Abstract
The objective of this paper is to report the results of an experiment that evaluated the effects of partial interchange lighting complete interchange lighting, and no lighting on traffic operations at a freeway interchange. A freeway interchange that possessed a modern and complete lighting system was chosen for the experiment. The lighting was temporarily modified so that two levels of partial lighting and unlit conditions could be provided. The results indicated that complete interchange lighting is superior to partial interchange lighting in providing smoother and safer nighttime operations at the interchange.