The Virginia Department of Transportation’s (VDOT) Road and Bridge Specifications require that retroreflective sheeting used on construction and maintenance activity signs be a fluorescent prismatic lens type that is retroreflective at entrance angles as great as 50° with observation angles of 0.2° and 0.5°. Because the validity of this requirement was recently questioned, this study was conducted to determine if the specification were appropriate or not. The study results indicate that VDOT’s wide entrance angle requirement is not appropriate for construction and maintenance signs and that observation angles should receive more attention than entrance angles.
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