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Project Dates
03/01/2011 - 09/30/2014
Principal Investigators
Project Status
Project Description

The Manual on Uniform Traffic Control Devices (MUTCD) requires that guide signs (the typical green signs along highways that contain destination and exit information) be either illuminated or retroreflective. In many locations in New York State, particularly in and around New York City (New York State Department of Transportation [NYSDOT] Region 11), overhead guide signs are illuminated by NYSDOT with external lighting systems in order to ensure sufficient visibility, even though NYSDOT also uses retroreflective materials in all of its signs. External sign lighting systems entail high installation and operating costs, require difficult maintenance especially in urban locations with high traffic densities, and can contribute to light pollution.

The tasks to be performed by the the research team at RPI under the management of the NYSDOT Project Manager. These team will assist NYSDOT in the development of specification and measurement procedures to ensure that retroreflective signs meet meaningful visual performance criteria, both upon initial installation and after periods of use in the field.

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