English, 12 pages, 7 figures, 10 references
Keywords: reaction time, distribution function

The assumed driver reaction time may have an enormous impact on the avoidance of an accident. Nevertheless it is more or less considered as a constant in German jurisdiction, at least since the “Deutscher Verkehrsgerichtstag” (German Council on Jurisdiction in Traffic) has given its recommendations in the early 80s. The paper presents experiments conducted by the author, which – as well as others – reveal a considerable variation of the reaction time of one and the same person even under controlled test conditions. The reaction time may only be described by statistical means, i.e. in terms of a distribution density function. These show a unique pattern that may also be found in the raw data leading to the German recommendations. This data has been re-interpreted by us. The paper ends with an international comparison of driver reaction experiments and the use of reaction times in jurisdiction.