This study compiled site characteristics from 338 transition zones in North Carolina. Out of these locations, speed data were compiled from 50 locations (for 37 locations, speed data were compiled in the field; for the remaining 13 locations, INRIX was used to compile the data). These 50 locations represented 9 different categories of speed limit transitions. Regression models were estimated to examine the relationship between the change in speed and site characteristics including the reduction in the speed limit. For all the speed limit transition categories, the average speeds after the transition were higher than the after-transition speed limits. Speed compliance was generally better for roads with more than 2 lanes that are in lower speed limit categories. The regression models indicated that transition zones with divided facilities and changes in land use to more developed areas could be associated with a larger reduction in speed after the transition.
