Evaluation of Guardrail Embedded Lighting System in Trinidad, Colorado

This report provides information on the design considerations of the embedded highway lighting design on Interstate-25 in Trinidad, Colorado, in terms of visibility. The information is based on visibility characterizations of small targets using luminance, illuminance, and contrast calculations as well as participant input on the detectability of small targets. Experimental conditions included two different aim angles of the lighting design (forward and cross) as well as two small target colors (red and blue). When compared to the small target detection distances produced by conventional overhead lighting systems in previous studies, the research determined that the small target visibility distances of the embedded lighting design to be shorter by approximately 50%. Adjustments to the spacing, aim, and breadth of the lighting design are recommended for future research considerations. Implementation The results of this research indicate the lighting design is an alternative; however, additional considerations to the beam angle, beam width, beam height, and spacing may improve the implementation of the system.