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Consolidated Human Activity Database (CHAD) - Documentation for CHAD-Master

EPA maintains the Consolidated Human Activity Database (CHAD). CHAD contains data obtained from pre-existing human activity studies that were collected at city, state, and national levels. CHAD is intended to be an input file for exposure/intake dose modeling and/or statistical analysis. The documents below describe CHAD and its use.

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CHAD Documentation and User’s Guide (PDF)(194 pp, 4 MB, October 2019, EPA-452/B-19-001)
Technical Memo, CHAD-APEX Updates - June 2019 (PDF)(15 pp, 905 K)
Further updates to CHAD