A Synthesis of US Glare Screen Warrants and Design Requirements with Model Warrants and Design Guide

Headlight glare can cause disruption to vision, debilitating a driver and making the driving task less safe, potentially leading to crashes. Across the United States, glare screens are used by many state transportation agencies to reduce glare caused by the headlights of traffic in opposing lanes. Design requirements and guidance are not consistent from state to state and, while there has been some national level guidance on use of glare screens, there are currently no consistent warrants for their use. The purpose of this thesis is to provide a synthesis of state transportation agency warrants and design guidance for the design and use of glare screens, and then to propose a consistent model warrant and design guide. A systematic survey of design manuals, guides, specifications, and other design related documents was conducted on a sampling of 30 state transportation agencies in the United States to determine the current warranting, design guidance, and practice regarding the use of glare screens by state transportation agencies. An evaluation was made concerning the development of warrants for glare screen use and crafting a practical design guide for engineers tasked with implementing glare screens on transportation projects. Implementation of the recommendations proposed in this thesis would result in nation-wide standardization of glare screen design criteria, give roadway designers a basis for beginning their recommendations, and potentially increase driving safety.