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Programs of the Office of the Science Advisor (OSA)

Probabilistic Risk Assessment to Inform Decision Making: Frequently Asked Questions

The document presents general concepts and principles of probabilistic risk assessment (PRA), describe how PRA can improve the bases of Agency decisions and provide illustrations of how PRA has been used in risk estimation and in describing the uncertainty in decision making. This document is a companion to the more detailed white paper, which also includes a compendium of 16 relevant case studies ranging in their level of complexity. Both documents describe the potential and actual uses of probabilistic tools in the risk decision process and facilitate their implementation in human, ecological and environmental risk analysis and related decision‐making at EPA.
The documents do not prescribe a specific approach to risk assessment; rather, they describe the various stages and aspects of an assessment or decision process in which probabilistic tools may add value. These are not regulatory guidance documents, but they are designed to be helpful handbooks and/or references for risk assessors, risk managers and decision‐makers interested in improving the risk assessment and decision‐making process.
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