A ‘workspace envelope’ is a 3-dimensional space within which you carry out physical work activities when you are at a fixed location. The limits of the envelope are determined by your functional arm reach which, in turn, is influenced by the direction of reach and the nature of the task being performed. Most of the things that you need to use to carry out your tasks should be arranged within this area. Workspace envelopes should be designed for the 5th percentile of the user population, which means that 95% of users will be able to reach everything placed within the envelope.
The Growth Table, by L.A.-based architects Tim Durfee and Iris Anna Regn takes into account different age children for each space in order to provide the optimum workspace area.