Design and classification of roads from the viewpoint of driving task analysis. Paper and shortened version presented to the OECD Symposium on Methods for determining geometric road design standards 1976, Helsingor, Denmark, 10-12 May 1976.

Together with traffic characteristics, road characteristics largely influence the effort the road user will have to make in performing his tasks. Traffic characteristics are not only linked closely to vehicle characteristics but also determined by road users relevant characteristics. In analysing traffic behaviour a need is assumed to exist for a subdivision of roads into categories based on a hierarchy of manoeuvring effort.