The Civil Engineering Division (DWW) of the Department of Public Works commissioned the SWOV Institute for Road Safety Research to carry out an accident analysis. The purpose of this analysis was to assess how the road hazard associated with porous asphalt (ZOAB) differs from that of non-porous asphalt (DAB), in particular during rain or on wet road surfaces. This study consisted of a statistical analysis of accidents registered on the main carriageways of motorways, distinguished according to driving direction and number of lanes. Only those road sections which did not contain acceleration lanes, exit ramps, bifurcations or weaving sections were considered. The study primarily considered 75 pairs of DAB and ZOAB motorway sections at 53 locations, with two lanes per carriageway. The result of the study is that the safety of ZOAB is equivalent to that of DAB. A spread in the result was shown, so that the anticipated actual difference in risk may vary between - 10 to 15% (ZOAB safer), and + 10 to 15% (DAB safer). In addition, the study did not discover a statistically significant difference between the risks associated with the DAB and ZOAB road sections during either rainy or dry conditions.
Abstract