An essential precondition for managing well at home is that the home environment and the technological devices fit one’s anthropometry. The musculoskeletal abilities of the elderly deteriorate with age, as does obviously also their ability to adapt to various heights, giving rise to a need for precisely tailored heights. The fixed-height approach to the most important task-surfaces is not appropriate for the elderly generation. The experiments showed the importance of work surface height as an example of physical fit similar to anthropometric fit (whole body, body parts) or optimal vision (visual conditions). The work surface height of a product, such as a microwave oven, seemed to be of importance when the whole arrangement, i.e. the placement of the product as well the product itself, was used as a basis of evaluation (paper III). Both the people and the products were measured by a researcher: in that sense, the role of the subjects was passive. The significance of placement height can also be considered evidence to show that no product is used in isolation. The daily use situation is important. The human-product-task-environment system approach can hence be recommended as a suitable basis for better understanding user needs in product development.
It was possible simultaneously to use a group of Finnish elderly persons as subjects in a functional simulator experiment and to obtain their static anthropometric measures. There is a need for more measures to be taken and descriptive studies to be made. Obviously, paper II gives quite a good estimate of Finnish elderly people’s main anthropometric measures and the frequency distribution of stature (male, female, and unisex).
The methods were modified and developed into EEE procedures, and methodological recommendations are presented in the end of each chapter. The stepwise procedure of EEE1 for an optimal chair seat height can be described as follows:
Measure a physical feature of each subject, in this case the anthropometric dimensions called popliteal height.
Make the necessary corrections, depending on what product is being considered, what its intended use is and where it is to be used. In this case, add approximately the height of the heel.
Determine the optimal measure for good fit. The optimal chair seat height is derived.
This measure can be compared to the corresponding interface measure of the product, in this case the seat height of a chair.
EEE1 should be done whenever relevant, because it shows the basic fit between the user and the product.
The procedure is usable both for the ergonomics of single applications and for making trade-offs for populations.