The status of the nationally coordinated program for retroreflectivity research is described. This program was developed under the guidance of the fhwa office of safety and traffic operations researchand development. The goals of the program are to determine the end of life for retroreflective signs and markings and to develop the necessary measurement and management tools. Included are discussions of the human factors research to determine the end of life of retroreflective materials, an economic analysis of the impact of potential minimum requirements, mathematical modeling of the deterioration of sign materials, the development of computer software to manage sign inventories, and the design of new instruments to measure the retroreflectivity of signs and markings from a moving vehicle during daylight. This paper appears in transportation research record no. 1316, Visibility for roadways, airways, and seaways 1991: proceedings of aconference, july 25-26, 1990, washington, d.C.
Samenvatting