The objective of this project was to monitor the performance of the diamond grade sheeting when used on both typical traffic signs and construction signs. The durability, appearance, and reflectivity of the signs were monitored. Diamond grade sheetings used on typical traffic signs were evaluated over a two-year period with construction signs evaluated over an 18-month period.

Diamond grade sheeting was found to provide increased reflectivity compared to high intensity sheeting with no problems noted related to durability or appearance. However, the cost of the diamond grade sheeting would limit its use to situations where brighter, wider-angle reflective sheeting is warranted and the increased cost can be justified. Locations where the use of diamond grade sheeting should be considered because of its higher reftectivity include the following:

  1. signs in areas with high levels of ambient lighting,
  2. work zones (especially in urban locations) where the roadway environment is visually cluttered, and
  3. high accident locations involving a nighttime accident problem.

A location where use of diamond grade sheeting could be considered because of the increased viewing angle would be for overhead signs in urban areas. These increased angles would only be a factor when the driver is attempting to view the sign at a locations close to the sign which could be the situation at urban intersections.

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The contents of this report reflect the views of the author who is responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, nor the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and trade names are for identification purposes and are not to considered as endorsements.