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CHAD-Master is continuously maintained by EPA and is updated as new human activity data become available. CHAD-Master contains human activity data from 22 different studies performed 1982-2010. It is available for download in comma separated value (CSV) and SAS dataset formats.

Download CHAD-Master (CSV)(18 MB)

Download CHAD-Master (SAS)(22 MB)

Download CHAD-Master Memo

This technical memo describes the contents of CHAD-Master.

CHAD User Information:

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