The objective of the investigation was to evaluate the useful life of pavement markings. The Manual on Uniform Traffic Control Devices (MUTCD) provides general guidelines for the application and installation of pavement markings. However, performance requirements for various types of pavement markings are not included. Retroreflectivity data were collected throughout Kentucky on various longitudinal pavement markings using mobile and manual techniques. Data were collected on two-year old and one-year old lines. The retroreflectivity levels were analyzed and the several recommendations were made. Minimum levels of retroreflectivity should be set for determining what roads to restripe annually. These values should be lower than the passing/bonus thresholds used in the Quality Control/Quality Assurance (QA/QC) program. It is recommended that yellow lines should be above 100 mcd/m2/lux and white lines should be above 150 mcd/m2/lux. Retroreflectivity measurements should be collected and used to determine which roads should be painted each year. The current Maintenance Rating Program (MRP) can be used to facilitate this process. An inventory of striped roads should be maintained to allow a determination of when specific roadway sections were last restriped. The effect of the amount of beads per gallon on retroreflectivity should be studied further; however it seems fewer beads could be used
