Three evaluations of task-surface heights in elderly people's homes.

The aim of the study was to compare subjective evaluations of the heights of some kitchen facilities and furniture with an expert's opinion of the same heights and with the height recommendations derived from the subjects' anthropometric data. Experiments were conducted in a mock-up simulator, where the subjects, a group of the Finnish elderly (N = 55), performed small tasks similar to the typical daily living activities at home. The mock-up room consisted of "task-surfaces" whose heights were adjustable to various fixed positions. For example, three identical chairs with different heights were available. In their subjective assessments, the elderly systematically rated the 450 mm-high chair as the most suitable. The lowest (350 mm) and the highest (550 mm) chairs were not liked. The other two evaluations supported this conclusion. The height of the lowest kitchen shelf should not be lower than 300 cm. A work surface height of 850 mm seems preferable for most of the Finnish elderly. The different evaluation procedures gave relatively consistent results, but some important differences were also noticed and are discussed.