Within the development process of constructing and designing vehicles, comfort as an aspect of product quality occures to be more important.The recent developement of a new rating system, implements different aspects of scientific investigation in a multidisciplinary approach to build up an overall validation. The complex theoretical construct of comfort whith it's several aspects (i.e. postural comfort, seating comfort, thermal comfort) is split up into different criteria of evaluation. In a primary step investigation were made in order to define criteria for rating the aspects of posture comfort and seating comfort.For large persons possible deficits in design predominantly result out of the absolute size of the interior space. The limiting effects of qualitative seat characteristics predominantly surfaces in the sitting posture of small persons.These characteristics can be described by the indicator measures of the resultant and the functional knee hight, which permit a direct conclusion on the state of important body angles.The employment of six test persons in a laboratory experiment resulted in further understanding of the importance of the steering wheel position, especially regarding anthropometrical measures. The practise of the new developed rating system will show a further way to apply results of ergonomical research in the actual process of car interior construction.