When signage on a rural highway in Kansas was upgraded, the State received some comments that begged the question of whether modern highly reflective sign sheeting materials could, in some circumstances, actually decrease the legibility of signage, particularly for older drivers. Older drivers tend to have poorer visual acuity, requiring larger signs to provide the same legibility as found in a younger population. However, older drivers also tend to be more sensitive to glare and slower to recover from glare blindness. This study was conducted to determine if highly reflective sheeting could cause a reduction in sign legibility due to veiling glare, especially in older drivers. The test was conducted using 60 drivers in an actual automobile and full scale signs and distances. The data collection was conducted in a test facility where external factors could be eliminated, isolating the variables of greatest interest. Older drivers as a whole were found to exhibit poorer performance in terms of visual acuity and response time, but no detrimental effects attributable to glare were observed. (Author/publisher)
Abstract