Citation

Dissanayake S. J. Transp. Res. Forum 2004; 43(2): 25-36.

Copyright

(Copyright © 2004, Transportation Research Forum)

DOI

unavailable

PMID

unavailable

Abstract

Guidelines in the Manual on Uniform Traffic Control Devices allow jurisdictions to use different dimensions of stop signs, depending on traffic volume and the need for visibility. This study investigates the effects of driver age and dimensions of stop signs on braking distance performance at stop-controlled intersections. Data were collected at several stop-controlled intersections in non-residential areas of Hillsborough County, Florida, where three different sizes of stop signs were in use. Three driver age groups were considered: older drivers (over 65 years old), middle-age drivers (25-65 years old), and young drivers (under 25 years old). Statistical testing was used to determine whether the braking distances were different among driver age groups and also among different sizes of stop signs. Based on the observational data, it was found that older drivers had significantly longer braking distances for the largest size of the stop sign. Braking distances were also significantly different among the driver groups for the two larger sizes of the stop signs, but not for the smallest. These findings suggest that older drivers see the larger sign and apply the brakes sooner, resulting in the longer braking distances. The results from this study indicate that safety at stop-controlled intersections may be increased by replacing small stop signs with the largest size in non-residential areas with a significant older population.