Phase II—Study 6 was part of the Enhanced Night Visibility project, a larger research effort investigating drivers’ visual performance during nighttime driving. Study 6 evaluated the possibility of improving the detection distances of pavement markings through the use of fluorescent materials, combined with augmentation of vehicle headlamps with UV–A sources. Three different pavement marking materials and 11 headlamp configurations, — vision enhancement systems (VESs)—were evaluated. The VESs studied included halogen low beam (HLB), high intensity discharge (HID), halogen high beam (HHB), and high output halogen (HOH) sources. Both the HLB and HID configurations were used in the systems augmented with UV–A sources. The pavement marking materials included fluorescent paint, fluorescent thermoplastic, and a two-component liquid system. Thirty participants from three age groups (young, middle-aged, and older) participated in the study. The results indicated that all of the VESs provided adequate minimal visibility distances for all of the pavement markings at the 40-km/h (25-mi/h) speed driven and that the supplemental UV–A did not improve the detection distances obtained with either the HID or the HLB headlamps. The liquid system and thermoplastic pavement markings outperformed the fluorescent paint. The report discusses the results and implications for both headlamp type and the pavement marking materials. (Author/publisher)
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