eration facilities. The most effective decisions are the ones that take uncertainty and variability fully into account.
When key uncertainties become very large, quantitative estimates of risk may do little to change the previously held beliefs of interested or affected parties. Those who favor the use of incineration technology tend to focus on results in the middle range, and those who are opposed to incineration tend to focus on scenarios associated with the high exposures.
Decisionmakers should coordinate with risk assessors in identifying the uncertainties and variabilities associated with estimating the health risks of waste incineration that are likely to have the greatest impact on the specific decision to be made.
Decisionmakers should consider individual and societal values regarding uncertain adverse consequences by eliciting individual or societal preferences, using decision analysis, and applying theories of science policy, social-welfare economics, and ethics.
Assessments of public-health risk posed by waste incineration should consider, through the use of sensitivity analyses or otherwise, the importance of emissions resulting from off-normal activities in addition to routine stack emissions or fugitive emissions.
Incinerator risk assessments should include the following components of uncertainty and variability analyses:
An estimate of the variability and uncertainty distributions of all input values and their effect on final estimates.
A sensitivity analysis to assess how model predictions are related to variations in input data.
Variance-propagation models that show how the variability and uncertainty of final results are tied to the uncertainties and variabilities associated with various models, their inputs, and assumptions used throughout the risk assessment.
Risk assessments should provide information that can be used to support informed debate on the various issues of concern regarding the health of community members. Assessments should include a summary of local community concerns and a description of how they have been or will be addressed in the risk-assessment process.