Impact assessment of revised retroreflectivity requirements for the state of Montana

Traffic signing is a critical component of the roadway, as it is the communication medium by which motorists receive information relative to warnings, regulations, and guidance. Nighttime legibility is very important to the effectiveness of roadway signs. Although external sign illumination is effective, the use of retroreflective sheeting is the most common and cost effective means of making signs visible to the driver at night. This report focuses on the collection and analysis of a sample of traffic signs, delineated according to Montana Department of Transportation (MDT) District and sign type, on the State highway system. These samples were collected on the Montana highway system, focusing on non-Interstate, non-urban areas. These data allow cost estimates to be made for suggested sign replacements by sign category, as well as indicate appropriate and feasible replacement strategies and priorities within each MDT District and the State as a whole. Recommendations are made relative to sign management systems to easily and effectively target and document signs for future maintenance. This report details work activities associated with each of the study tasks, and concludes with findings and recommendations for Montana's course of action regarding the inventory of highway signs.