This report presents the results of a study whose goal was the evaluation of various traffic control devices to determine their effectiveness for older drivers. The objectives of this study were threefold: (Task 1) to field test existing improvements or those currently being implemented throughout the state; (Task 2) to evaluate the effectiveness of two types of enhanced traffic control devices (a new font and new pavement marking materials); and (Task 3) to assess the feasibility of evaluating traffic control devices using simulation. The results of this study showed very definite advantages in the use of larger lettering on signage, as well as the use of wider pavement markings (stripes) and raised pavement markers. Offset left turn lanes did not show any definite advantage over conventional left turn lanes under the conditions tested. Clearview font was found to yield significantly greater legibility distances than the other fonts for advance street name signs but not for ground-mounted street name signs. As for the new lane markers evaluated, no significant differences were found in their absolute or comparative visibility. This was likely attributable to the newness of materials whose luminance contrast exceeds by far the minimum requirements for reflectivity of these materials. A more stringent evaluation would require testing these stripes at regular interval to determine if and when older drivers distinguish a difference among them before the end of their service life. These results clearly support the aim of the Elder Roadway Improvement Program in its approach to implement and evaluate traffic control devices that are geared toward enhancing a safe environment for the older driver. (Author/publisher)
Abstract