The aim of ergonomic design is to satisfy as large a proportion of the population as possible. This is usually not achieved by using the mean values of the appropriate anthropometric dimensions. Ideally, adjustability should be provided to cater for the wide variability of certain critical dimensions among the population. The adjustment ranges must then be carefully chosen. Even if a dimension of a chair is not made adjustable, careful choice of the best percentile on which to base the fixed dimension can minimise discomfort among the population using the chair. To illustrate the problems.
