Research on Traffic Sign Retroreflective Sheeting Performance: A Synthesis of Practice

This synthesis summarizes previous research on various aspects of sign sheeting retroreflectivity in nine areas: basic retroreflectivity science; retroreflectivity materials, specifications, and measurement; sign performance; sign degradation, minimum retroreflectivity; field measurement of sign retroreflectivity; economic benefits; fluorescent materials; and safety. The synthesis of previous research serves as the basis for recommendations for selecting sign sheeting based on sheeting grade and roadway environment.