Donna M. Riley, Human Factors in Exposure Analysis for Consumer Paint-Stripper Use

Committee: Paul Fischbeck (SDS/EPP), Baruch Fischhoff - co-chair (SDS/EPP), Mitchell Small - co-chair (CEE/EPP), and Michael Wogalter (North Carolina State Univ.)

This dissertation develops a risk-communication assessment methodology that integrates consumer beliefs and behavior with quantitative exposure analysis.

The characterization of risks related to paint stripping requires an understanding of the time-activity and product-use patterns of consumers, as well as quantitative exposure modeling based on those estimates. A quantitative indoor air-quality model was developed for characterizing methylene chloride exposure during home paint-stripper use, with certain parameters supplied by consumers themselves. Mental models interviews were conducted with consumers in order to gather information about their understanding of the paint-stripping process and its risks, as well as detailed data on time-activity patterns for use in the quantitative model.

The integration of behavioral and physical data is used to assess the effectiveness of different precautionary behaviors, predicting the amount of exposure reduction expected from the implementation of each. The model can be used to prioritize information for label design, based on what consumers need to know as well as what they already know. The model can also be used to predict exposure for people acting on information provided to them in existing communications, after making some assumptions about how that information is likely to be understood and translated into behavior.

Assessing the potential impact of these exposure-reduction strategies highlights the promises and limitations of consumer information as an alternative to regulation.

Work supported by the Center for Emissions Control and through a Dolores Zohrab Liebmann Fellowship.

James N. Follin, Environmental Risks, Decision Making, and Public Perception: A Case Study Involving Environmental Impact Statements

Committee: Christopher Brussalis (Hill Group), Donald Connors (Westinghouse), Mike DeKay (EPP/Heinz), Paul Fischbeck - chair (SDS/EPP), and Mitchell Small (CEE/EPP)

The federal government prepares an Environmental Impact Statement (EIS) for actions which significantly affect the environment. A broad sample of over 300 EISs from 1990 to 1995 was reviewed and categorized. A survey was used to determine the public's perceptions of ecological, environmental, human health and safety, and quality-of-life impacts from EISs. The relative importance that the public places on different aspects of the EIS decision-making process was assessed using a conjoint analysis. Finally, a statistical model was developed to predict litigation likelihood and EPA's rating of EISs.

Complex EIS with many consequential impacts were the most likely to be litigated and most likely to receive a poor rating from the EPA. Geographical region, sponsoring agency, and the public's view and concerns of generic projects were not predictive of litigation likelihood or EPA rating. A high correlation was found between the level of impacts and both the likelihood of litigation and a poor EPA rating. Therefore, reduction of the level of impacts through feasible mitigation and thorough planning is warranted.

Cumulative or net impact scores do not adequately capture the underlying concerns. Models of public's perception of complex multi-attribute projects must include separate factors for positive and negative impacts associated with each dimension. Duration is a significant factor for describing environmental impacts. Public perception of a project becomes more negative the more they consider it in detail. People were generally consistent and were able to predict accurately the factors influencing the ranking of complex multi-attribute projects. No single description of the public's preference towards environmental attributes was found. Scoping is crucial to identifying all the attitudes of the public. It must include laypeople, and not just advocacy groups and experts. The public's view of "environment" includes visual, cultural, and noise as environmental impacts.

The work was supported by the Bettis Atomic Power Laboratory-Westinghouse Electric Corp., and the B.G. Lamme Foundation.

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