THE PRACTICE OF ROAD SAFETY ENGINEERING - A CASE STUDY

Careless driving, risk taking, misjudgement or inattention are a major factor in up to 95% of all road traffic accidents. However experience indicates that in many cases road safety engineering can reduce the numbers of these accidents. The paper uses a hypothetical example to describe events leading up to a road traffic accident. In the case selected all first hand evidence (the driver's recollection of the event, a witness's statement and the opinion of the police officer attending the scene) indicates that the accident is the result of bad driving, misjudgement and inattention. However, subsequent routine monitoring of the accidents occurring on the road network reveals that the subject accident is one of a group of similar accidents. This leads to an analysis of the details of these accidents that is followed by an on site investigation. During the course of site investigation the engineer finds several factors that are likely to have relevance in the accidents. By using elementary road safety engineering techniques the engineer is frequently able to introduce a package of low cost measures that are directly related to the accident history of the site. The accident scenario is then reapplied to the changed circumstance of the implemented scheme; this demonstrates that the improvements provide the same driver with improved forward visibility, clear warnings of the approaching danger area and a higher specification of road surface. This transforms the situation and there is now a very high probability that the 'harassed driver' will be able to cope with the circumstances and the accident that is attributed to 'bad driving' is avoided. (A) For the covering abstract of the conference see IRRD E201756.