1. Protocol for Cryptosporidium Risk Communication for Drinking Water Utilities Mitch Small, Baruch Fischhoff, Claire Palmgren, Felicia Wu, Elizabeth Casman Sponsored by a grant from the American Water Works Association Research Foundation CIS oƒ HDGC Carnegie Mellon Center for Integrated Study of the Human Dimensions of Global Change, Carnegie Mellon University

2. What is cryptosporidiosis? Acute gastrointestinal disease Caused in humans by an intracellular protozoan parasite, Cryptosporidium parvum Symptoms include explosive watery diarrhea, nausea, low-grade fever Self-limiting in otherwise healthy hosts Can be fatal in people with AIDS No cure currently available

3. How should utilities report this information to avoid misunderstandings? How can utilities communicate risk and uncertainty while maintaining customer confidence? How can the utility be sure customers understand the information? Small concentrations of Cryptosporidium are likely to be found in many drinking- water source and finished waters.

4. Mental Models Methodology Depicts an individual’s beliefs regarding a risk process and the options for addressing the risk Identifies crucial gaps in information and misunderstandings by contrasting the mental model with an expert model

5. Develop expert model of Cryptosporidium transmission Interview public about Cryptosporidium risk Develop lay public mental model of Cryptosporidium risk Compare lay knowledge with expert model to identify significant gaps Create structured questionnaire incorporating critical facts and gaps Create communication instrument Test success of communication Iteratively refine communication Mental Models Protocol CIS oƒ HDGC Carnegie Mellon

6. Top Level Diagram: Awareness, Communication, and Behavior Expert Model

7. Contamination of Drinking Water Module

8. Health Effects Module

9. Other Sources Module

10. Progress to date: Completion of Expert Model External Review of Expert Model Review of existing communication instruments (brochures and websites) for content, form, and accessibility Development of lay elicitation materials Pre-testing of lay elicitation protocol Completed plan for in-depth interviews CIS oƒ HDGC Carnegie Mellon