An Applied Assessment of the Procedures and Criteria for Black Spot Determination

Abstract

Traffic accidents are the number one worldwide cause of death among youths and one of the major causes of death for all ages. Black spots are high risk locations where road accidents have been concentrated. Herein, a literature review of black spots determination methods is conducted. Certain broad approaches are used to identify them: crash numbers, crash rates related to exposure and gravity of accidents and quantitative methods. Generally, the threshold value of a safety indicator is first determined and in a subsequent phase, it is investigated whether the value of this indicator along a road subsection significantly exceeds that predetermined value. The various approaches adopted by some key countries are also presented. Turkey is one of them and as a country presents similarities with the relevant Greek road safety reality. Then, a comparison is made between the broad approaches and the method which is being used in Turkey along a section of the national road Athens-Thessaloniki. It is concluded that to obtain balanced results, road black spots should be determined as a coupling of both a statistical method at a relevant low confidence interval (90%) together with an accident severity index method.