ABSTRACT
Driving speed is one of the most important factors influencing road safety. Speed not only affects the severity of a crash but is also related to the risk of being involved in a crash. Although human factor is considered to be the most important one, road geometry is getting more concerned in safety analyses. In Poland, every year around 70% of all traffic accidents occur in urban areas, from which most is recorded at intersections as a consequence of excessive speed. This paper investigates the influence of geometry characteristics in terms of driving lane width, channelization and traffic organization on average speed under free-flow conditions. The speed measurements were undertaken in Bialystok, Poland on approaching sections of three-arm priority intersections situated in an urban area. Speed data were collected under free-flow conditions with the use of radar speed gun. To establish the statistical efficiency, the variance analyses were applied.
