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This legacy version of CHAD (which is in Microsoft Access format) contains detailed human activity data from 12 early studies (performed 1982-1998) and provides a desktop user interface for exploring the data. CHAD-2000 has tables of additional original data collected in these 12 studies that are not available in the current, continuously updated version of CHAD. As these data may be of interest to some researchers, EPA has made this legacy version available for download.

Download CHAD-2000(35 MB)

Download CHAD-2000 Manual
The CHAD-2000 manual describes its development and contents.

CHAD User Information:

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