Industrial workspaces intended to accommodate adults, who use a wheelchair, must consider the reach capabilities of the users. This research employed a direct anthropometric measurement approach to the study of the normal reach area (NRA) and the maximum reach envelope (MRE) of a sample of 42 male and 20 female, adult wheelchair users. A computerized potentiometric system for anthropometric measures (CPSAM) was designed, built and tested for use in this study. The CPSAM recorded the position of a movable pointer in 3-D space with respect to a table reference point. The subjects were positioned in front of an adjustable worksurface and asked to produce three trials of each of their normal and maximum reach. The 3-D Cartesian coordinate values were converted to cylindrical coordinates to model the reach surfaces. Using multiple linear regression of the reach surface separate linear equations were derived to describe the 5th, 50th and 95th percentile reach boundaries for males and females, separately. The overall root mean square error of the reach equations across the males and females ranged from 4 to 17mm for the NRA and 12-39mm for the MRE.