You are here:
COMMUNICATING PROBABILISTIC RISK OUTCOMES TO RISK MANAGERS
Citation:
Fairbrother, A. COMMUNICATING PROBABILISTIC RISK OUTCOMES TO RISK MANAGERS. Presented at SETAC Europe Meeting, Hamburg, Germany, April 27-May 1, 2003.
Description:
Increasingly, risk assessors are moving away from simple deterministic assessments to probabilistic approaches that explicitly incorporate ecological variability, measurement imprecision, and lack of knowledge (collectively termed "uncertainty"). While the new methods provide an explicit acknowledgement of the complexity of ecological systems and the well-known axiom that the future is inherently unpredictable, they create a dilemma for the risk manager. Whereas traditional deterministic approaches provide a "bright line" outcome (either there is risk or there is no risk), the newer methods state results in terms of probability of the occurrence of an unwanted outcome. Whether or not a particular level of probability is acceptable then becomes a risk management decision, rather than being buried in the assessment through the use of assessment factors or conservative assumptions. Because of this, the degree of risk aversion of the risk manager (and his/her institution) becomes apparent. Furthermore, presentation of results from probabilistic risk assessments in an easily understood format can be challenging, particularly if there are multiple levels of uncertainty. Risk assessors using these methods need to devote additional time to development of appropriate risk communication methods, and must invest in a priori education of risk managers in what is being communicated. Risk managers must be willing to accept the responsibility of learning what the results of probabilistic assessments mean, and of subsequently making decisions on acceptability of risk that are more transparent and more subject to challenge from those who hold a different level of risk tolerance and avoidance than occurs with the current deterministic model.