an Exploratory Survey of Drivers’ Knowledge of right of Way at Freeway on-ramp merging areas

This paper explores drivers' knowledge regarding The righT of way aT freeway on-ramp merging areas, including Their acTions when driving aT Those areas. a sample of 530 ohio drivers parTicipaTed in mail and online surveys ThaT assessed Their demographic characTerisTics, knowledge of righT of way, and merging pracTices. inTroducTion Motor vehicle crashes are one of the leading causes of death in the United States. 1 The most recent data available show that in 2006 there were almost 6 million police-reported motor vehicle crashes in the United States where a total of 42,642 people were killed and an additional 2.6 million were injured. 2 The majority of these motor vehicle crashes occurred at intersections or within the intersection influence areas. 2 Traffic conflicts occur at intersections due to traffic streams moving in different directions interfering with each other, and as a result they become areas with high potential for traffic crashes compared with non-intersection areas of the roadways. 3 In order to reduce the potential conflict points, access to a freeway is only provided through grade-separated intersection ramps (also known as interchanges). Freeways play a major role in providing mobility due to their high operational speeds and their being fully access controlled. Like other intersections , freeway-ramp areas have also been identified as locations highly prone to crashes as compared to other segments of freeways. 4–6 A number of studies have been conducted to determine the causes and characteristics of crashes that occur at freeway ramps in order to devise and apply preventive countermeasures to reduce the occurrences of such crashes. Most of these studies have focused on developing and calibrating factors that contribute to traffic crash occurrences such as highway geometry, traffic volume, ramp location, and type of interchange. 4,7–10 Other studies analyzed the type and patterns of crashes on urban freeways. 5,11 For instance, a study by McCartt et al 5 highlighted types and characteristics of