The crucial role played by the tolerance for risk in the causation of accidents is explained by means of an attempt to integrate the existing theories of driver behaviour in a comprehensive model. The proposed model, which attempts to be a comprehensive integration of all variables that have been demonstrated to influence road user behaviour, is a model that views the causation of accidents as a homeostatically controlled process. According to this model, a driver perceives at any moment of his trip a certain amount of risk, which he compares with the amount of risk that he is prepared to accept. To the extent that the amount of perceived risk is greater than the amount of risk tolerated, he will try to apply a greater amount of caution; just as the perceived amount of risk depends upon the perceptual skills of the driver so does the real amount of caution depend upon his ability to make the correct decisions and to execute these in an adequate manner. When these conditions are fulfilled, the probability of accidents is reduced. However, drivers become aware of the reduction in the number of accidents after some time, and, as a consequence, the amount of generally perceived risk will likewise diminish. The frequency of accidents, therefore, will increase subsequently, until the old equilibrium is re-established. A primary conclusion which follows from this view is that it is necessary to make a clear distinction between those accident countermeasures of which a temporary effect may be expected, and those countermeasures which may have a more permanent effect. The latter category of countermeasures all focus upon reduction of the level of accepted risk. Examples of such actions are given and two experiments relevant to such actions are referred to.

  • Supplemental Notes:
    • Sponsored by the Canadian Ministry of Transport, Road and Motor Vehicle Traffic Safety Office. Presented at the Dutch Road Safety League, Annual Convention, 26 April, 1975, Amsterdam.
  • Corporate Authors:

    Queen's University, Ontario

    Department of Civil Engineering
    Kingston, Ontario  Canada  K7L 3N6
  • Authors:
    • WILDE, GJS
  • Publication Date: 1975-4

Media Info

  • Features: Figures; References;
  • Pagination: 35 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00132120
  • Record Type: Publication
  • Source Agency: Highway Safety Research Institute
  • Files: TRIS
  • Created Date: Oct 29 1977 12:00AM