ABSTRACT
Ranking risks to health, safety, and the environment is important because, while there are risks everywhere, we have limited resources for managing them. In an ideal world, we would regularly review our priorities, deciding which risks deserve more attention and which less. In the real world, systematic reviews of risk priorities are as rare in the public arena as they are in our private lives. That is, we usually muddle through, waiting until circumstances bring a risk to our attention, then decide whether to treat it more or less seriously. In our private lives, we bear the consequences, if we spend our time, money, attention, or emotional resources poorly. However, the public as a whole suffers when policy makers worry about the wrong things. When setting their priorities, policy makers face the same challenges as do individuals, one challenge being the sheer number of risks that might be considered. A second is deciding how to define “risk.” A third is reconciling the variety of values of the different stakeholders in comparing risks. The first section considers these challenges from a theoretical perspective. It is followed by a short history of US Environmental Protection Agency
(EPA) efforts to grapple with them. The next section describes an approach that combines risk research with practical experience in risk ranking followed by consideration of the compatibility of this approach with risk-management processes initiated by the Government of the United Kingdom and advocated by the Canadian Standards Association. Before beginning, it is important to note that ranking risks is but one critical step in effective risk management. Ordering risks by their importance allows policy makers to focus on those that matter most. It does not, however, say what to do about them. It does not even determine which risks require action or who should take it. There may be small risks that are easily managed and large risks that merit no further attention, because there is nothing to be done about them, beyond investing in research that might, one day, make action possible.
