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Uncertainty Factor
Search by Uncertainty or Modifying Factor
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The search by Uncertainty or modifying factor allows you to search for composite uncertainty factor values, individual uncertainty factor values, and modifying factor values used to derive RfDs and RfCs. The search will retrieve a list of substances with uncertainty or modifying factors that fall within the specified range.
* Uncertainty factors other than the five standard uncertainty factors listed in the IRIS glossary are not routinely applied in IRIS assessments. Results of a search on other uncertainty factors will reflect only those exceptional circumstances where it was determined that the uncertainty associated with an RfD or RfC could not be adequately categorized by one of the standard UFs.
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