U.S. Environmental Protection Agency decision documents and communications to the public should include a discussion of which uncertainties are and are not reducible in the near term. The implications of each to policy making should be provided in other communication documents when it might be useful for readers.
Given that decision makers vary in their technical backgrounds and experience with highly mathematical depictions of uncertainty, a variety of communication tools should be developed. The public increasingly wants, and deserves, the opportunity to understand the decisions of appointed officials in order to manage their own risk and to hold decision makers accountable. With respect to which uncertainties or aspects of uncertainties to communicate, attention should be paid to the relevance to the audience of the uncertainties, so that the uncertainty information is meaningful to the decision-making process and the audience(s). Those efforts should include different types of decisions and should include communication of uncertainty to decision makers and to stakeholders and other interested parties.
The U.S. Environmental Protection Agency (EPA), alone or in collaboration with other relevant agencies, should fund or conduct research on communication of uncertainties for different types of decisions and to different audiences, develop a compilation of best practices, and systematically evaluate its communications.
As part of an initiative evaluating uncertainties in public sentiment and communication, U.S. Environmental Protection Agency senior managers should assess agency expertise in the social and behavioral sciences (for example, communication, decision analysis, and economics) and ensure it is adequate to implement the recommendations in this report.
In summary, the committee was impressed by the technical advances in uncertainty analysis used by EPA scientists in support of EPA’s human health risk assessments, which form the foundation of all EPA decisions. The committee believes that EPA can lead the development of uncertainty analyses in economic and technological assessment that are used for regulatory purposes as well as the development of ways to characterize and