Risk-based decision making and risk-based corrective action arc decision making processes for assessing and responding to a health hazard. The processes take into account effects on human healdi and the enviroiunent, inasmuch as chemical releases vaiy greatly in terms of complexity, physical and chemical characteristics, and in the risk that they may pose. Risk-based corrective action (RBCA) was initially designed by the American Society for Testing and Materials (ASTM) to assess petroleum releases, but tlie process may be tailored for use with any hazard. 

In essence, the earlier components of this overall assessment process are mainly deterministic in character (albeit with some probabilistic elements), whereas the later stages are mainly probabilistic. Not all elements of the process are quantifiable (with any degree of confidence), however and the socicii-political-cultural context of any downstream decision-making process may be intensely uncertain. Such uncertainties make the process of risk communication and debate a complex and sometimes unpredictable undertaking. It is essential therefore that those elements of the risk management process that cein be objectively einalysed and evaluated (either qualitatively or quantitatively, as appropriate) are so assessed. 

Table 3 describes the main parts of an environmental risk assessment (ERA) that are based on the two major elements characterisation of exposure and characterisation of effects [27, 51]. ERA uses a combination of exposure and effects data as a basis for assessing the likelihood and severity of adverse effects (risks) and feeds this into the decision-making process for managing risks. The process of assessing risk ranges from the simple calculation of hazard ratios to complex utilisation of probabilistic methods based on models and/or measured data sets. Setting of thresholds such as EQS and quality norms (QN) [27] relies primarily on... 

It is most important that the whole life cycle of a process plant can be evaluated on safety. Safety and risk analyses evaluate the probability of a risk to appear, and the decisions of necessary preventative actions are made after results of an analysis. The aim of the risk estimation is to support the decision making on plant localization, alternative processes and plant layout. Suokas and Kakko (1993) have introduced steps of a safety and risk analysis in Figure 2. The safety and risk analysis can be done on several levels. The level on which the analysis is stopped depends on the complexity of the object for analysis and the risk potential. 

This chapter is by no means a comprehensive portrait of risk management issues. Many exceedingly complex technical and policy matters, to say nothing of the often volatile political factors, influence decision-making in particular cases. Emphasis here is on certain technical issues that arise in the use of the risk information that has been the subject of this book. 

Initially, when the number of compounds and samples is high, method quality can be balanced by the need for speed. The risk of a potentially incorrect decision based on low-quality bioanalysis is much more manageable in early discovery, particularly because this phase is not regulated but is for decision making and candidate selection purposes only. Expectations for method quality are generally lower for in vitro samples than those from in vivo studies. This is due in part to the amount of effort required to synthesize the relatively modest amount of compound for an in vitro experiment compared to the amount necessary to dose animals and also due to the complexity of the sample matrix, which is much simpler for in vitro samples than in vivo samples such as plasma or tissue. 

Another view explores the limits of the risk assessment-based approach to decision-making and what a precautionary paradigm might look like. The precautionary principle calls for preventive actions when there is reasonable scientific evidence of harm, although the nature and magnitude of that harm may not be fully understood scientifically. While a highly contentious term, proponents of the precautionary approach see this as a means to make better, more health protective decisions in the face of highly uncertain and complex risks. 

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