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E-FAST - Exposure and Fate Assessment Screening Tool - Common Questions and Answers

Q: How should I send comments to you about E-FAST? When do you expect to have your next version?

A: We are interested in your feedback from both a scientific and a computer user perspective. This version will be updated periodically. To further this process we encourage you to please send any comments to:

David A. Tobias
1200 Pennsylvania Avenue., N.W.
Washington, DC 20460

Q: The Office of Pollution Prevention and Toxics used to support several screening level, DOS-Based, exposure assessment tools. The list of tools included, SEAS, Facsearch (previously know as SIDS), PDM3, FLUSH, DERMAL, and SCIES. What happened to these tools?

A: All of these tools were updated into a Windows®-based format and integrated together to create the original E-FAST model. This means that instead of running the individual cluster of DOS-Based tools, a user now only needs to run the E-FAST model. This model upgrade and integration into a single Windows-based system is a major advance in data handling, user friendliness and efficiency.

Q: Where can I find information about how the model calculates concentration in the environment and exposures?

A: The E-FAST documentation manual is available on this web site; it is a PDF file linked from this page. This manual documents every concentration and exposure calculation in the model. Most of the documentation is also available through the model's Help system.

Q: Has the E-Fast model been peer reviewed?

A: The consumer exposure model (CEM) within E-FAST was peer reviewed in 1989, at that date it was called the consumer and occupational model (COM). Six external reviewers evaluated the models that calculate inhalation and dermal exposure doses, the input parameters chosen to set up the default scenarios for different consumer product categories, the interpretation of the outputs and the overall user friendliness of CEM. The peer review document includes a summary of the received comments and the entire response received from each peer reviewer in the document’s appendices.

The environmental and general population exposure model components of the EFAST model were reviewed in 2001 by five external reviewers. The peer review document includes a summary of the received comments. Models addressed included surface water, drinking water and fish ingestion exposures, and inhalation exposures due to stack and fugitive air emissions.

Comments from both peer reviews have been addressed and incorporated into this version of E-FAST. 

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